JP4581646B2 - Light emitting diode lighting device - Google Patents

Description

  The present invention relates to a light emitting diode lighting device that lights a plurality of light emitting diodes connected in series.

  In recent years, light emitting diode lighting devices using light emitting diodes for illumination have been widely used. In this light emitting diode lighting device, in the case of a light emitting diode having a driving voltage (rated voltage) of 3.6V, when 35 light emitting diodes are connected in series, the driving voltage becomes 126V. The pulsating voltage output from the circuit 201 is supplied to a light emitting diode circuit 203 configured by connecting 35 light emitting diodes 202 in series via a current limiting resistor 204. In the light-emitting diode lighting device configured as described above, the light-emitting diode circuit 203 can be turned on with a simple circuit configuration. However, as shown in FIG. The light is turned on only in a narrow and narrow phase range (time t1-t2 section) at the center, resulting in low power utilization efficiency with many pauses.

  Therefore, as shown in FIG. 12, the pulsating voltage output from the rectifier circuit 201 is smoothed by the electrolytic capacitor 205 to be converted into a DC voltage with little ripple, and this DC voltage is supplied to the light emitting diode circuit 203. Something like this has also been proposed. In the light emitting diode lighting device configured as described above, a constant current can always flow through the light emitting diode circuit 203, and there can be no idle period (for example, Patent Document 1).

  However, in such a light emitting diode lighting device, an electrolytic capacitor 205 having a large capacitance is required, and the inrush current when the power is turned on increases. Therefore, there is a large inrush current limiting resistor for suppressing the inrush current. In addition, since the electrolytic capacitor 205 is a life component, it is necessary to prevent the ambient temperature from becoming high, resulting in inconvenience that the lighting fixture design becomes complicated.

For this reason, as shown in FIG. 13, it is conceivable to supply the light-emitting diode circuit 207 with a DC voltage output from a switching power supply using an insulating transformer 206 set so that the secondary output is 24V. In the light-emitting diode lighting device configured as described above, an electrolytic capacitor having a large capacitance is not necessary, and a current can be constantly passed through the light-emitting diode circuit 207 so that there is no idle period.
JP 2002-158376 A

  However, in the light emitting diode lighting device using the switching power supply as described above, since the switching power supply is switched at a high frequency of several tens of kHz or more, the noise prevention circuit 208 is required before the rectifier circuit 201. Another disadvantage is that the number of points is inevitably increased, the circuit becomes larger, and the cost increases.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a light emitting diode lighting device capable of efficiently controlling lighting of a plurality of light emitting diodes connected in series with a simple circuit configuration.

  In order to achieve the above object, the invention of claim 1 is a light emitting diode lighting device for lighting a plurality of light emitting diodes connected in series, wherein a pulsating voltage obtained by rectifying an alternating voltage is used as the plurality of light emitting diodes. In the phase range in which the pulsating voltage supplied from the rectifier circuit changes from a low value to a high value, the light emitting diode is adjusted so that the number of lighting increases corresponding to the change. And a lighting control circuit for controlling the lighting of the light emitting diodes so that the number of lighting is reduced corresponding to the change in a phase range where the pulsating voltage changes from a high value to a low value. It is said.

  According to a second aspect of the present invention, in the first aspect, the lighting control circuit is connected between a predetermined connection point and a ground among a plurality of connection points between adjacent light emitting diodes of the plurality of light emitting diodes. In the phase range in which the pulsating voltage changes from a low value to a high value, and corresponding to the change, a plurality of the driving switch elements and a light emitting diode on the ground side from a light emitting diode on the high potential side among the plurality of light emitting diodes In a phase range in which the pulsating current voltage changes from a high value to a low value, the predetermined driving switch element is turned on so that the number of lighting increases toward the Among the plurality of light emitting diodes, the plurality of driving switch elements are arranged so that the number of lightings decreases from the ground side light emitting diode toward the high potential side light emitting diode. It is characterized in that a switch control circuit for turning on the predetermined driving switch element within the.

  According to a third aspect of the present invention, the switch control circuit according to the second aspect includes a microcomputer including a clock oscillation circuit, wherein the number of clocks generated by the clock oscillation circuit and the The instantaneous value of the pulsating voltage is associated with the zero potential point of the pulsating voltage as a reference, and when the number of clocks is in a phase range where the pulsating voltage changes from a low value to a high value, the number of clocks Corresponding to, turning on a predetermined drive switch element among the plurality of drive switch elements so that the number of lighting increases from the light emitting diode on the high potential side to the light emitting diode on the ground side among the plurality of light emitting diodes, When the number of clocks is in a phase range in which the pulsating voltage changes from a high value to a low value, the plurality of light emitting diodes correspond to the number of clocks. It is characterized in that to turn on the predetermined driving switch element of the plurality of drive switching element so that the lighting number is decreased toward the Chi ground side of the light emitting diode to the high potential side of the light emitting diode.

A fourth aspect of the present invention, in which according to claim 2, wherein the switch control circuit, the corresponding one of the plurality of drive switches by the instantaneous value of the pulsating voltage is in the driving state exceeds a predetermined value An element drive control circuit configured by connecting a plurality of element drive circuits for turning on the drive switch to each other in parallel with the rectifier circuit, and a drive switch connected between a connection point between the light emitting diodes and the ground When a cutoff switch element that is driven and controlled by the element drive control circuit is connected between each control terminal of the element and the ground, and when a predetermined drive switch element is turned on among the plurality of drive switch elements And an element cut-off circuit for turning off the drive switch element that is turned on at a higher potential side than the drive switch element, and the pulsating voltage is low. In the phase range in which the value changes from a high value to a high value, the plurality of drivings are performed so that the number of lighting is increased from the light emitting diode on the high potential side toward the light emitting diode on the ground side among the plurality of light emitting diodes. In a phase range in which a predetermined drive switch element is turned on among the switch elements and the pulsating voltage changes from a high value to a low value, a high potential is applied from the light emitting diode on the ground side among the plurality of light emitting diodes in response to the change A predetermined drive switch element is turned on among the plurality of drive switch elements so that the number of lighting is reduced toward the light emitting diode on the side.

  The invention of claim 5 is a light emitting diode lighting device for lighting a plurality of light emitting diodes connected in series, and supplies a pulsating voltage obtained by rectifying an AC voltage to a series connection circuit of the plurality of light emitting diodes. A rectifier circuit and a plurality of light emitting diodes connected in series are connected in series, and the impedance value is varied corresponding to the instantaneous value of the pulsating voltage, and the pulsating voltage changes from a low value to a high value. In the phase range in which the impedance value is sequentially increased in response to the change, and in the phase range in which the pulsating voltage is changed from a high value to a low value, the impedance value is sequentially reduced in response to the change. It is characterized by

  According to a sixth aspect of the present invention, the variable impedance circuit includes a plurality of resistance elements connected in series, the resistance circuit connected in series to the plurality of light emitting diodes, and the resistance circuit. A plurality of short-circuit switch elements that are connected to both ends of the resistance element and short-circuit the resistance element, and in a phase range in which the pulsating voltage changes from a low value to a high value, the resistance value of the resistance circuit corresponds to the change. The impedance value is sequentially increased by turning the short-circuit switch element from on to off so as to increase, and in the phase range where the pulsating voltage changes from a high value to a low value, the resistance of the resistance circuit corresponds to the change. And a switch control circuit for sequentially decreasing the impedance value by turning the short-circuit switch element from OFF to ON so that the value decreases. .

  The invention according to claim 7 is the invention according to claim 6, wherein the switch control circuit includes a microcomputer including a clock oscillation circuit, and the number of clocks generated by the clock oscillation circuit The instantaneous value of the pulsating voltage is associated with the zero potential point of the pulsating voltage as a reference, and when the number of clocks is in a phase range in which the pulsating voltage changes from a low value to a high value, The impedance value is sequentially increased by turning the short-circuit switch element from on to off so that the resistance value of the resistance circuit increases in response to the number of clocks, and the number of clocks changes from a high value to a low value of the pulsating voltage. In this phase range, the impedance value is gradually decreased by turning the short-circuit switch element from OFF to ON so that the resistance value of the resistor circuit decreases corresponding to the change. It is characterized in that it is shall.

  The invention according to claim 8 is the one according to claim 5, wherein the variable impedance circuit comprises a plurality of resistance elements connected in series, and a resistance circuit connected in series to the plurality of light emitting diodes; A plurality of drive switch elements connected between respective connection points of adjacent resistance elements of the resistance element and the ground, and a phase range in which the pulsating voltage changes from a low value to a high value, corresponds to the change. A phase in which the impedance value is sequentially increased by turning on a predetermined drive switch among the plurality of drive switch elements so that the resistance value of the resistance circuit increases, and the pulsating voltage changes from a high value to a low value. In the range, the impedance is changed by turning on a predetermined drive switch among the plurality of drive switch elements so that the resistance value of the resistor circuit decreases in response to the change. It is characterized in that a switch control circuit for sequentially reduced dance values.

A ninth aspect of the invention relates to the eighth aspect of the invention, wherein the switch control circuit corresponds to the driving switch when the instantaneous value of the pulsating current voltage exceeds a predetermined value. An element drive control circuit configured by connecting a plurality of element drive circuits for turning on the drive switch to each other in parallel with the rectifier circuit; and a drive switch connected between a connection point of the resistance elements and a ground A cut-off switch element that is driven and controlled by the element drive control circuit is connected between each control terminal of the element and the ground, and when the predetermined drive switch element is turned on among the plurality of drive switch elements, the drive is performed The drive switch element that is turned on on the higher potential side than the switch element includes an element cutoff circuit that turns off when the cutoff switch element is turned on. Therefore, in the phase range in which the pulsating voltage changes from a low value to a high value, corresponding to the change, the resistance element of the resistance element from the high potential side resistance element to the ground side resistance element among the plurality of resistance elements. In a phase range in which the impedance value is sequentially increased by turning on a predetermined drive switch element among the plurality of drive switch elements so that the number of connections is increased, and the pulsating voltage is changed from a high value to a low value. Corresponding to the change, a predetermined number of the drive switch elements are selected from the plurality of resistance elements so that the number of connections of the resistance elements is decreased from the resistance element on the ground side toward the resistance element on the high potential side. It is characterized in that the impedance value is sequentially reduced by turning on the drive switch element.

  According to the first aspect of the present invention, the number of light emitting diodes to be lit is increased / decreased corresponding to the instantaneous value of the pulsating voltage, and therefore, it is possible to efficiently control lighting of a plurality of light emitting diodes connected in series with a simple circuit configuration. .

  According to the invention of claim 2, the predetermined drive switch connected between the predetermined connection point and the ground among the plurality of connection points of the adjacent light emitting diodes is turned on corresponding to the instantaneous value of the pulsating voltage. Thus, the number of light-emitting diodes to be lit is increased / decreased, so that a plurality of light-emitting diodes connected in series can be efficiently controlled with a simple circuit configuration.

  According to the invention of claim 3, the predetermined drive switch connected between the predetermined connection point and the ground among the plurality of connection points of the adjacent light emitting diodes corresponds to the number of clocks generated by the clock oscillation circuit. Since the number of lighting of the light emitting diodes is increased or decreased by turning it on, lighting control of a plurality of light emitting diodes connected in series can be efficiently performed with a simple circuit configuration.

  According to the invention of claim 4, the predetermined drive switch connected between the predetermined connection point and the ground among the plurality of connection points of the adjacent light emitting diodes is driven corresponding to the instantaneous value of the pulsating voltage. Since the number of light-emitting diodes to be turned on / off is increased / decreased by turning on the element drive control circuit and the element cut-off circuit, it is possible to efficiently control lighting of a plurality of light-emitting diodes connected in series with a simple circuit configuration.

  According to the invention of claim 5, since the impedance value of the variable impedance circuit connected in series to the light emitting diode is increased or decreased according to the instantaneous value of the pulsating voltage, a plurality of light emitting diodes connected in series can be configured with a simple circuit configuration. Lighting control can be performed efficiently.

  According to the sixth aspect of the present invention, the short-circuit switch element connected to both ends of the plurality of resistance elements connected in series is controlled to be turned on / off corresponding to the instantaneous value of the pulsating voltage, thereby being variable connected in series to the light emitting diode. Since the impedance value of the impedance circuit is increased or decreased, it is possible to efficiently control lighting of a plurality of light emitting diodes connected in series with a simple circuit configuration.

  According to the seventh aspect of the present invention, the short-circuit switch element connected to both ends of the plurality of resistance elements connected in series is connected in series to the light emitting diode by on / off control corresponding to the number of clocks generated by the clock oscillation circuit. Since the impedance value of the variable impedance circuit is increased or decreased, it is possible to efficiently control lighting of a plurality of light emitting diodes connected in series with a simple circuit configuration.

