WO2013000410A1 - Light emitting diode(led) driving device - Google Patents

Abstract

A Light Emitting Diode(LED) driving device, comprising: a light attenuation regulator module(3), for generating and outputting light attenuation compensation signal which is monotonously changed in a default rate with lighting time increasing according to the attenuation level of the luminous intensity of an LED light source with lighting time increasing; an LED driver(1), which is connected between a power supply and the LED light source, and with a dimming line(2) reserved. The LED driver(1) is connected to the light attenuation regulator module(3) through the dimming line(2), and is controlled by the light attenuation compensation signal on the dimming line(2) so that its output current increases with lighting time increasing. Using the technical solution, the light attenuation compensation signal which is the output from the LED driver(1) with the dimming line(2) to the dimming line(2) by the light attenuation regulator module(3), is controlled by the dimming line(2) to output current increasing with the accumulative lighting time of the LED light source increasing, thus the luminous flux output by the LED light source is increased with the accumulative lighting time of the LED light source increasing and light attenuation compensation is carried out. The solution does not need to reserve current during driving LED light sources, and then resources are saved.

Description

 The present invention claims priority to Chinese Patent Application No. 201120220675.9, entitled "A LED Driver", filed on June 27, 2011, the entire contents of which is hereby incorporated by reference. in.

Technical field

 The present invention relates to the field of LED device technology, and more particularly to an LED driving device. Background technique

 At present, LED (Light Emitting Diode) light source has been widely used in the field of illumination because it does not contain toxic substances, environmental protection, long life and high photoelectric efficiency. The LED source is powered by a constant current source as a driver. Although the LED light source is driven by a constant current source, the luminous flux output from the LED light source decreases with time due to the aging effect of the chip and the phosphor, that is, the luminous flux of the LED light source is gradually attenuated. Summary of the invention

 In view of the above, the present invention provides an LED driving device that outputs a current that gradually increases with the attenuation of the LED light source, and drives the LED light source to ensure that the luminous flux output by the LED light source can always satisfy the illumination of the illuminated area as the cumulative illumination time increases. Requirements, thereby saving resources. The technical solution is as follows:

 The invention provides an LED driving device for an LED, comprising:

For the degree of attenuation of the luminous intensity of the LED light source as the illumination time increases, resulting in And outputting a light attenuation adjustment module of the light attenuation compensation signal that monotonously changes at a preset rate as the illumination time increases;

 Connected between the power supply and the LED light source, and a light-adjusting LED driver is reserved, and the LED driver is connected to the light decay adjustment module through the light modulation, and is controlled by the light attenuation compensation signal on the modulated light The LED driver output current increases as the illumination time increases.

 Preferably, the light decay adjustment module is provided with a light attenuation adjustment line for adjusting a preset rate of the light decay adjustment signal generated by the light decay adjustment module.

 Preferably, the light attenuation adjustment line is externally connected to a voltage signal or an external resistor;

 When the voltage signal is externally connected, the level value on the light attenuation adjustment line is equal to the amplitude of the external voltage signal;

 When an external resistor is connected, the external resistor is connected between the reference source of the light attenuation adjusting circuit and the voltage dividing resistor, and the level value on the light decay adjusting line is equal to the external resistor and the voltage dividing resistor pair The partial pressure value of the reference source.

 Preferably, the light failure adjustment module comprises: a discharge battery;

 a first resistor and a second resistor connected in series across the discharge battery;

 The emitter is connected to the reference source, the collector is grounded through the third resistor, the base is connected to the PNP transistor of the first resistor and the second resistor connection point through the fourth resistor, the collector of the PNP transistor and the third resistor The connection point is connected to the dimming light.

 Preferably, the light failure adjustment module comprises: a discharge battery;

 a fifth resistor connected across the discharge battery;

 An impedance matching circuit connected between the discharge current output of the discharge battery and the modulating light.