  According to the invention of claim 8, the predetermined drive switch connected between each connection point of the adjacent resistance elements of the plurality of resistance elements connected in series and the ground corresponds to the instantaneous value of the pulsating voltage. Since the impedance value of the variable impedance circuit connected in series to the light emitting diode is increased or decreased by turning on the light, it is possible to efficiently control lighting of the plurality of light emitting diodes connected in series with a simple circuit configuration.

  According to the ninth aspect of the present invention, the predetermined drive switch connected between each connection point of the adjacent resistance elements of the plurality of resistance elements connected in series and the ground corresponds to the instantaneous value of the pulsating voltage. Since the impedance value of the variable impedance circuit connected in series to the light emitting diode is increased or decreased by turning on the element drive control circuit and the element cut-off circuit that are driven in a simple manner, a plurality of light emitting diodes connected in series can be configured with a simple circuit configuration. Lighting control can be performed efficiently.

  FIG. 1 is a diagram showing a circuit configuration of a light-emitting diode lighting device according to the first embodiment of the present invention. In this figure, a light emitting diode lighting device 10a is supplied with a rectifier circuit 13 connected to a sine wave AC power source (50 Hz or 60 Hz) 11 having an effective value of 100 V via a fuse 12, and an output voltage from the rectifier circuit 13. A light-emitting diode circuit 15 configured by connecting a plurality of light-emitting diodes 14 in series in the same direction, and a current-limiting resistor element (current-limiting resistor) connected between the rectifier circuit 13 and the light-emitting diode circuit 15. Element) 16 and a lighting control circuit 17 that controls the lighting of each light-emitting diode 14 of the light-emitting diode circuit 15.

  The rectifier circuit 13 is configured to obtain a pulsating voltage having an output waveform as shown in FIG. 2 by performing full-wave rectification by a plurality of rectifier elements (not shown). The light-emitting diode circuit 15 is formed by connecting a plurality of light-emitting diodes 14 in series with each anode directed toward the high potential side of the rectifier circuit 13 and each cathode directed toward the ground side. The predetermined number of light emitting diodes 14 are divided into a plurality of groups.

  That is, in this embodiment, the light-emitting diode circuit 15 is configured by a total of 35 light-emitting diodes 14, each of which includes a first diode circuit 17, a second diode circuit 18, and a third diode composed of six light-emitting diodes 14. Diode circuit 19, fourth diode circuit 20, fifth diode circuit 21, and sixth diode circuit 22 including five light-emitting diodes 14. The lighting control is performed in units of groups corresponding to the instantaneous value of the pulsating voltage supplied from.

  Further, the light emitting diode circuit 15 includes a first intermediate resistance element 23 between the first diode circuit 17 and the second diode circuit 18, and the second diode circuit 18 and the third diode circuit 19. A second intermediate resistance element 24 is connected between the third diode circuit 19 and the fourth diode circuit 20, and a third intermediate resistance element 25 is connected between the fourth diode circuit 20 and the fourth diode circuit 20. The fourth intermediate resistance element 26 is connected between the fifth diode circuit 21 and the fifth intermediate resistance element 27 is connected between the fifth diode circuit 21 and the sixth diode circuit 22. Yes. The first to fifth intermediate resistance elements 23 to 27 constitute a current limiting resistance element together with the current limiting resistance element 16.

  The lighting control circuit 17 includes a first drive switch element 30 with a control terminal made of a MOSFET connected between the connection point of the first diode circuit 17 and the first intermediate resistance element 23 and the ground, A second drive switch element 31 with a control terminal made of a MOSFET connected between the connection point of the diode circuit 18 and the second intermediate resistance element 24 and the ground, the third diode circuit 19 and the third diode circuit 19 A third drive switch element 32 having a control terminal made of a MOSFET connected between a connection point of the intermediate resistance element 25 and the ground, and a connection point of the fourth diode circuit 20 and the fourth intermediate resistance element 26 A fourth drive switch element 33 having a control terminal made of a MOSFET connected to the ground, a fifth diode circuit 21 and a fifth intermediate resistance element The fifth drive switch element 34 having a control terminal made of a MOSFET connected between the connection point 7 and the ground, and the light emitting diode 14 at the final stage on the ground side of the sixth diode circuit 22 and the ground. And a sixth drive switch element 35 with a control terminal made of a MOSFET connected to.

  The lighting control circuit 17 supplies the control signal to the control terminals (the gates of the MOSFETs) of the first to sixth drive switch elements 30 to 35 via the current limiting resistor elements 36 to 41, thereby providing the first. A pulsating current output from the rectifier circuit 13 includes a switch control unit 45 configured by a microcomputer that controls on / off of the sixth driving switch elements 30 to 35, and a series connection circuit of a resistance element 46 and a capacitor 47. A voltage supply circuit 48 that rectifies the voltage to a DC voltage of a predetermined value (for example, 5 V) and supplies the voltage to the switch control unit 45, and a series connection circuit of a plurality of resistance elements 49 and 50 connected to the rectification circuit 13. And a voltage detection circuit 51 for detecting an instantaneous value (voltage value) of the pulsating voltage output from the rectifier circuit 13. The switch control unit 45, the voltage supply circuit 48, and the voltage detection circuit 51 constitute a switch control circuit 52.

  Here, the switch control unit 45 includes a clock oscillation circuit 53 that generates a clock signal for operating the switch control unit 45, and a reset circuit that resets the operation of the switch control unit 45 when the power is input or when the power is shut off. 54 and a counter 55 that counts the number of clocks generated by the clock oscillation circuit 53, and a time discriminating unit that discriminates whether or not the time counted by the counter 55 has reached a predetermined value. The voltage detection circuit 51 detects the switching element control unit that controls on / off of the first to sixth drive switch elements 30 to 35 by supplying a control signal to the control terminal corresponding to the time (time). The instantaneous value of the pulsating voltage is based on the comparison result with the reference value in the comparison circuit provided in the interface circuit (not shown). And a respective function realizing unit as a voltage determination unit for determining whether it is zero potential can.

  That is, the switch control unit 45 stores the number of clocks (time) counted by the counter 55 and the instantaneous value of the pulsating voltage in association with each other in the storage unit constituting the microcomputer. The instantaneous value of the pulsating voltage output from the rectifier circuit 13 is monitored based on the number of clocks counted from the time when the instantaneous value detected at 51 becomes zero potential, and the count is counted. A control signal (low signal or high signal) is supplied to the first to sixth drive switch elements 30 to 35 so as to light a predetermined diode circuit among the first to sixth diode circuits 17 to 22 corresponding to the number. To do.

  In this embodiment, the first diode circuit 17 is turned on in the phase range where the pulsating voltage is 25 V to less than 50 V, and the first and second diodes are used in the phase range where the pulsating voltage is less than 50 V to 75 V. The circuits 17 to 18 are lit, the first to third diode circuits 17 to 19 are lit in the phase range in which the pulsating voltage is 75 V to less than 100 V, and the first is in the phase range in which the pulsating voltage is 100 V to less than 125 V. The first to fourth diode circuits 17 to 20 are lit and the pulsating voltage is 125 V to less than 140 V. In the phase range, the first to fifth diode circuits 17 to 21 are lit and the pulsating voltage exceeds 140 V. In the phase range, the first to sixth diode circuits 17 to 22 are set to light up.

  FIG. 3 is a time chart for explaining the operation of the lighting control circuit 17 in the light-emitting diode lighting device 10a according to the first embodiment configured as described above, and the pulsating voltage output from the rectifier circuit 13. These are shown in association with the waveform diagram of FIG. Here, in the phase range in which the pulsating voltage supplied from the rectifier circuit 13 changes from a low value to a high value, the lighting control circuit 17 responds to the change from the group on the high potential side of the light emitting diode 14 to the ground side. The light emitting diodes 14 are controlled to be lit so that the number of lights increases toward the group, and the light emitting diodes correspond to the change in the phase range in which the pulsating voltage supplied from the rectifier circuit 13 changes from a high value to a low value. The light emitting diodes 14 are controlled to be lit so that the number of lights decreases from the 14 ground side group toward the high potential side group.

  That is, until the pulsating voltage output from the rectifier circuit 13 reaches a predetermined drive start value (for example, 10 V) from the zero potential point (time t0) to a point immediately before reaching 25 V when the first diode circuit 17 lights up. (Time t0-t1) is a reset period of the switch control unit 45 by the reset circuit 54, and when the low signal is supplied from the switch control unit 45, the first to sixth drive switch elements 30 to 35 are all turned off. It has become. For this reason, the first to sixth diode circuits 17 to 22 are all turned off.

  When the pulsating voltage reaches a drive start value (for example, 10 V) (time t1), a high signal is supplied from the switch control unit 45 to each of the first to sixth drive switch elements 30 to 35, and the first signal is supplied. The sixth to sixth drive switch elements 30 to 35 are all turned on, and each light emitting diode 14 of the first diode circuit 17 is turned on when the pulsating voltage reaches 25V (time t2). That is, here, the first to sixth drive switch elements 30 to 35 are all turned on, but the first drive switch element 30 is turned on so that only the first diode circuit 17 is rectified. The output voltage from the circuit 13 is supplied, and only the first diode circuit 17 is lit.

  Next, when the pulsating current voltage reaches 50V (time t3), a low signal is supplied from the switch control unit 45 to the first drive switch element 30, and the first drive switch element 30 is turned off. The output voltage from the rectifier circuit 13 is supplied to the series circuit of the first and second diode circuits 17 and 18, and the light emitting diodes 14 of the first and second diode circuits 17 and 18 are turned on. Here, the second to sixth drive switch elements 31 to 35 are turned on, but the first drive switch element 30 is turned off and the second drive switch element 31 is turned on. The output voltage from the rectifier circuit 13 is supplied only to the first and second diode circuits 17 and 18, and only the first and second diode circuits 17 and 18 are lit.

  When the pulsating voltage reaches 75 V (time t4), a low signal is supplied from the switch control unit 45 to the second drive switch element 31 in addition to the first drive switch element 30, and the first and second drive switch elements 31 are supplied. When the drive switch elements 30 and 31 are turned off, the output voltage from the rectifier circuit 13 is supplied to the series circuit of the first to third diode circuits 17 to 19, and the first to third diodes 17 to 19 are supplied. The light emitting diodes 14 of the diode circuits 17 to 19 are turned on. Here, the third to sixth drive switch elements 32 to 35 are turned on, but the first and second drive switch elements 30 and 31 are turned off and the third drive switch element 32 is turned on. As a result, the output voltage is supplied only to the first to third diode circuits 17 to 19, and only the first to third diode circuits 17 to 19 are turned on.

  Next, when the pulsating voltage reaches 100 V (time t5), a low signal is supplied from the switch control unit 45 to the third drive switch element 32 in addition to the first and second drive switch elements 30 and 31. Thus, the output voltage from the rectifier circuit 13 is supplied to the series circuit of the first to fourth diode circuits 17 to 20 by turning off the first to third drive switch elements 30 to 32. The light emitting diodes 14 of the first to fourth diode circuits 17 to 20 are turned on. Here, the fourth to sixth drive switch elements 33 to 35 are turned on, but the first to third drive switch elements 30 to 32 are turned off and the fourth drive switch element 33 is turned on. As a result, the output voltage is supplied only to the first to fourth diode circuits 17 to 20, and only the first to fourth diode circuits 17 to 20 are turned on.

  When the pulsating voltage reaches 125 V (time t6), a low signal is supplied from the switch control unit 45 to the fourth drive switch element 33 in addition to the first to third drive switch elements 30 to 32. Since the first to fourth drive switch elements 30 to 33 are turned off, the output voltage from the rectifier circuit 13 is supplied to the series circuit of the first to fifth diode circuits 17 to 21. The light emitting diodes 14 of the first to fifth diode circuits 17 to 21 are turned on. Here, the fifth and sixth drive switch elements 34 and 35 are turned on, but the first to fourth drive switch elements 30 to 33 are turned off and the fifth drive switch element 34 is turned on. As a result, the output voltage is supplied only to the first to fifth diode circuits 17 to 21, and only the first to fifth diode circuits 17 to 21 are turned on.

  Next, when the pulsating voltage reaches 140 V (time t7), a low signal is supplied from the switch control unit 45 to the fifth drive switch element 34 in addition to the first to fourth drive switch elements 30 to 33. Thus, the output voltage from the rectifier circuit 13 is supplied to the series circuit of the first to sixth diode circuits 17 to 22 by turning off the first to fifth drive switch elements 30 to 34. The light emitting diodes 14 of the first to sixth diode circuits 17 to 22 are turned on. Note that the sixth drive switch element 35 remains on until the time t14 is reached.

  Then, when the pulsating voltage decreases to a value that divides 140 V after reaching the peak value (time t8), the switch controller 45 to the fifth drive switch element 34 in addition to the sixth drive switch element 35 are also high. When the signal is supplied, the fifth and sixth drive switch elements 34 and 35 are turned on, and the first to fourth drive switch elements 30 to 33 are turned off, so that the first to fifth diode circuits are turned on. The output voltage from the rectifier circuit 13 is supplied to the series circuits 17 to 21, the respective light emitting diodes 14 of the sixth diode circuit 22 are turned off, and the respective first to fifth diode circuits 17 to 21 are turned off. Only the light emitting diode 14 is lit. Here, the fifth and sixth drive switch elements 34 and 35 are turned on, but the first to fourth drive switch elements 30 to 33 are turned off, and the fifth drive switch element 34 is turned on. When turned on, only the first to fifth diode circuits 17 to 21 are supplied with the output voltage, and only the first to fifth diode circuits 17 to 21 are lit.

  Next, when the pulsating voltage decreases to a value that divides 125V (time t9), in addition to the fifth and sixth drive switch elements 34 and 35, the switch controller 45 also causes the fourth drive switch element 33 to go high. When the signal is supplied, the fourth to sixth drive switch elements 33 to 35 are turned on, and the first to third drive switch elements 30 to 32 are turned off, so that the first to fourth diode circuits are turned on. The output voltage from the rectifier circuit 13 is supplied to the series circuits 17 to 20, and only the light emitting diodes 14 of the first to fourth diode circuits 17 to 20 are turned on. Here, the fourth to sixth drive switch elements 33 to 35 are turned on, but the first to third drive switch elements 30 to 32 are turned off, and the fourth drive switch element 33 is turned on. When turned on, the output voltage is supplied only to the first to fourth diode circuits 17 to 20, and only the first to fourth diode circuits 17 to 20 are turned on.

  When the pulsating current voltage decreases to a value that divides 100V (time t10), in addition to the fourth to sixth drive switch elements 33 to 35, the switch control unit 45 also sends a high signal to the third drive switch element 32. Is supplied, the third to sixth drive switch elements 32 to 35 are turned on, and the first and second drive switch elements 30 and 31 are turned off, whereby the first to third diode circuits 17 are turned on. Thus, the output voltage from the rectifier circuit 13 is supplied to the series circuits of 1 to 19, and only the light emitting diodes 14 of the first to third diode circuits 17 to 19 are turned on. Here, the third to sixth drive switch elements 32 to 35 are turned on, but the first and second drive switch elements 30 and 31 are turned off, and the third drive switch element 32 is turned on. When turned on, the output voltage is supplied only to the first to third diode circuits 17 to 19, and only the first to third diode circuits 17 to 19 are turned on.

  Next, when the pulsating voltage decreases to a value that divides 75V (time t11), the switch controller 45 to the second drive switch element 31 in addition to the third to sixth drive switch elements 32 to 35 are also high. When the signal is supplied, the second to sixth drive switch elements 31 to 35 are turned on, and the first drive switch element 30 is turned off, so that the first and second diode circuits 17 and 18 are connected in series. The output voltage from the rectifier circuit 13 is supplied to the circuit, and only the light emitting diodes 14 of the first and second diode circuits 17 and 18 are lit. Here, the second to sixth drive switch elements 31 to 35 are turned on, but the first drive switch element 30 is turned off and the second drive switch element 31 is turned on. Thus, the output voltage is supplied only to the first and second diode circuits 17 and 18, and only the first and second diode circuits 17 and 18 are lit.

  When the pulsating current voltage decreases to a value that divides 50 V (time t12), in addition to the second to sixth drive switch elements 31 and 35, the switch controller 45 also sends a high signal to the first drive switch element 30. Is supplied and the first to sixth drive switch elements 30 to 35 are turned on, so that the output voltage from the rectifier circuit 13 is supplied only to the first diode circuit 17. Only each light emitting diode 14 of the circuit 17 is lit. Here, all of the first to sixth drive switch elements 30 to 35 are turned on, but the output voltage is supplied only to the first diode circuit 17 by turning on the first drive switch element 30. As a result, only the first diode circuit 17 is turned on.

  Next, the pulsating voltage is reduced to a value that divides 25V (time t13). When the pulsating voltage is further reduced, the first to sixth diode circuits 17 to 22 are brought into a non-driven state, and all the light emitting diodes 14 are turned off. It will be in the state. Then, when the driving end value is reduced to a driving end value (for example, 10 V) (time t14), a low signal is supplied from the switch control unit 45 to each of the first to sixth driving switch elements 30 to 35, and the first to sixth driving signals are supplied. The drive switch elements 30 to 35 are all turned off.

  The period in which all of the first to sixth drive switch elements 30 to 35 are turned off is continued until the pulsating voltage in the subsequent pulsating voltage waveform reaches a driving start value (for example, 10 V). That is, this period (a period from time t14 to time t1 in the next pulsating voltage waveform) is a reset period of the switch control unit 45. Thereafter, the same operation as described above is repeated for each half cycle of the pulsating voltage, whereby the first to sixth diode circuits 17 to 22 are sequentially controlled to be lit.

  According to the light emitting diode lighting device 10a according to the first embodiment configured as described above, the lighting control is performed on the first to sixth diode circuits 17 to 22 corresponding to the instantaneous value of the pulsating voltage. Since the number of lighting of the light emitting diodes 14 is increased or decreased, a plurality of light emitting diodes connected in series can be efficiently turned on by using the pulsating current voltage despite the simple circuit configuration. In addition, since at least a part of the first to sixth diode circuits 17 to 22 is turned on over a wide range of each half cycle of the pulsating voltage output from the rectifier circuit 13, Flickering of light emission can be effectively suppressed. Further, when the pulsating voltage output from the rectifier circuit 13 reaches a driving initial value (for example, 10 V), all of the first to sixth driving switch elements 30 to 35 are turned on, and then each driving switch element 30 is turned on. Since the first to sixth drive switch elements 30 to 35 are all turned on at the initial stage of driving, the drive switch elements 30 to 35 are driven and controlled one by one. Therefore, it is possible to efficiently control the lighting of each of the diode circuits 17 to 22.

  FIG. 4 is a diagram showing a circuit configuration of a light-emitting diode lighting device according to the second embodiment of the present invention. In this figure, a light emitting diode lighting device 10b is supplied with a rectifier circuit 62 connected to a sine wave AC power supply (50 Hz or 60 Hz) 60 having an effective value of 100 V via a fuse 61, and an output voltage from the rectifier circuit 62. The light emitting diode circuit 64 includes a plurality of light emitting diodes 63 connected in series in the same direction, and a lighting control circuit 65 that controls lighting of the light emitting diodes 63 of the light emitting diode circuit 64.

  The rectifier circuit 62 is configured to obtain a pulsating voltage having an output waveform similar to that in the first embodiment by performing full-wave rectification by a plurality of rectifier elements (not shown). As in the case of the first embodiment, the light-emitting diode circuit 64 has a plurality of light-emitting diodes 63 connected in series with each anode directed to the high potential side of the rectifier circuit 62 and each cathode directed to the ground side. The light emitting diodes 63 are divided into a plurality of groups with a predetermined number of continuous light emitting diodes 63 as a unit.

  That is, this light-emitting diode circuit 64 is composed of 30 light-emitting diodes 63 in this embodiment, and each of the first diode circuit 66, the second diode circuit 67, and the third light-emitting diode 63 is composed of 10 light-emitting diodes 63. The diode circuit 68 is composed of three groups, and lighting control is performed in units of groups corresponding to the instantaneous value of the pulsating voltage supplied from the rectifier circuit 13.

  The lighting control circuit 65 includes a first drive switch element 69 having a control terminal composed of a bipolar transistor connected between a connection point of the first diode circuit 66 and the second diode circuit 67 and the ground, and a second drive switch element 69. A second drive switch element 70 having a control terminal made of a bipolar transistor connected between the connection point of the diode circuit 67 and the third diode circuit 64 and the ground, and on the ground side of the third diode circuit 64 A light-emitting diode 63 at a final stage and a third drive switch element 71 with a control terminal made of a bipolar transistor connected between the ground are provided. Here, the first resistance element 72 is connected between the first drive switch element 69 and the ground, the second resistance element 73 is connected between the second drive switch element 70 and the ground, The third resistance element 74 is connected between the third drive switch element 71 and the ground.

  In addition, the lighting control circuit 65 includes an element drive control circuit 75 that controls driving (on / off control) of the first to third drive switch elements 69 to 71, a control terminal (base) of the first drive switch element 69, and a ground. , And a control terminal (a control terminal of the second drive switch element 70) and a first cut-off switch element 76 having a control terminal made of a bipolar transistor which is driven and controlled (ON / OFF control) by the element drive control circuit 75. An element cut-off circuit 78 including a second cut-off switch element 77 having a control terminal made of a bipolar transistor connected between the base and the ground and driven and controlled (ON / OFF control) by the element drive control circuit 75. And has. The element drive control circuit 75 and the element cut-off circuit 78 constitute a switch control circuit 79.

  The element drive control circuit 75 includes a first constant voltage diode 80 whose cathode is connected to the high potential side of the rectifier circuit 62, a fourth resistance element 81 connected to the anode of the first constant voltage diode 80, and a fourth resistor element. A first element drive circuit 83 comprising a series connection circuit of a second constant voltage diode 82 having a cathode connected to the resistor element 81 and an anode connected to the ground, and a cathode connected to the high potential side of the rectifier circuit 62. The third constant voltage diode 84, the fifth resistance element 85 connected to the anode of the third constant voltage diode 84, and the fifth resistance element 85 have their cathodes connected and their anodes connected to the ground. A second element driving circuit 87 composed of a series connection circuit of four constant voltage diodes 86 and a fifth constant voltage diode 88 whose cathode is connected to the high potential side of the rectifier circuit 62. The sixth resistor element 89 connected to the anode of the fifth constant voltage diode 88 and the series connection circuit of the sixth constant voltage diode 90 having the cathode connected to the sixth resistor element 89 and the anode connected to the ground And a third element drive circuit 91 comprising:

  Here, in the first element drive circuit 83, the connection point of the fourth resistance element 81 and the second constant voltage diode 82 is connected to the control terminal (base) of the first drive switch element 69, and the rectifier circuit 62. The first constant voltage diode 80 and the second constant voltage diode 82 are turned on when the pulsating voltage supplied from the base is 40 V or more, so that the control terminal (base) of the first drive switch element 69 becomes the base. A current is supplied to turn on the first drive switch element 69. Thereby, each light emitting diode 63 of the first diode circuit 66 is turned on. At this time, the first resistor element 72 and the second constant voltage diode 82 constitute a constant current circuit, so that the current flowing through the first diode circuit 66 does not exceed a specified value.

  In the second element driving circuit 87, the connection point of the fifth resistance element 85 and the fourth constant voltage diode 86 is connected to the control terminal (base) of the second driving switch element 70. When the supplied pulsating voltage is 80 V or more, the third constant voltage diode 84 and the fourth constant voltage diode 86 are turned on, whereby a base current is supplied to the control terminal (base) of the second drive switch element 70. To turn on the second drive switch element 70. In the second element driving circuit 87, the connection point of the third constant voltage diode 84 and the fifth resistance element 85 is connected to the first cutoff switch element 76 via the current limiting seventh resistance element 92. The first cut-off switch element 76 is turned on when the second drive switch element 70 is turned on, thereby turning off the first drive switch element 69.

  Thus, the first and second diode circuits 66 and 67 are connected in series, so that the light emitting diodes 63 of the first and second diode circuits 66 and 67 are turned on. At this time, the second resistance element 73 and the fourth constant voltage diode 86 constitute a constant current circuit so that the current flowing through the first and second diode circuits 65 and 66 does not exceed a specified value. . Note that the seventh resistance element 92 constitutes a part of the element cutoff circuit 78.

  In the third element driving circuit 91, the connection point of the sixth resistor element 89 and the sixth constant voltage diode 90 is connected to the control terminal (base) of the third driving switch element 71. When the supplied pulsating voltage is 120 V or higher, the fifth constant voltage diode 88 and the sixth constant voltage diode 90 are turned on, whereby the base current is supplied to the control terminal (base) of the third drive switch element 71. To turn on the third drive switch element 71. In the third element driving circuit 91, the connection point of the fifth constant voltage diode 88 and the sixth resistance element 89 is connected to the second cutoff switch element 77 via the current limiting eighth resistance element 93. The second cutoff switch element 77 is turned on when the third drive switch element 71 is turned on, and thereby the second drive switch element 70 is turned off. When the pulsating voltage supplied from the rectifier circuit 62 is 120 V or higher, the second element drive circuit 87 is also in the drive state, so the first cutoff switch element 76 is also turned on, and the first drive switch Element 69 is also off.