Preferably, the light attenuation adjustment module comprises a timing output unit and a light attenuation adjustment output unit: The timing output unit is configured to cycle timing, and triggers the light decay adjustment output unit every time the timing time T expires;

 The light attenuation adjustment output unit is configured to generate and output a light attenuation compensation signal that monotonously changes at a preset rate as the illumination time increases, and the light attenuation adjustment output unit currently outputs the light attenuation compensation signal relative to the previous output The increase or decrease value of the light decay compensation signal is the product of the preset rate a and the timing time T.

 Preferably, the method further includes: a dimming module connected to the LED driver by the dimming light, the dimming module is configured to output a dimming signal to the dimming light, and the optical attenuation compensation signal on the dimming light The output current of the LED driver is adjusted together with the dimming signal.

 Preferably, the dimming module comprises a timing unit and a dimming output unit:

 A timing unit for segment timing, and triggering the dimming output unit to output a dimming signal every time the timing time expires.

 Connected to the dimming light, output dimming output units of different dimming signals according to different triggered moments.

 Preferably, the method further includes a control signal applied to the input end of the light attenuation adjustment module, the light attenuation adjustment module superimposing the control signal on the light attenuation compensation signal, and the light attenuation compensation signal superimposed with the control signal The output is output to the dimming light, and the LED driver output current is controlled by the optical attenuation compensation signal superimposed with the control signal on the dimming light.

 Preferably, the control signal is any one or more of a temperature compensation signal, an infrared switch signal, and a dimming signal.

Preferably, the light attenuation adjustment module includes: a level conversion circuit having an input terminal connected to the control signal, a filter, and a microcontroller MCU linked between the level conversion circuit and the filter; among them:

 The level conversion circuit is configured to convert the control signal into a control signal that meets a range of effective sizes of the MCU input end;

 The MCU is configured to convert the control signal converted by the level conversion circuit and the light attenuation compensation signal generated by itself into dimming data, and convert the dimming data into a PWM signal and output the signal to the filter;

 The filter performs filtering processing on the PWM signal, and outputs a light attenuation compensation signal superimposed with the control signal to the LED driver, and the control signal is converted by the level conversion circuit.

 Preferably, the level shifting circuit comprises: a sixth resistor and a seventh resistor connected in series between the control signal and the ground, wherein a connection point of the sixth resistor and the seventh resistor is connected to the MCU Input.

 Preferably, the filter includes: an eighth resistor connected between the dimming light and an output end of the MCU;

 One end is connected to the connection point of the eighth resistor and the output end of the MCU, and the other end is grounded. Preferably, the light attenuation adjustment module is connected to the modulating light through a signal conversion module, and the signal conversion module is configured to convert the light fading compensation signal output by the light fading adjustment module into an effective size range on the modulating light. The standard light decay compensation signal is output to the modulated light, and the LED driver output current is controlled by the standard light decay compensation signal on the modulated light.

 Preferably, the LED driver and the light attenuation adjustment module are separately packaged.

Applying the above technical solution, the LED driver with the modulating light is outputted by the light fading adjustment module to the light fading compensation signal on the modulating light, and the output current of the modulating light is increased as the cumulative illumination time of the LED light source increases, thereby realizing Increase the LED light source output with the cumulative illumination time of the LED light source Luminous flux, to achieve light attenuation compensation, so as to ensure that the luminous flux output by the LED light source can increase the illuminance of the illuminated area with time. Compared with the prior art, when driving the LED light source, there is no need to reserve current, thereby saving resources. DRAWINGS

 In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description It is merely some embodiments of the present invention, and those skilled in the art can obtain other drawings according to these drawings without any creative work.

 1 is a schematic structural diagram of an LED driving device according to an embodiment of the present invention;

 FIG. 2 is a schematic diagram of another structure of an LED driving device according to an embodiment of the present invention; FIG. 3 is a schematic structural diagram of an LED driving device according to an embodiment of the present invention; FIG. FIG. 5 is a schematic structural view of an LED driving device according to an embodiment of the present invention; FIG. 6 is a schematic structural view of another embodiment of the LED driving device according to an embodiment of the present invention; FIG. 8 is a schematic diagram of another embodiment of the LED driving device provided in the embodiment; FIG.