  As a result, the first to third diode circuits 66 to 68 are connected in series, so that the light emitting diodes 63 of the first to third diode circuits 66 to 68 are turned on. At this time, the third resistor element 74 and the sixth constant voltage diode 90 constitute a constant current circuit so that the current flowing through the first to third diode circuits 66 to 68 does not exceed the specified value. Is done. The eighth resistance element 93 constitutes a part of the element cutoff circuit 78.

That is, the element drive control circuit 75 turns on the corresponding drive switch of the first optimum third driving switch element 69 to 71 by the instantaneous value of the pulsating voltage is in the driving state exceeds a predetermined value The first element drive circuit 83, the second element drive circuit 87, and the third element drive circuit 91 are configured to be connected in parallel to the rectifier circuit 62. The element cutoff circuit 78 includes first and second drive switch elements 69 and 70 connected between the connection points of adjacent group units of the first to third diode circuits 66 to 68 and the ground. The first and second cut-off switch elements 76 and 77 that are driven and controlled by the element drive control circuit 75 are connected between the respective control terminals and the ground. When a predetermined drive switch element among the switch elements 69 to 71 is turned on, the drive switch element that is turned on at a higher potential side than the drive switch element is turned off.

  FIG. 5 is a time chart for explaining the operation of the lighting control circuit 65 in the light emitting diode lighting device 10 b according to the second embodiment configured as described above, and the pulsating voltage output from the rectifier circuit 62. These are shown in association with the waveform diagram of FIG. Here, in the phase range where the pulsating voltage supplied from the rectifier circuit 62 changes from a low value to a high value, the lighting control circuit 65 corresponds to the change from the group on the high potential side of the light emitting diode 63 to the ground side. The light emitting diodes 63 are controlled to be lit so that the number of lights increases toward the group, and in the phase range where the pulsating voltage supplied from the rectifier circuit 62 changes from a high value to a low value, the light emitting diodes correspond to the change. The light emitting diodes 63 are controlled to be lit so that the number of lights decreases from the ground side group 63 toward the high potential side group.

  That is, during the period from the zero potential point (time t0) to 40V when the first diode circuit 66 is lit (time t0-t1), each element drive circuit 83 is supplied. , 87, 91 are in a non-driven state, and no current is supplied to the control terminals of the first to third drive switch elements 69 to 71, so that the first to third drive switch elements 69 to 71 are all turned off. It has become. For this reason, the first to third diode circuits 66 to 68 are all turned off.

  When the pulsating voltage reaches 40 V at which the first diode circuit 66 is lit from the zero potential point (time t0) (time t1), the first and second constant voltage diodes 80 and 82 are turned on. The first element driving circuit 83 is in a driving state, whereby a current is supplied to the control terminal (base) of the first driving switch element 69 and the first driving switch element 69 is turned on. . For this reason, when the pulsating voltage is supplied to the first diode circuit 66, each light emitting diode 63 of the first diode circuit 66 is turned on.

  Next, when the pulsating voltage reaches 80 V (time t2), the third and fourth constant voltage diodes 84 and 86 are turned on, so that the second element driving circuit 87 is in a driving state. The current is supplied to the control terminal (base) of the second drive switch element 70, and the second drive switch element 70 is turned on. At this time, since the pulsating voltage exceeds 40 V, the first element driving circuit 83 is also in the driving state, and when only the first element driving circuit 83 is in the driving state, the first driving switch element 69 is turned on. However, as a result of the second element drive circuit 87 being in the drive state, the first cutoff switch element 76 is turned on, so that the first drive switch element 69 is turned off. Therefore, when only the second drive switch element 70 is turned on, the first and second diode circuits 66 and 67 are connected in series, and a pulsating voltage is supplied to both ends of the series connection circuit. The light emitting diodes 63 of the first and second diode circuits 66 and 67 are turned on.

  Then, when the pulsating voltage reaches 120 V (time t3), the fifth and sixth constant voltage diodes 88 and 90 are turned on, and the third element driving circuit 91 is in a driving state. The current is supplied to the control terminal (base) of the drive switch element 71 and the third drive switch element 71 is turned on. At this time, since the pulsating voltage exceeds 40 V, the first and second element drive circuits 83 and 87 are also in the drive state, and only the first and second element drive circuits 83 and 87 are in the drive state. In this case, the first drive switch 69 is turned off and the second drive switch element 70 is turned on. However, when the third element drive circuit 91 is driven, the second cutoff switch element 77 is turned on. As a result of turning on, the second drive switch element 70 is turned off. Therefore, when only the third element drive circuit 91 is turned on, the first to third diode circuits 66 to 68 are connected in series, and a pulsating voltage is supplied to both ends of the series connection circuit. Thus, the light emitting diodes 63 of the first to third diode circuits 66 to 68 are turned on.

  Next, when the pulsating current voltage reaches the peak value and then decreases to a value that divides 120V (time t4), the fifth and sixth constant voltage diodes 88 and 90 are turned off, so that the third element drive circuit As a result, the third drive switch element 71 is turned off, and the second cutoff switch element 77 is also turned off. Even if the pulsating voltage is reduced to a value that divides 120V, the first and second element driving circuits 83 and 87 are in a driving state. Therefore, when only the second drive switch element 70 is turned on, the first and second diode circuits 66 and 67 are connected in series, and a pulsating voltage is supplied to both ends of the series connection circuit. Only the light emitting diodes 63 of the first and second diode circuits 66 and 67 are lit.

  When the pulsating voltage decreases to a value that divides 80 V (time t5), the third and fourth constant voltage diodes 84 and 86 are turned off, and the second element driving circuit 87 is also in a non-driving state. As a result, the second drive switch element 70 is turned off and the first cutoff switch element 76 is also turned off. Even if the pulsating voltage decreases to a value that divides 80V, the first element driving circuit 83 is still in a driving state. Therefore, when only the first drive switch element 69 is turned on, a pulsating voltage is supplied to both ends of the first diode circuit 66, and only the light emitting diodes 63 of the first diode circuit 66 are lit. .

  Next, when the pulsating voltage becomes a value that divides 40V (time t6), the first and second constant voltage diodes 80 and 82 are turned off, so that the first element driving circuit 83 is also in a non-driving state. The first drive switch element 69 is turned off, and all the light emitting diodes 63 of the first to third diode circuits 66 to 68 are turned off. Thereafter, the same operation as described above is repeated for each half cycle of the pulsating voltage, whereby the first to third diode circuits 66 to 68 are sequentially controlled to be lit.

According to the light emitting diode lighting device 10b according to the second embodiment configured as described above,
Since the lighting number of the light emitting diodes 63 is increased or decreased by controlling the lighting of the first to third diode circuits 66 to 68 corresponding to the instantaneous value of the pulsating voltage, a simple circuit can be obtained by using the pulsating voltage. Despite the configuration, the plurality of light emitting diodes 63 connected in series can be efficiently lit. In addition, since at least some of the first to third diode circuits 65 to 67 are lit over a wide range of each half cycle of the pulsating voltage output from the rectifier circuit 62, Flickering of light emission can be effectively suppressed.

  FIG. 6 is a diagram showing a circuit configuration of a light-emitting diode lighting device according to the third embodiment of the present invention. In this figure, a light emitting diode lighting device 10c is supplied with a rectifier circuit 97 connected to a sinusoidal AC power supply (50 Hz or 60 Hz) 95 having an effective value of 100 V via a fuse 96, and an output voltage from the rectifier circuit 97. Therefore, a light emitting diode circuit 99 configured by connecting a plurality of light emitting diodes 98 in series in the same direction, and an instantaneous value of a pulsating voltage (in series) connected to the light emitting diode circuit 99 and supplied from a rectifier circuit 97 ( And a variable impedance circuit 100 for making the current flowing through the light emitting diode circuit 99 substantially constant by varying the impedance corresponding to the voltage value).

  The rectifier circuit 97 is configured to obtain a pulsating voltage having an output waveform similar to that of the first and second embodiments by performing full-wave rectification by a plurality of rectifier elements (not shown). is there. In the light emitting diode circuit 99, a plurality (18 in this case, those having a driving voltage of 3.6V) of light emitting diodes 98 are connected in series with each anode directed to the high potential side of the rectifier circuit 97 and each cathode directed to the ground side. It is connected and set to light up when the pulsating voltage becomes, for example, 70V or more.

  In the phase range where the instantaneous value of the pulsating current voltage is a predetermined value (70 V in this case) or more, the variable impedance circuit 100 is in the phase range where the pulsating voltage supplied from the rectifier circuit 97 changes from a low value to a high value. The impedance value (resistance value) increases corresponding to the change, and the impedance value (resistance value) decreases corresponding to the change in the phase range where the pulsating voltage changes from a high value to a low value. The resistor circuit 101 connected in series to the light emitting diode circuit 99 and the resistance control circuit 108 that varies the resistance value (combined resistance value) of the resistor circuit 101 according to the instantaneous value of the pulsating voltage.

  The resistance circuit 101 is configured by connecting a first resistance element 103, a second resistance element 104, a third resistance element 105, and a fourth resistance element 106 in series. The resistance control circuit 108 controls the first short-circuit switch element 107 with a control terminal such as a MOSFET connected to both ends of the second resistance element 104 and the MOSFET connected to both ends of the third resistance element 105. A second short-circuit switch element 108 with a terminal; a third short-circuit switch element 109 with a control terminal such as a MOSFET connected to both ends of the fourth resistance element 106; and these first to third short-circuit switches. A switch control unit 110 composed of a microcomputer for controlling on / off of the first to third short-circuit switch elements 107 to 109 by supplying a control signal to the control terminals of the elements 107 to 109, a resistance element 111, a capacitor 112, The pulsating voltage output from the rectifier circuit 97 is converted to a DC voltage having a predetermined value (for example, 5 The pulsating voltage output from the rectifier circuit 97 is configured by a series connection circuit of a plurality of resistance elements 113 and 114 connected to the rectifier circuit 97. And a voltage detection circuit 115 for detecting an instantaneous value (voltage value). The switch control unit 110, the voltage supply circuit 113, and the voltage detection circuit 115 constitute a switch control circuit 117.

  Here, the switch control unit 110 includes a clock oscillation circuit 118 that generates a clock signal for operating the switch control unit 110, and a reset circuit that resets the operation of the switch control unit 110 when the power is input or when the power is shut off. 119 and a counter 120 that counts the number of clocks generated by the clock oscillation circuit 118, and a time discriminating unit that discriminates whether or not the time counted by the counter 120 has reached a predetermined value. The pulsating current detected by the voltage detection circuit 116 and the switching element control unit that controls the on / off of the first to third short-circuiting switching elements 107 to 109 by supplying a control signal to the control terminal corresponding to the detected time Reference value in the comparison circuit where the instantaneous voltage value is provided in the interface circuit (not shown) And a respective function realizing unit as a voltage determination unit for determining whether it is zero potential based on the comparison result of the.

  That is, the switch control unit 110 stores the number of clocks (time) counted by the counter 120 and the instantaneous value of the pulsating voltage in association with each other in the storage unit constituting the microcomputer. The instantaneous value of the pulsating voltage output from the rectifier circuit 97 is monitored based on the number of clocks counted from the time when the instantaneous value detected at 116 becomes zero potential. A control signal (low signal or high signal) is supplied to the first to third short-circuit switch elements 107 to 109 corresponding to the number.

  FIG. 7 is a time chart for explaining the operation of the variable impedance circuit 100 in the light emitting diode lighting device 10 c according to the third embodiment configured as described above, and the pulsating voltage output from the rectifier circuit 97. These are shown in association with the waveform diagram of FIG. Here, as described above, the variable impedance circuit 100 has a phase in which the pulsating voltage changes from a low value to a high value in a phase range in which the instantaneous value of the pulsating voltage supplied from the rectifying circuit 97 is equal to or greater than a predetermined value. In the range, the resistance value (impedance value) of the resistance circuit 101 is increased corresponding to the change, and in the phase range where the resistance value is changed from a high value to a low value, the resistance value (impedance value) of the resistance circuit 101 is corresponding to the change. ) Is made low so that the current flowing through the light emitting diode circuit 99 falls within a substantially constant range, thereby controlling the lighting of the light emitting diode 98.

  That is, the first to third short-circuit switch elements 107 from the switch control unit 110 until the pulsating voltage output from the rectifier circuit 97 reaches 70 V from the zero potential point (time t0) (time t0-t1). A high signal is supplied to the first to third short-circuit switch elements 107 to 109, so that all the first to third short-circuit switch elements 107 to 109 are turned on. Therefore, the second to fourth resistance elements 104 to 106 of the resistance circuit 101 are all short-circuited, and only the first resistance element 103 is connected to the light-emitting diode circuit 99. In this embodiment, the light emitting diode circuit 99 is in a non-driven state until 70V is reached, and the resistance value of the first resistance element 103 is set so that each light emitting diode 98 is not lit. For this reason, in the period of time t0-t1, each light emitting diode 98 remains unlit.

  When the pulsating voltage reaches 70 V (time t1), the first to third short-circuit switch elements 107 to 109 are set to be turned on even at this time. The pulsating voltage is supplied through the resistance element 103, and each light emitting diode 98 is lit. Since the circuit current is regulated by the presence of the first resistance element 103, no current exceeding the specified value flows through the light emitting diode circuit 99.

  Next, when the pulsating current voltage reaches 100 V (time t2), a low signal is supplied from the switch control unit 110 to the first short-circuit switch element 107, and only the first short-circuit switch element 107 is turned off. The flowing voltage is supplied to the light emitting diode circuit 99 via the first and second resistance elements 103 and 104. Here, each of the resistance values of the first and second resistance elements 103 and 104 emits a current having a magnitude within substantially the same range as when the light-emitting diode circuit 99 is energized through the first resistance element 103. Since it is set to flow through the diode circuit 99, each light emitting diode 98 is lit with substantially the same brightness even if the pulsating voltage rises to 100V or higher.

  When the pulsating voltage reaches 125 V (time t3), a low signal is supplied from the switch control unit 110 to the second short-circuit switch element 108 in addition to the first short-circuit switch element 107, and the first and second When the short-circuit switch elements 107 to 109 are turned off, the pulsating voltage is supplied to the light emitting diode circuit 99 via the first to third resistance elements 103 to 105. Here, each of the resistance values of the first to third resistance elements 103 and 105 emits a current having a magnitude within substantially the same range as when the light-emitting diode circuit 99 is energized through the first resistance element 103. Since it is set to flow through the diode circuit 99, each light emitting diode 98 is lit with substantially the same brightness even when the pulsating voltage rises to 125V or higher.

  Next, when the pulsating voltage reaches 140 V (time t4), a low signal is supplied from the switch control unit 110 to the third short-circuit switch element 109 in addition to the first and second short-circuit switch elements 107 and 108. When the first to third short-circuit switch elements 107 to 109 are turned off, the pulsating voltage is supplied to the light emitting diode circuit 99 via the first to fourth resistance elements 103 to 106. Here, each of the resistance values of the first to fourth resistance elements 103 to 106 emits a current having a magnitude within substantially the same range as when the light-emitting diode circuit 99 is energized through the first resistance element 103. Since it is set to flow through the diode circuit 99, each light emitting diode 98 is lit with substantially the same brightness even when the pulsating voltage rises to 140V or higher.

  When the pulsating voltage decreases to a value that divides 140 V after reaching the peak value (time t5), a high signal is supplied from the switch control unit 110 to the third short-circuit switch element 109, and the third short-circuit switch element When 109 is turned on, the pulsating voltage is supplied to the light emitting diode circuit 99 via the first to third resistance elements 103 to 105. Here, each of the resistance values of the first to third resistance elements 103 to 105 emits a current having a magnitude within the same range as when the light-emitting diode circuit 99 is energized through the first resistance element 103. Since it is set to flow through the diode circuit 99, each light emitting diode 98 is lit with substantially the same brightness even if the pulsating voltage is reduced to 140V or less.

  Next, when the pulsating voltage decreases to a value that divides 125V (time t6), a high signal is supplied from the switch control unit 110 to the second and third short-circuit switch elements 108 and 109, and the second and third When the short-circuit switch elements 107 to 109 are turned on, the pulsating voltage is supplied to the light emitting diode circuit 99 via the first and second resistance elements 103 and 104. Here, each of the resistance values of the first and second resistance elements 103 and 104 emits a current having a magnitude within substantially the same range as when the light-emitting diode circuit 99 is energized through the first resistance element 103. Since it is set to flow through the diode circuit 99, each light emitting diode 98 is lit with substantially the same brightness even when the pulsating voltage is reduced to 125V or less.

  Next, when the pulsating voltage decreases to a value that divides 100 V (time t7), a high signal is supplied from the switch control unit 110 to the first to third short-circuit switch elements 107 to 109, and the first to third short-circuits are performed. When the switch elements 107 to 109 are turned on, the pulsating voltage is supplied to the light emitting diode circuit 99 only through the first resistance element 103, and each light emitting diode 98 is turned on.

  When the pulsating voltage decreases to a value that divides 70 V (time t8), the light emitting diode circuit 99 is in a non-driven state, and all the light emitting diodes 98 are turned off. Thereafter, the light emitting diode circuit 99 is controlled to be turned on by repeating the same operation as described above for each half cycle of the pulsating voltage.

  According to the light emitting diode lighting device 10c according to the third embodiment configured as described above, a substantially constant current flows through the light emitting diode circuit 99 in a phase range in which the instantaneous value of the pulsating voltage exceeds a predetermined value. Since the impedance value is increased or decreased in accordance with the instantaneous value of the pulsating voltage, the lighting control is efficiently performed for the plurality of light emitting diodes 98 connected in series despite the simple circuit configuration by using the pulsating voltage. be able to. Further, since the light emitting diode 98 is turned on over a wide range of each half cycle of the pulsating voltage output from the rectifier circuit 97, flickering of light emission and the like can be effectively suppressed.

  FIG. 8 is a diagram showing a circuit configuration of a light-emitting diode lighting device according to the fourth embodiment of the present invention. In this figure, the LED lighting device 10d is supplied with a rectifier circuit 123 connected to a sinusoidal AC power source (50 Hz or 60 Hz) 121 having an effective value of 100 V via a fuse 122, and an output voltage from the rectifier circuit 123. The light-emitting diode circuit 125 is configured by connecting a plurality of light-emitting diodes 124 in series in the same direction, and the instantaneous value of the pulsating voltage that is connected in series to the light-emitting diode circuit 125 and supplied from the rectifier circuit 123 ( And a variable impedance circuit 126 that makes the current flowing through the light emitting diode circuit 125 substantially constant by varying the impedance in accordance with the voltage value.

  The rectifier circuit 123 is configured to obtain a pulsating voltage having an output waveform similar to that of the first to third embodiments by performing full-wave rectification by a plurality of rectifier elements (not shown). is there. The light-emitting diode circuit 125 includes a plurality of (here, 18 drive voltages of 3.6 V) light-emitting diodes 124 each having its anode directed to the high potential side of the rectifier circuit 123 and each cathode directed to the ground side in series. It is connected and set to light up when the pulsating voltage becomes equal to or higher than a predetermined value (here, 70V). The variable impedance circuit 126 corresponds to the instantaneous value of the pulsating voltage so that a substantially constant current can flow through the light-emitting diode circuit 125 in a phase range where the pulsating voltage becomes a predetermined value (70 V or more). Thus, the impedance value is variable (adjusted).

  That is, the variable impedance circuit 126 is similar to the third embodiment in that the pulsating voltage supplied from the rectifier circuit 123 is low to high in the phase range where the instantaneous value of the pulsating voltage exceeds a predetermined value. In the phase range in which the impedance voltage (resistance value) increases in response to the change, the impedance value (resistance value) corresponds to the change in the phase range in which the pulsating voltage changes from a high value to a low value. A resistance circuit 127 connected in series to the light emitting diode circuit 125, and a resistance control circuit 128 that varies the resistance value of the resistance circuit 127 according to the instantaneous value of the pulsating voltage. Yes.

  The resistance circuit 127 is configured by connecting a first resistance element 131, a second resistance element 132, a third resistance element 133, and a fourth resistance element 134 in series. The resistance control circuit 128 includes a first drive switch element 135 having a control terminal made of a bipolar transistor connected between the connection point of the first resistance element 131 and the second resistance element 132 and the ground, A second drive switch element 136 having a control terminal made of a bipolar transistor connected between the connection point of the first resistance element 132 and the third resistance element 133 and the ground, and the third resistance element 133 and the ground. A third drive switch element 137 with a control terminal made of a bipolar transistor connected between them, and a fourth drive switch with a control terminal made of a bipolar transistor connected between the fourth resistance element 134 and the ground And an element 138.

  In addition, the resistance control circuit 128 includes an element drive control circuit 140 that controls driving (on / off control) of the first to fourth drive switch elements 135 to 138, a control terminal (base) of the first drive switch element 135, and a ground. And a control terminal (base) of the first cut-off switch element 141 and the second drive switch element 136 having a control terminal composed of a bipolar transistor that is connected between the control terminals and is controlled by the element drive control circuit 140 (on / off control). And the control terminals of the second cutoff switch element 142 and the third drive switch element 137 with a control terminal made of a bipolar transistor that is connected between the power supply and the ground and is driven and controlled (ON / OFF controlled) by the element drive control circuit 140. Connected between the base and the ground, and drive control (ON) by the element drive control circuit 140 And a device blocking circuit 144 is configured to include a third cutoff switch element 143 with a control terminal consisting of full control) by the bipolar transistor. The element drive control circuit 140 and the element cutoff circuit 144 constitute a switch control circuit 145.

  The element drive control circuit 140 is provided closer to the rectifier circuit 123 than the light-emitting diode circuit 125, and includes a first constant voltage diode 147 having a cathode connected to the high potential side of the rectifier circuit 123, and a first constant voltage diode 147. A first resistor comprising a fifth resistor element 148 connected to the cathode of the voltage diode 147 and a second connected constant voltage diode 149 having a cathode connected to the fifth resistor element 148 and an anode connected to the ground. Element driving circuit 150, the third constant voltage diode 151 whose cathode is connected to the high potential side of the rectifier circuit 123, the sixth resistance element 152 connected to the cathode of the third constant voltage diode 151, and the sixth Of the fourth constant voltage diode 153 having a cathode connected to the resistor element 152 and an anode connected to the ground. A second element drive circuit 154; a fifth constant voltage diode 155 whose cathode is connected to the high potential side of the rectifier circuit 123; a seventh resistor element 156 connected to the cathode of the fifth constant voltage diode 155; A third element drive circuit 158 comprising a series connection circuit of a sixth constant voltage diode 157 having a cathode connected to the seventh resistance element 156 and an anode connected to the ground, and a cathode connected to the high potential side of the rectifier circuit 123 The seventh constant voltage diode 159 connected to the cathode, the eighth resistor element 160 connected to the cathode of the seventh constant voltage diode 159 and the eighth resistor element 160 are connected to the cathode, and the anode is connected to the ground. And a fourth element driving circuit 162 including a series connection circuit of eighth constant voltage diodes 161.

  Here, in the first element driving circuit 150, the connection point of the fifth resistance element 148 and the second constant voltage diode 149 is connected to the control terminal (base) of the first driving switch element 135, and the rectifier circuit 123. The first constant-voltage diode 147 and the second constant-voltage diode 149 are turned on when the pulsating voltage supplied from the base is 70 V or more, so that the control terminal (base) of the first drive switch element 135 becomes the base. A current is supplied to turn on the first drive switch element 135. As a result, the pulsating voltage is supplied to the light emitting diode circuit 125 via the first resistance element 131, and each light emitting diode 124 of the light emitting diode circuit 125 is turned on.

  The second element driving circuit 154 has a connection point between the sixth resistance element 152 and the fourth constant voltage diode 153 connected to the control terminal (base) of the second driving switch element 136, and When the supplied pulsating voltage is 100 V or higher, the third constant voltage diode 151 and the fourth constant voltage diode 153 are turned on, whereby the base current is supplied to the control terminal (base) of the second drive switch element 136. To turn on the second drive switch element 136. Further, the second element driving circuit 154 includes a first cutoff switch element via a ninth resistance element 164 in which a connection point between the third constant voltage diode 151 and the sixth resistance element 152 is a current limiting resistor. 141 is connected to the control terminal (base) 141, and when the second drive switch element 136 is turned on, the first cutoff switch element 141 is turned on, thereby turning off the first drive switch element 135.

  As a result, the first and second resistance elements 131 and 132 are connected in series, whereby a pulsating voltage is supplied to the light emitting diode circuit 125 via the first and second resistance elements 131 and 132, and the light emitting diode circuit Each of the 125 light emitting diodes 124 is lit. The ninth resistance element 164 constitutes a part of the element cutoff circuit 144.