 FIG. 9 is a schematic structural diagram of still another embodiment of an LED driving device according to an embodiment of the present invention; FIG. 10 is a schematic diagram of current variation of FIG.

FIG. 11 is a schematic structural diagram of still another embodiment of an LED driving device according to an embodiment of the present invention. detailed description The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

 One embodiment

 Referring to FIG. 1, FIG. 1 is a schematic structural diagram of an LED driving device according to an embodiment of the present invention, including: an LED driver 1, a dimming light 2, and a light decay adjusting module 3. among them:

 The light decay adjustment module 3 is configured to generate and output a light attenuation compensation signal that monotonously changes at a preset rate as the illumination time increases in accordance with the degree to which the illumination intensity of the LED light source decreases with increasing illumination time.

 The LED driver 1 is connected between the power supply and the LED light source to supply current to the LED light source. The LED driver 1 is reserved for dimming light 2, and the dimming light 2 is connected to the light decay adjustment module 3. The supply current outputted by the LED driver 1 to the LED light source changes as the signal on the dimming light 2 changes, that is, the output current is controlled by the light decay compensation signal on the dimming light 2 to increase with the illumination time to ensure the LED The luminous flux output by the light source can increase the requirement to meet the illumination of the illuminated area over time. For example, when the output current of the LED driver 1 increases as the signal on the dimming light 2 increases, the optical attenuation compensation signal generated by the optical attenuation adjustment module 3 increases as the illumination time increases, then the LED driver 1 The output current increases as the illumination time increases. On the contrary, when the output current of the LED driver 1 increases as the signal on the dimming light 2 decreases, the optical attenuation compensation signal generated by the optical attenuation adjustment module 3 decreases as the illumination time increases, and likewise, the LED driver 1 The output current will increase as the illumination time increases.

The light decay compensation signal generated by the light decay adjustment module 3 is as close as possible to the light decay rate of the LED light source with a preset rate of illumination time. As shown in FIG. 2, when the light attenuation adjustment line 0 is disposed on the light attenuation adjustment module 3, the preset rate can be adjusted according to the level value on the light attenuation adjustment line 0. Light decay The adjusting line 0 determines the level value by an external voltage signal or an external resistor: when the voltage signal is externally connected, the level value on the light decay adjusting line 0 is equal to the amplitude of the external voltage signal; when the external resistor is connected, the external resistor Connected between the reference source of the light decay adjustment circuit and the voltage dividing resistor, the light attenuation adjustment line 0 is connected to the connection point of the external resistor and the voltage dividing resistor, and the level value on the light attenuation adjustment line 0 The voltage divider value of the external resistor and the divider resistor to the reference source.

 The light decay adjustment line 0 determines the preset rate according to the connected level value, thereby adjusting the output light attenuation compensation signal. For example, if the level value Vn connected to the light attenuation adjustment line 0 is Vnl ≤ Vn ≤ Vml, the adjustment rate is al; if the level value Vn connected to the light attenuation adjustment line 0 is Vn2 ≤ Vn ≤ Vm2, then The adjustment rate is a2; if the level value Vn connected to the light attenuation adjustment line 0 is Vnx ≤ Vn ≤ Vmx, the adjustment rate is a3. That is, the level of the light attenuation adjustment line 0 is different, and the preset rate is different. When the light fade line 0 is left floating, that is, when the level is not connected, the light fade adjustment module 3 adjusts the output light fade compensation signal according to the preset rate set by itself.

For LED light sources with different light decay rates, different sized level values can be selected to determine different preset rates. For example, for an LED light source with a large light decay rate, the light fade adjustment line 0 can select a larger level value to obtain a larger preset rate, which is the light decay compensation rate. For example, there are two kinds of LED light sources, the light decay rates are bl and b2, respectively, and bl < b2. For an LED light source with a light decay rate of bl, select a level within the size range of [Vnl, Vml], and the light decay adjustment module. 3, according to the level value, the preset rate is determined as al; for the LED light source with the light decay rate of b2, select a level within the range of [Vn ² , Vm ² ], and the light attenuation adjustment module 3 can be This level determines that the preset rate is a2, where a2 > al.