  The third element driving circuit 158 has a connection point between the seventh resistance element 156 and the sixth constant voltage diode 157 connected to the control terminal (base) of the third driving switch element 136, and When the supplied pulsating voltage is 125 V or higher, the fifth constant voltage diode 155 and the sixth constant voltage diode 157 are turned on, whereby the base current is supplied to the control terminal (base) of the third drive switch element 137. To turn on the third drive switch element 137. In addition, the third element driving circuit 158 includes a second cutoff switch element via a tenth resistance element 165 whose connection point between the fifth constant voltage diode 155 and the seventh resistance element 156 is a current limiting resistance. The second cut-off switch element 142 is turned on when the third drive switch element 137 is turned on, thereby turning the second drive switch element 136 off.

  Here, when the pulsating voltage supplied from the rectifier circuit 123 is 125 V or more, the first cutoff switch element 141 is also turned on, and the first drive switch element 135 is also turned off. Therefore, the pulsating voltage is supplied to the light emitting diode circuit 125 via the first to third resistance elements 131 to 133 by connecting the first to third resistance elements 131 to 133 in series, and the light emitting diode circuit Each of the 125 light emitting diodes 124 is lit. The tenth resistance element 165 constitutes a part of the element cutoff circuit 144.

  The fourth element driving circuit 162 has a connection point between the eighth resistance element 160 and the eighth constant voltage diode 161 connected to the control terminal (base) of the fourth driving switch element 138, and When the supplied pulsating voltage is 140 V or higher, the seventh constant voltage diode 159 and the eighth constant voltage diode 161 are turned on, so that the base current is supplied to the control terminal (base) of the fourth drive switch element 138. To turn on the fourth drive switch element 138. The fourth element driving circuit 162 includes a third cutoff switch element via an eleventh resistance element 166 whose connection point between the seventh constant voltage diode 159 and the eighth resistance element 160 is a current limiting resistor. 143 is connected to the control terminal (base) 143, and when the fourth drive switch element 138 is turned on, the third cutoff switch element 143 is turned on, thereby turning off the third drive switch element 137.

  Here, when the pulsating voltage supplied from the rectifier circuit 123 is 140 V or more, the first and second cutoff switch elements 141 and 142 are also turned on, and the first and second drive switch elements 135 and 136 are also turned on. Is turned off. Therefore, the pulsating voltage is supplied to the light emitting diode circuit 125 via the first to fourth resistance elements 131 to 134 by connecting the first to fourth resistance elements 131 to 134 in series, and the light emitting diode circuit Each of the 125 light emitting diodes 124 is lit. Note that the eleventh resistance element 166 constitutes a part of the element cutoff circuit 144.

That is, the element drive control circuit 140 are each on a corresponding drive switch of the first optimum fourth driving switch element 135 through 138 by the instantaneous value of the pulsating voltage is in the driving state exceeds a predetermined value The first element driving circuit 150, the second element driving circuit 154, the third element driving circuit 158, and the fourth element driving circuit 162 are configured to be connected in parallel to the rectifier circuit 123. . In addition, the element blocking circuit 144 includes first to third drive switch elements 135 to 137 connected between connection points of the adjacent resistance elements of the first to fourth resistance elements 131 to 134 and the ground. The first to third cutoff switch elements that are driven and controlled by the control signals supplied from the element drive control circuit 140 via the ninth to eleventh resistance elements 164 to 166 between the control terminals of the first and second control terminals 140 141 to 143 are connected, and when a predetermined drive switch element among the first to fourth drive switch elements 135 to 138 is turned on, the drive switch element is turned on at a higher potential side. The drive switch element is turned off.

  FIG. 9 is a time chart for explaining the operation of the variable impedance circuit 128 in the light emitting diode lighting device 10 d according to the fourth embodiment configured as described above, and the pulsating voltage output from the rectifier circuit 123. These are shown in association with the waveform diagram of FIG. Here, as described above, the variable impedance circuit 128 has a resistance value (impedance) of the resistance circuit 127 corresponding to the change in the phase range in which the pulsating voltage supplied from the rectifier circuit 123 changes from a low value to a high value. In the phase range in which the pulsating voltage supplied from the rectifier circuit 123 changes from a high value to a low value, the resistance value (impedance value) of the resistor circuit 127 is low corresponding to the change. As a result, the current flowing through the light emitting diode circuit 125 falls within a substantially constant range, and thereby the lighting of the light emitting diode 124 is controlled.

  That is, during the period from the zero potential point (time t0) to 70V when each light emitting diode 124 of the light emitting diode circuit 125 is turned on (time t0-t1), The second, third, and fourth element drive circuits 150, 154, 158, and 162 are not driven, and no current is supplied to the control terminals of the first to fourth drive switch elements 135 to 138. The first to fourth drive switch elements 135 to 138 are all off.

  When the pulsating voltage reaches 70 V (time t1), the first and second constant voltage diodes 147 and 149 are turned on, so that the first element driving circuit 150 enters the driving state. Current is supplied to the control terminal (base) of the drive switch element 135, and the first drive switch element 135 is turned on. Accordingly, the pulsating voltage is supplied to the light emitting diode circuit 125 via the first resistance element 131, and each light emitting diode 124 is turned on. Here, the first resistance element 131 is set to a value that prevents a current exceeding a specified value from flowing through each light emitting diode 124.

  Next, when the pulsating voltage reaches 100 V (time t2), the third and fourth constant voltage diodes 151 and 153 are turned on, so that the second element driving circuit 154 enters the driving state. The current is supplied to the control terminal (base) of the second drive switch element 136, and the second drive switch element 136 is turned on. At this time, since the pulsating voltage exceeds 70 V, the first element driving circuit 150 is also in a driving state, but when the second element driving circuit 154 is in a driving state, the first cutoff switch element 142 is turned on. As a result, the first drive switch element 135 is turned off.

  Therefore, when only the second drive switch element 136 is turned on, the pulsating voltage is supplied to the light emitting diode circuit 125 via the first and second resistance elements 131 and 132. Here, each of the resistance values of the first and second resistance elements 131 and 132 emits a current having a magnitude within substantially the same range as when the light-emitting diode circuit 125 is energized through the first resistance element 131. Since it is set to flow through the diode circuit 125, each light emitting diode 124 is lit with substantially the same brightness even if the pulsating voltage rises to 100V.

  Then, when the pulsating voltage reaches 125 V (time t3), the fifth and sixth constant voltage diodes 155 and 157 are turned on, so that the third element driving circuit 158 enters the driving state. Current is supplied to the control terminal (base) of the drive switch element 137, and the third drive switch element 137 is turned on. At this time, since the pulsating voltage exceeds 70 V, the first and second element drive circuits 150 and 154 are also driven, respectively, but the second element drive circuit 158 is driven and the second element drive circuit 158 is driven. When the cutoff switch element 142 is turned on, the second drive switch element 136 is turned off. Note that the first drive switch element 135 is also turned off when the second element drive circuit 154 is driven.

  Therefore, when only the third drive switch element 137 is turned on, the pulsating voltage is supplied to the light emitting diode circuit 125 via the first to third resistance elements 131 to 133. Here, each of the resistance values of the first to third resistance elements 131 to 133 emits a current having a magnitude within substantially the same range as when the light-emitting diode circuit 125 is energized through the first resistance element 131. Since it is set to flow through the diode circuit 125, each light emitting diode 124 is lit with substantially the same brightness even if the pulsating voltage rises to 125V.

  Next, when the pulsating current voltage reaches 140 V (time t4), the seventh and eighth constant voltage diodes 159 and 161 are turned on, and the fourth element driving circuit 162 is driven, whereby the fourth element driving circuit 162 is driven. Current is supplied to the control terminal (base) of the fourth drive switch element 138, and the fourth drive switch element 138 is turned on. At this time, since the pulsating voltage exceeds 70 V, the first, second, and third element driving circuits 150, 154, and 158 are also driven, but the fourth element driving circuit 162 is driven. Thus, the third cutoff switch element 143 is turned on, and the third drive switch element 137 is turned off. The first and second drive switch elements 135 and 136 are also turned off when the second and third element drive circuits 154 and 158 are in the drive state.

  Therefore, when only the fourth drive switch element 138 is turned on, the pulsating voltage is supplied to the light emitting diode circuit 125 via the first to fourth resistance elements 131 to 134. Here, each of the resistance values of the first to fourth resistance elements 131 to 134 emits a current having a magnitude within substantially the same range as when the light-emitting diode circuit 125 is energized through the first resistance element 131. Since it is set to flow through the diode circuit 125, each light emitting diode 124 is lit with substantially the same brightness even when the pulsating voltage rises to 140V.

  When the pulsating current voltage reaches a peak value and then decreases to a value that divides 140 V (time t5), the seventh and eighth constant voltage diodes 159 and 161 are turned off, and the fourth element driving circuit 162 is turned off. As a result, the fourth drive switch element 138 is turned off, and the third cutoff switch element 143 is also turned off. Even if the pulsating voltage decreases to a value that divides 140V, the first, second, and third element driving circuits 150, 154, and 158 are in a driving state.

  Therefore, when only the third drive switch element 137 is turned on, the pulsating voltage is supplied to the light emitting diode circuit 125 via the first to third resistance elements 131 to 133. Here, each of the resistance values of the first to third resistance elements 131 to 133 emits a current having a magnitude within substantially the same range as when the light-emitting diode circuit 125 is energized through the first resistance element 131. Since it is set to flow through the diode circuit 125, each light emitting diode 124 is lit with substantially the same brightness until the pulsating voltage is reduced to 125V.

  Next, when the pulsating voltage decreases to a value that divides 125V (time t6), the fifth and sixth constant voltage diodes 155 and 157 are turned off, and the third element driving circuit 158 is brought into a non-driving state. As a result, the third drive switch element 137 is turned off, and the second cutoff switch element 142 is also turned off. Even if the pulsating voltage is reduced to 125V, the first and second element driving circuits 150 and 154 are in a driving state.

  Therefore, when only the second drive switch element 136 is turned on, the pulsating voltage is supplied to the light emitting diode circuit 125 via the first and second resistance elements 131 and 132. Here, each of the resistance values of the first and second resistance elements 131 and 132 emits a current having a magnitude within substantially the same range as when the light-emitting diode circuit 125 is energized through the first resistance element 131. Since it is set to flow through the diode circuit 125, each light emitting diode 124 is lit with substantially the same brightness until the pulsating voltage is reduced to 100V.

  Then, when the pulsating voltage decreases to a value that divides 100V (time t7), the third and fourth constant voltage diodes 151 and 153 are turned off, and the second element driving circuit 154 enters a non-driving state. As a result, the second drive switch element 136 is turned off, and the first cutoff switch element 141 is also turned off. Even if the pulsating voltage is reduced to 100 V, the first element driving circuit 150 is in a driving state. Therefore, when only the first drive switch element 135 is turned on, the pulsating voltage is supplied to the light emitting diode circuit 125 only through the first resistance element 131, and each light emitting diode 124 is turned on.

  When the pulsating voltage decreases to a value that divides 70V (time t8), the first and second constant voltage diodes 147 and 149 are turned off, so that the first element driving circuit 150 enters a non-driving state. Since the light emitting diode circuit 125 is also in a non-driven state, all the light emitting diodes 124 are turned off. Thereafter, the light emitting diode circuit 125 is controlled to be turned on by repeating the same operation as described above for each half cycle of the pulsating voltage.

  According to the light emitting diode lighting device 10d according to the fourth embodiment configured as described above, a substantially constant current flows through the light emitting diode circuit 125 in a phase range in which the instantaneous value of the pulsating voltage exceeds a predetermined value. Since the impedance value is increased or decreased in accordance with the instantaneous value of the pulsating voltage, lighting control is efficiently performed on the plurality of light emitting diodes 124 connected in series despite the simple circuit configuration using the pulsating voltage. be able to. Further, since the plurality of light emitting diodes 124 are turned on over a wide range of each half cycle of the pulsating voltage output from the rectifier circuit 123, flickering of light emission and the like can be effectively suppressed.

  Since the present invention is configured as shown in the first to fourth embodiments as described above, a plurality of light emitting diodes connected in series can be efficiently lit with a simple circuit configuration. . In addition, this invention is not limited to the thing of the said 1st thru | or 4th embodiment, The various deformation | transformation aspects described below can be employ | adopted as needed.