When the LED driving device simultaneously controls the LED load composed of the LED light sources of the above two different light decay rates, the light decay adjustment line 0 is connected to a level within the size range of [Vn2, Vm2], and the light decay adjustment circuit 3 is detected according to The light fades the level on line 0 to determine the preset rate as a2. Because the preset rate a2 is greater than the preset rate al, that is, when the LED load contains two or more different light decay rates At the rate of the LED source, the preset rate (ie, the rate of light decay compensation) should be determined based on the maximum rate of light decay. Therefore, the LED driving device can play the role of light attenuation compensation for LED light sources with different light decay rates.

It should be noted that: the light decay rate is used to indicate the degree of light attenuation of the LED light source in a certain period of time, and the preset rate, that is, the light decay compensation rate, is used to indicate the degree of light attenuation compensation of the LED driving device in a certain period of time. The light decay compensation rate is the growth rate of the LED driver output current to compensate the light decay rate of the selected LED light source, so that the LED light source can meet the user's optical parameters such as luminous flux and illumination at any illumination time. The light decay compensation rate is expressed as the amount of current increase in a fixed time, and is expressed as ^{β = Δ} / ^Δί . Where a is the rate of light decay compensation, Δ Ι is the amount of increase in the output current of the LED driver, and A t is a fixed time.

 The light decay adjustment module 3 includes a discharge battery 31, a first resistor 32, a second resistor 33, a PNP type transistor 34, a third resistor 35, a fourth resistor 36, and a reference source 37. See FIG. 3 for a circuit diagram. among them:

 The first resistor 32 and the second resistor 33 are connected in series across the discharge battery 31. The emitter of the PNP type transistor 34 is connected to the reference source 37, the collector is grounded through the third resistor 35, and the base is connected to the junction point of the first resistor 32 and the second resistor 33 through the fourth resistor 36. The collector of the PNP type transistor 34 and the connection point of the third resistor 35 are connected to the light 2 for outputting the light decay compensation signal generated by the light decay adjustment module 3 to the modulated light 2.

 In the LED driving device shown in Fig. 3, the LED driver 1 includes an LED driving circuit 11, a current regulating circuit 12, and a driving control circuit 13. Among them: LED drive circuit 11 is connected between the power supply and the LED light source, and outputs current to the LED light source.

The current adjustment circuit 12 is configured to compare and adjust the light decay compensation signal (ie, the output signal of the light decay adjustment module) on the modulated light 2 and the current signal outputted from the output of the LED drive circuit 11, and output a comparison adjustment result. The current adjustment circuit 12 includes: a sixth resistor 121, a seventh resistor 122, a compensation network 123, The first operational amplifier 124, the reference signal 125, and the eighth resistor 126. The non-inverting input terminal of the first operational amplifier 124 is connected to the dimming light 2 through the sixth resistor 121, and the inverting input terminal samples the output current of the LED driving circuit 11 through the seventh resistor 122, and the output terminal passes through the compensation network 123 and the inverting input. Connected to the end. The output of the first operational amplifier 124 is connected to the drive control circuit 13.

 The reference signal 125 is coupled through an eighth resistor 126 to the junction of the non-inverting input of the first operational amplifier 124 and the sixth resistor 121. The reference signal 125 is used to enable the LED driver to operate normally when the dimming light 2 is left floating.

 The driving control circuit 13 is configured to generate a pulse signal according to the comparison adjustment result output by the current adjustment circuit 12, and control the on/off of the switching tube in the LED driving circuit 11 to control the output current of the LED driving circuit 11 to drive the LED light source to ensure the output of the LED light source. The luminous flux can increase the requirement to meet the illumination of the illuminated area over time.