  (1) In the light-emitting diode lighting device 10a according to the first embodiment, the light-emitting diode circuit 15 is composed of six diode circuits (groups) of the first to sixth diode circuits 17 to 22. However, it is not limited to this. The light emitting diode circuit 64 may be composed of, for example, two diode circuits, or may be composed of seven or more diode circuits. Further, the number of light-emitting diodes 14 connected in series is not limited to that of the embodiment, and can be set as appropriate according to the rated value of the current that can be passed through the light-emitting diode 14.

  (2) In the light emitting diode lighting device 10a according to the first embodiment, the first to fifth intermediate resistance elements 23 to 27 are provided between adjacent diode circuits of the light emitting diode circuit 15. This is not a limitation.

  For example, the current limiting resistor element 16 having the above configuration is provided between the first drive switch element 30 and the ground, and the first intermediate resistor element 23 is the current limiting resistor element 16 and the first intermediate resistor element 23. Is replaced with a resistor element having a combined resistance value, and provided between the second drive switch element 31 and the ground, and the second intermediate resistor element 24 is connected to the current limiting resistor element 16 and the second intermediate resistor element 24. Is replaced with a resistor element having a combined resistance value, and is provided between the third drive switch element 32 and the ground, and the third intermediate resistor element 25 is replaced with the current limiting resistor element 16 and the third intermediate resistor element 25. The fourth drive switch element 33 is provided between the ground and the fourth drive switch element 33 in place of the resistor element having the combined resistance value, and the fourth intermediate resistor element 26 is connected to the current limiting resistor element 16 and the fourth intermediate resistor element 26. It replaces with a resistance element having a combined resistance value and is provided between the fifth drive switch element 34 and the ground, and a fifth intermediate resistance element 27 is combined with the current limiting resistance element 16 and the fifth intermediate resistance element 27. Instead of a resistance element having a resistance value, it may be provided between the sixth drive switch element 35 and the ground. Even in such a case, the operation is equivalent to the circuit shown in FIG.

  Further, for example, a known constant current circuit (current limiting element) constituted by a transistor or the like may be inserted at the position of the current limiting resistance element 16 in the above configuration. The limiting resistance element 16 and the first to fifth intermediate resistance elements 23 to 27 are not necessary. In short, a current limiting element (current limiting circuit) composed of a current limiting resistor element, a constant current circuit, or the like is inserted in the lighting circuit so that a current exceeding a specified value does not flow through each light emitting diode 14. It only has to be done.

  For this reason, in the present invention, the first drive switch element 30 is connected to the first diode circuit 17 and the second diode circuit 18 regardless of the presence or absence of the first to fifth intermediate resistance elements 23 to 27. Between the point and the ground, the second drive switch element 31 is connected between the connection point of the second diode circuit 18 and the third diode circuit 19 and the ground, and the third drive switch element 32 is The fourth drive switch element 33 is connected between the connection point of the third diode circuit 19 and the fourth diode circuit 20 and the ground, and the connection point of the fourth diode circuit 20 and the fifth diode circuit 21 and the ground. In the meantime, it is assumed that the fifth drive switch element 34 is provided between the connection point of the fifth diode circuit 21 and the sixth diode circuit 22 and the ground.

  In short, the first drive switch element 30 is provided between the light-emitting diode 14 on the ground side of the light-emitting diode 14 of the first diode circuit 17 and the ground, and the second drive switch element 31 is Among the light emitting diodes 14 of the second diode circuit 18, the third drive switch element 32 is between the light emitting diodes 14 of the third diode circuit 19 between the light emitting diode 14 at the final stage on the ground side and the ground. Between the light-emitting diode 14 at the final stage on the ground side and the ground, the fourth drive switch element 33 is connected to the ground-side light-emitting diode 14 at the ground side of the light-emitting diodes 14 of the fourth diode circuit 20 and the ground. Between the light emitting diodes 14 of the fifth diode circuit 21 on the ground side. May I respectively provided between the light emitting diode 14 and the ground of the last stage that.

  (3) In the light emitting diode lighting device 10a according to the first embodiment, when the pulsating voltage supplied from the rectifier circuit 13 reaches the drive initial value (for example, 10V) at time t1, the first to first The six drive switch elements 30 to 35 are all turned on, and then the drive switch elements 30 to 35 are sequentially turned off. However, the present invention is not limited to this.

  For example, only the first drive switch element 30 is turned on when the drive initial value is reached at time t1 or t2, and only the second drive switch element 31 is turned on when time t3 is reached, at time t4. Only the third drive switch element 32 is turned on when reaching, only the fourth drive switch element 33 is turned on when time t5 is reached, and only the fifth drive switch element 34 is reached when time t6 is reached. When the time t7 is reached, only the sixth drive switch element 35 is turned on. On the other hand, when the time t8 is reached, only the fifth drive switch element 34 is turned on and the time t9 is reached. Only the fourth drive switch element 33 is turned on, only the third drive switch element 32 is turned on when time t10 is reached, and the second drive switch element 32 is turned on when time t11 is reached. Only the element 31 is turned on, only the first drive switch element 30 is turned on when the time t12 is reached, and all the first to sixth drive switch elements 30 to 35 are turned off when the time t13 is reached. You may do it.

  (4) In the light emitting diode lighting device 10a according to the first embodiment, the sixth drive switch element 35 is provided between the light emitting diode 14 at the final stage of the sixth diode circuit 22 and the ground. However, this is not a limitation. For example, the light emitting diode 14 at the final stage of the sixth diode circuit 22 may be directly connected to the ground without providing the sixth drive switch element 35 between the sixth diode circuit 22 and the ground. Good. In this case, in addition to having the same effects as the light emitting diode lighting device 10a according to the first embodiment, the number of parts can be reduced and the sixth drive switch element 35 can be controlled. Since it becomes unnecessary, the control operation can be simplified. In short, at least a drive switch element is connected between each connection point of adjacent group units of a plurality of groups divided by a predetermined number of continuous light emitting diodes 14 among the plurality of light emitting diodes 14 and the ground. It only has to be.

  (5) In the light emitting diode lighting device 10a according to the first embodiment, the switch control unit 45 uses the counter 55 to count the instantaneous value of the pulsating voltage supplied from the rectifier circuit 13 (time). Although monitoring is performed, the present invention is not limited to this. For example, the instantaneous value of the pulsating voltage may be directly monitored by comparing the output from the voltage detection circuit 51 with a reference value using a comparison circuit.

  (6) In the light-emitting diode lighting device 10a according to the first embodiment, the plurality of light-emitting diodes 14 connected in series are divided into a plurality of groups of first to sixth diode circuits 17 to 22, and this The lighting control is performed in units of groups of the divided first to sixth diode circuits 17 to 22. However, the present invention is not limited to this.

  For example, lighting control of a plurality of light emitting diodes 14 connected in series may be performed in units of each light emitting diode 14. In this case, a drive switch element is connected between each connection point between adjacent light emitting diodes 14 and the ground, and a predetermined drive switch of these drive switch elements is supplied with a pulsating voltage supplied from the rectifier circuit 13. By controlling on / off according to the instantaneous value, the number of lighting increases from the high potential side group to the ground side group in response to the change in the phase range where the pulsating voltage changes from a low value to a high value. In the phase range in which the pulsating voltage changes from a high value to a low value, the number of lightings decreases from the ground group to the high potential group in response to the change. The light emitting diode 14 may be controlled to be turned on.

  In this case, the drive switch element may be connected between the light emitting diode 14 at the final stage and the ground, or the light emitting diode 14 at the final stage may be directly connected to the ground. In short, it is only necessary that the drive switch element is connected between each connection point of the adjacent light emitting diodes 14 of the plurality of light emitting diodes 14 and the ground.

  (7) In the light emitting diode lighting device 10b according to the second embodiment, the light emitting diode circuit 64 includes three diode circuits (groups) of the first to third diode circuits 65 to 67. However, it is not limited to this. For example, it may be composed of two diode circuits (groups) or may be composed of four or more diode circuits (groups). In this case, the number of element drive circuits 83, 87, 91 constituting the element drive control circuit 75 is increased / decreased according to the number of diode circuits to be increased / decreased, and the element cutoff circuit 78 is corresponding to the increased / decreased element drive circuit. What is necessary is just to increase / decrease the number of the interruption | blocking switch elements 76 and 77 which comprise. Further, the number of light emitting diodes 63 connected in series is not limited to that of the embodiment, and may be appropriately set according to the number of diode circuits (groups), the rated value of the current that can be passed through the light emitting diodes 63, and the like. Can do.

  (8) In the light-emitting diode lighting device 10b according to the second embodiment, the first to third resistors constituting a constant current circuit between the first to third drive switch elements 69 to 71 and the ground. Although the elements 72 to 74 are inserted, the present invention is not limited to this. For example, a constant current circuit may be inserted between the high potential side of the rectifier circuit 62 and the light emitting diode circuit 64. In such a case, the first to third resistance elements 72 to 74 are not necessary.

  Therefore, in the present invention, regardless of the presence or absence of the first to third resistance elements 72 to 74, the first drive switch element 69 is connected to the connection point of the first diode circuit 66 and the second diode circuit 67. Between the ground, the second drive switch element 70 is connected between the connection point of the second diode circuit 67 and the third diode circuit 68 and the ground, and the third drive switch element 71 is connected to the third diode circuit 67. It is assumed that each is provided between the diode circuit 68 and the ground.

  (9) In the light emitting diode lighting device 10b according to the second embodiment, the third drive switch element 71 is provided between the light emitting diode 63 at the final stage of the third diode circuit 68 and the ground. However, it is not limited to this. For example, the third drive switch element 71 is not provided between the third diode circuit 68 and the ground, and the light-emitting diode 63 at the final stage of the third diode circuit 68 is directly connected to the ground. Good. Even if it does in this way, in addition to having the same effect, the number of parts can be reduced and the circuit configuration can be simplified. In short, at least a drive switch element is connected between each connection point of adjacent group units of a plurality of groups divided by a predetermined number of continuous light emitting diodes 63 among the plurality of light emitting diodes 63 and the ground. It only has to be.

  (10) In the light emitting diode lighting device 10b according to the second embodiment, the plurality of light emitting diodes 63 connected in series are divided into a plurality of groups of first to third diode circuits 65 to 67. Although lighting control is performed in units of groups of the divided first to third diode circuits 65 to 67, the present invention is not limited to this.

  For example, lighting control of a plurality of light emitting diodes 63 connected in series may be performed for each light emitting diode 63. In this case, the drive switch elements are connected between the connection points of the adjacent light emitting diodes 63 and the ground, and the instantaneous value (voltage value) of the pulsating voltage supplied from the rectifier circuit 62 to these drive switch elements. In accordance with the on / off control, in the phase range in which the pulsating voltage changes from a low value to a high value, the number of lightings from the high potential side light emitting diode 63 toward the ground side light emitting diode 63 corresponds to the change. In the phase range where the pulsating current voltage changes from a high value to a low value, the light emitting diode 63 is controlled to increase, and in response to the change, the light emitting diode 63 on the ground side is directed toward the light emitting diode 63 on the high potential side. The light emitting diode 63 may be controlled to be lit so that the number of lighting is reduced.

  In this case, the last stage light emitting diode 63 connected to the ground may be directly connected to the ground, or the drive switch element may be connected between the last stage light emitting diode 63 and the ground. Good. In short, it is only necessary that the drive switch element is connected at least between each connection point of the light emitting diodes 63 adjacent to each other and the ground.

  (11) In the light-emitting diode lighting device 10c according to the third embodiment, the light-emitting diode circuit 99 is configured by 18 light-emitting diodes 98, but is not limited thereto. The number of light emitting diodes 98 having a different driving voltage (specified voltage) from that of the embodiment can be used.

  (12) In the light-emitting diode lighting device 10c according to the third embodiment, the variable impedance circuit 100 includes the resistor circuit 101 including four resistor elements, the first to fourth resistor elements 109 to 112. However, it is not limited to this. For example, the number of resistance elements may be two or four or more, and the number of short-circuit switch elements may be increased or decreased according to the number of resistance elements. In short, as the number of resistance elements constituting the resistance circuit 101 increases, the impedance value (resistance value) of the variable impedance circuit 100 can be finely adjusted, and the current value flowing through the light emitting diode circuit 99 corresponding to the impedance value. Can be suppressed. A current limiting resistor can be further connected in series to the resistor circuit 101 of the variable impedance circuit 100.

  (13) In the light emitting diode lighting device 10c according to the third embodiment, the switch control unit 110 uses the counter 120 to count the instantaneous value of the pulsating voltage supplied from the rectifier circuit 97 (time). Although monitoring is performed, the present invention is not limited to this. For example, the instantaneous value of the pulsating voltage may be directly monitored by comparing the output from the voltage detection circuit 115 with a reference value by a comparison circuit.