 The working principle of the LED driving device shown in FIG. 3 is as follows: the LED light source has a light decay as the illumination time increases, that is, although the current of the LED light source does not change, the luminous flux decreases as the illumination time increases; likewise, the discharge As the discharge time of the battery 31 increases, the voltage at the connection point of the first resistor 32 and the second resistor 33 decreases. The base current of the PNP type transistor 34 increases, the on-resistance becomes small, and the voltage drop of the third resistor 35 increases, that is, the light decay compensation signal output to the dimming light 2 increases. At this time, the voltage of the non-inverting input terminal of the first operational amplifier 124 is increased, and the closed loop is adjusted, that is, the first operational amplifier 124 outputs a comparison result of the voltage value of the non-inverting input terminal greater than the voltage value of the inverting input terminal to the driving control circuit 13 . Controlling the switching of the switching transistor in the LED driving circuit 11, increasing the output current of the LED driving circuit 11, that is, increasing the current at the sampling point 1, to ensure that the voltages of the non-inverting input terminal and the inverting input terminal of the first operational amplifier 124 are equal. .

The current adjustment circuit 12 and the light attenuation adjustment circuit 3 described above may also employ a circuit diagram in the LED drive device shown in FIG. The light decay adjustment module 3 of FIG. 4 includes: a discharge battery 38, a fifth resistor 39, and an impedance matching circuit 40. Wherein: the fifth resistor 39 is connected to both ends of the discharge battery 38. Impedance matching The circuit 40 is connected between the current output terminal of the discharge battery 38 and the dimming light 2 for ensuring that the discharge battery 38 can only be discharged through the fifth resistor 39.

 The current regulating circuit 12 includes: a reference signal 127, a ninth resistor 128, a compensation network 129, a second operational amplifier 130, and a tenth resistor 131. The non-inverting input of the second operational amplifier 130 is connected to the reference signal 127, the inverting input is sampled by the ninth resistor 128, and the output terminal is connected to the inverting input through the compensation network 129. The output terminal of the second operational amplifier 130 is connected to the drive control circuit 13, and the connection point between the inverting input terminal and the ninth resistor 128 is connected to the output of the impedance matching circuit 40, that is, the optical attenuation adjustment circuit 3, through the tens resistor 131.

 The working principle of the LED driving device shown in FIG. 4 is as follows: the LED light source has a light decay as the illumination time increases, that is, although the current of the LED light source does not change, the luminous flux decreases as the illumination time increases; likewise, the discharge As the discharge time of the battery 31 increases, the voltage at the input of the impedance matching circuit 40 becomes smaller and smaller. The inverting input terminal voltage of the second operational amplifier 130 is a divided voltage value after the voltage difference between the voltage at the sampling point 2 and the output voltage of the impedance matching circuit 40 is divided by the ninth resistor 128 and the tenth resistor 131.

 When the illumination time increases, the voltage at the input end of the impedance matching circuit 40 becomes smaller and smaller, and the voltage of the inverting input terminal of the second operational amplifier 130 is closed-loop adjusted, that is, the voltage output from the non-inverting input terminal of the first operational amplifier 124 is greater than the inverse The comparison result of the voltage value of the phase input terminal is adjusted to the drive control circuit 13, which controls the on/off of the switch tube in the LED drive circuit 11, increases the output current of the LED drive circuit 11, that is, increases the voltage at the sampling point 2, to ensure the first The non-inverting input of an operational amplifier 124 is equal to the voltage of the inverting input.

The sampling point 1 in FIG. 4 is specifically that a resistor R is connected between the output end of the LED driving circuit 11 and the cathode of the LED light source, and one end of the resistor R connected to the output end of the LED driving circuit is used as a reference ground, and the other end of the resistor R is connected. The ninth resistor 128, the voltage at the sampling point 2 is approximately the product of the output current of the LED driving circuit 11 and the resistance R. The discharge battery in FIG. 3 and FIG. 4 can be selected as a button battery, and the discharge rate of the discharge battery should be adjusted as much as possible to the light decay rate of the LED, and the increase of the current can make the luminous flux outputted by the LED light source increase with time to satisfy the illuminated area. Illumination requirements.

 The light attenuation adjustment module 3 and the current adjustment circuit 12 in the above Figs. 3 and 4 can be combined with each other, and the same current can be outputted so that the luminous flux of the LED light source satisfies the illumination requirement of the illuminated area, which will not be described. The compensation network in Figure 3 or Figure 4 can be a series connection of resistors and capacitors. It can also be a series capacitor and resistor, and then connect the capacitor and resistor in series with another capacitor.