  (14) In the light emitting diode lighting device 10c according to the third embodiment described above, the variable impedance circuit 100 is configured by discrete components, but is not limited thereto. For example, the resistor circuit 101, the first to third short-circuit switch elements 115 to 117, and the switch control circuit 118 can be configured as a variable impedance element integrated as a semiconductor integrated circuit or a hybrid integrated circuit.

  (15) In the light emitting diode lighting device 10d according to the fourth embodiment described above, the light emitting diode circuit 125 is configured by 18 light emitting diodes 124, but is not limited thereto. An appropriate number of light emitting diodes 124 having a driving voltage (specified voltage) different from that of the embodiment can be used.

  (16) In the light-emitting diode lighting device 10d according to the fourth embodiment, the variable impedance circuit 126 includes a resistor circuit 127 including four resistor elements, the first to fourth resistor elements 109 to 112. However, it is not limited to this. For example, the number of resistance elements may be at least two, and the number of drive switch elements may be increased or decreased according to the number of resistance elements. In short, as the number of resistance elements constituting the resistance circuit 127 increases, the impedance value (resistance value) of the variable impedance circuit 126 can be finely adjusted, and the current value flowing through the light emitting diode circuit 125 corresponding to the impedance value. It is possible to flatten by suppressing the change of.

  (17) In the light-emitting diode lighting device 10d according to the fourth embodiment, the fourth drive switch element 138 is provided between the fourth resistance element 134 and the ground. However, the present invention is not limited to this. is not. For example, the fourth resistance switch 134 may be directly connected to the ground without providing the fourth drive switch element 138 between the fourth resistance element 134 and the ground. Even if it does in this way, in addition to having the same operation effect, the number of parts can be reduced and the control operation can be simplified by eliminating the need for the control of the fourth drive switch element 138. . In short, it is only necessary that the drive switch element is connected at least between each connection point between the adjacent resistance elements and the ground.

  (18) In the light-emitting diode lighting device 10d according to the fourth embodiment, the variable impedance circuit 126 includes an element drive control circuit 140 that drives and controls the first to fourth drive switch elements 135 to 138; Although the switch control circuit 145 including the element cutoff circuit 144 configured to include the third cutoff switch elements 141 to 143 is provided, the present invention is not limited to this. For example, the first to fourth drive switch elements 135 to 138 may be drive-controlled (on / off control) by a switch control circuit including a microcomputer. In this case, the switch control circuit can have the same configuration as the switch control circuit 52 including the switch control unit 45, the voltage supply circuit 48, and the voltage detection circuit 51 in the first embodiment shown in FIG.

  (19) In the light emitting diode lighting device 10d according to the fourth embodiment described above, the variable impedance circuit 126 is configured by discrete components, but is not limited thereto. For example, a variable impedance in which a resistor circuit 127, first to fourth drive switch elements 135 to 138, first to third 141 to 143, an element drive control circuit 140, and the like are integrated as a semiconductor integrated circuit or a hybrid integrated circuit. It can also be configured as an element.

It is a figure which shows the circuit structure of the light emitting diode lighting device in the 1st Embodiment of this invention. It is a figure which shows the waveform of the pulsating voltage in the light emitting diode lighting device of FIG. It is a time chart for demonstrating operation | movement of the lighting control circuit in the light emitting diode lighting device of FIG. It is a figure which shows the circuit structure of the light emitting diode lighting device in the 2nd Embodiment of this invention. It is a time chart for demonstrating operation | movement of the lighting control circuit in the light emitting diode lighting device of FIG. It is a figure which shows the circuit structure of the light emitting diode lighting device in the 3rd Embodiment of this invention. It is a time chart for demonstrating operation | movement of the variable impedance circuit in the light emitting diode lighting device of FIG. It is a figure which shows the circuit structure of the light emitting diode lighting device in the 4th Embodiment of this invention. It is a time chart for demonstrating operation | movement of the variable impedance circuit in the light emitting diode lighting device of FIG. It is a figure which shows the circuit structure of the light emitting diode lighting device of a prior art example. It is a wave form diagram of a pulsating voltage for explaining the operation range in the light emitting diode lighting device of the conventional example. It is a figure which shows the circuit structure of another light emitting diode lighting device of a prior art example. It is a figure which shows the circuit structure of another light emitting diode lighting device of a prior art example.

Explanation of symbols

10a, 10b, 10c, 10d Light emitting diode lighting device 14, 63, 98, 124 Light emitting diode 13, 62, 97, 123 Rectifier circuit 17, 65 Lighting control circuit 30, 31, 32, 33, 34, 35, 69, 70 , 71, 135, 136, 137, 138 Drive switch element 76, 77, 141, 142, 143 Cutoff switch element 52, 79, 117, 145 Switch control circuit 75, 140 Element drive control circuit 78, 144 Element cutoff circuit 83, 87, 91, 150, 154, 158, 162 Element driving circuit 100, 126 Variable impedance circuit 101, 127 Resistance circuit 103, 104, 105, 106, 131, 132, 133, 134 Resistance element

Claims (9)

  A light-emitting diode lighting device for lighting a plurality of light-emitting diodes connected in series, a rectifier circuit for supplying a pulsating voltage obtained by rectifying an AC voltage to a series-connected circuit of the plurality of light-emitting diodes, and the rectifier circuit In the phase range in which the pulsating voltage supplied from the low value changes to a high value, the light emitting diodes are controlled so that the number of lightings increases corresponding to the change, and the pulsating voltage is reduced from a high value to a low value. A light-emitting diode lighting device comprising: a lighting control circuit that controls lighting of the light-emitting diodes so that the number of lighting is reduced in response to the change in the phase range that changes.   The lighting control circuit includes a plurality of drive switch elements connected between a predetermined connection point and a ground among a plurality of connection points between adjacent light emitting diodes of the plurality of light emitting diodes, and the pulsating voltage is low. In the phase range in which the value changes from a high value to a high value, the plurality of drive switches so that the number of lights increases from the light emitting diode on the high potential side toward the light emitting diode on the ground side among the plurality of light emitting diodes in response to the change. In a phase range in which a predetermined drive switch element is turned on among the elements and the pulsating voltage changes from a high value to a low value, the light emitting diode on the ground side from the light emitting diode on the ground side among the plurality of light emitting diodes corresponds to the change. Among the plurality of drive switch elements, a switch that turns on a predetermined drive switch element so as to reduce the number of lights toward the light emitting diode. Light emitting diode lighting device according to claim 1, characterized in that a switch control circuit.   The switch control circuit is configured to include a microcomputer including a clock oscillation circuit, and the number of clocks generated by the clock oscillation circuit and the instantaneous value of the pulsating voltage are set to a zero potential of the pulsating voltage. If the number of clocks is in a phase range in which the pulsating voltage changes from a low value to a high value, the high-potential side of the plurality of light emitting diodes corresponding to the number of clocks. A predetermined drive switch element is turned on among the plurality of drive switch elements so that the number of lights increases from the light emitting diode toward the ground side light emitting diode, and the clock number is changed from a high value to a low value of the pulsating voltage. If the phase is in the changing phase range, the light emitting diode on the high potential side from the light emitting diode on the ground side among the plurality of light emitting diodes corresponds to the number of clocks. Light emitting diode lighting device according to claim 2, characterized in that to turn on the predetermined driving switch element of the plurality of drive switching elements to the lighting number toward the diode is reduced. Said switch control circuit, said pulsating voltage a plurality of element driving circuit the rectifier circuit instantaneous value turns on the corresponding drive switch of the plurality of drive switches by being in the driving state exceeds a predetermined value The element drive control circuit configured to be connected in parallel with each other, and the element drive control between each control terminal of the drive switch element connected between the connection point of the light emitting diodes and the ground and the ground It is configured by connecting cutoff switch elements that are driven and controlled by a circuit, and when a predetermined drive switch element is turned on among the plurality of drive switch elements, the switch is turned on at a higher potential side than the drive switch element. In the phase range where the pulsating voltage changes from a low value to a high value. Correspondingly, a predetermined drive switch element among the plurality of drive switch elements is turned on so that the number of lighting is increased from the light emitting diode on the high potential side to the light emitting diode on the ground side among the plurality of light emitting diodes, In the phase range where the pulsating voltage changes from a high value to a low value, the number of lighting is reduced from the light emitting diode on the ground side to the light emitting diode on the high potential side among the plurality of light emitting diodes in response to the change. The light emitting diode lighting device according to claim 2, wherein a predetermined drive switch element is turned on among the plurality of drive switch elements.   A light-emitting diode lighting device that lights a plurality of light-emitting diodes connected in series, the rectifying circuit supplying a pulsating voltage obtained by rectifying an AC voltage to the series connection circuit of the light-emitting diodes, and the series connection Are connected in series to a plurality of light emitting diodes, and the impedance value is varied corresponding to the instantaneous value of the pulsating voltage, and in the phase range where the pulsating voltage changes from a low value to a high value, the change occurs. Correspondingly, the impedance value is sequentially increased, and in the phase range in which the pulsating voltage changes from a high value to a low value, the variable impedance circuit is configured to sequentially reduce the impedance value corresponding to the change. A light emitting diode lighting device.   The variable impedance circuit includes a plurality of resistance elements connected in series, a resistance circuit connected in series to the plurality of light emitting diodes, and a plurality of resistance elements connected to both ends of the resistance element of the resistance circuit and short-circuiting the resistance elements In the phase range in which the pulsating voltage changes from a low value to a high value, the short-circuit switch element is turned from on to off so that the resistance value of the resistance circuit increases in response to the change. In the phase range in which the pulsating voltage changes from a high value to a low value, the short-circuit switch element is turned from OFF to ON so that the resistance value of the resistor circuit decreases in response to the change. The light emitting diode lighting device according to claim 5, further comprising a switch control circuit that sequentially reduces the impedance value.   The switch control circuit is configured to include a microcomputer including a clock oscillation circuit, and the number of clocks generated by the clock oscillation circuit and the instantaneous value of the pulsating voltage are set to a zero potential of the pulsating voltage. When the number of clocks is in a phase range in which the pulsating current voltage changes from a low value to a high value, the resistance value of the resistor circuit increases corresponding to the number of clocks. The impedance value is sequentially increased by turning off the short-circuit switch element, and the resistance of the resistor circuit corresponds to the change in the phase range in which the number of clocks changes from a high value to a low value of the pulsating voltage. The impedance value is sequentially decreased by turning the short-circuit switch element from OFF to ON so that the value decreases. Diode lighting device.   The variable impedance circuit includes a plurality of resistance elements connected in series, a resistance circuit connected in series to the plurality of light emitting diodes, a connection point between adjacent resistance elements of the plurality of resistance elements, and a ground. A plurality of drive switch elements connected in between, and in the phase range in which the pulsating voltage changes from a low value to a high value, the plurality of drive switches so that the resistance value of the resistor circuit increases corresponding to the change The impedance value is sequentially increased by turning on a predetermined drive switch of the elements, and the resistance value of the resistance circuit decreases corresponding to the change in the phase range where the pulsating voltage changes from a high value to a low value. And a switch control circuit that sequentially decreases the impedance value by turning on a predetermined drive switch among the plurality of drive switch elements. Light emitting diode lighting device according to claim 5, characterized. Said switch control circuit, said pulsating voltage a plurality of element driving circuit the rectifier circuit instantaneous value turns on the corresponding drive switch of the plurality of drive switches by being in the driving state exceeds a predetermined value The element drive control circuit configured to be connected in parallel to each other, and the element drive control between each control terminal of the drive switch element connected between the connection point of the resistance elements and the ground and the ground A drive switch that is connected to a cutoff switch element that is driven and controlled by a circuit, and that is turned on at a higher potential side than the drive switch element when a predetermined drive switch element is turned on among the plurality of drive switch elements An element cutoff circuit that turns off the element when the cutoff switch element is turned on, and the pulsating voltage changes from a low value to a high value. In the phase range, in response to the change, the connection number of the plurality of drive switch elements is increased so that the number of connection of the resistance elements increases from the high-potential-side resistance elements to the ground-side resistance elements. The impedance value is sequentially increased by turning on a predetermined drive switch element, and in the phase range in which the pulsating voltage changes from a high value to a low value, the ground side of the plurality of resistance elements corresponds to the change. The impedance value is sequentially decreased by turning on a predetermined drive switch element among the plurality of drive switch elements so that the number of connected resistance elements decreases from the first resistance element toward the high potential side resistance element. 9. The light emitting diode lighting device according to claim 8, wherein the device is a light emitting diode lighting device.

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