 The light fade adjustment circuit 3 can also adopt a timing adjustment manner, as shown in FIG. 5, including: a timing output unit 41 and a light fade adjustment output unit 42. The timing output unit 41 is for cycle timing, and triggers the light fade adjustment output unit 42 every time the timing time T expires. The light fade adjustment output unit 42 is configured to generate and output a light decay compensation signal that monotonously changes at a preset rate as the illumination time increases. The light decay adjustment output unit 42 increases or decreases the light decay compensation signal currently output relative to the last output light attenuation compensation signal by the product of the preset rate a and the timing time T.

 The LED driver of Figure 5 can be either of Figure 3 or Figure 4 and will not be described again.

If the effective range of the signal on the dimming light 2 of the LED driving device shown in FIG. 1 to FIG. 5 is 0-10V, when the optical attenuation compensation signal outputted by the optical attenuation adjusting module 3 does not satisfy the requirement, it needs to be Make the conversion. A signal conversion module can be added to any of the LED driving devices shown in FIGS. 1 to 5, as shown in FIG. Fig. 6 is a schematic view showing still another structure of the LED driving device, based on Fig. 1. The signal conversion module 4 is connected between the light attenuation adjustment module 3 and the dimming light 2, and is configured to convert the optical attenuation compensation signal outputted by the optical attenuation adjustment module 3 into a standard optical attenuation compensation signal output within an effective size range of the modulated light. To the dimming light 2, the standard light decay compensation signal on the dimming light 2 controls the output current of the LED driver 1, that is, the standard light decay compensation signal on the dimming light 2 controls the output current of the LED driver 1 to increase as the illumination time increases. . The conversion of the signal by the signal conversion module 4 is specifically: if the amplitude of the light attenuation compensation signal output by the light attenuation adjustment module 3 is 2.5V, and the amplitude of the light attenuation compensation signal output by the light attenuation adjustment module 3 is 0-5V, then It is necessary to convert the light decay compensation signal to the effective amplitude range of the dimming light 2, that is, 0-10V. The signal conversion module 4 is amplified according to the amplitude ratio, here is an amplification according to 1/2 to 5V output. If the amplitude of the light attenuation compensation signal output by the light attenuation adjustment module 3 is 12.5V, and the amplitude of the light attenuation compensation signal output by the light attenuation adjustment module 3 is 0-20V, the signal conversion module 4 performs the light attenuation compensation signal according to the amplitude. The value scale is reduced, here it is reduced to 6.25V output by 1/2.

 Applying the above technical solution, the LED driver 1 with dimming light is outputted by the light decay adjustment module 3 to the light decay compensation signal on the dimming light 2, and the output current of the dimming control is increased as the cumulative illumination time of the LED light source increases. Furthermore, the luminous flux outputted by the LED light source is increased with the cumulative illumination time of the LED light source, and the light attenuation compensation is realized, thereby ensuring that the luminous flux output by the LED light source can increase the illumination requirement of the illuminated area with time. Compared with the prior art, when driving the LED light source, there is no need to reserve current, thereby saving resources. Another embodiment

 The above embodiment illustrates how the dimming light 2 controls the output current of the light according to the light decay compensation signal output by the light decay adjustment module. In practical applications, in addition to the control of the LED light source compensation, it is also necessary to control the brightness of the LED light source. Fig. 7 is a schematic view showing still another structure of the LED driving device according to the embodiment of the present invention, and at the same time, the light attenuation compensation and dimming control of the LED light source are realized. Fig. 7 shows the addition of the dimming module 5 to the LED driving device shown in Fig. 1. among them:

 The dimming module 5 is connected to the LED driver 1 through the dimming light 2 for outputting the dimming signal to the dimming light 2. The light attenuation compensation signal outputted by the light attenuation adjustment circuit 3 on the light 2 and the dimming signal output from the dimming module 5 control the output current of the LED driver 1, and simultaneously realize the light decay compensation and dimming function.

Fig. 8 is a schematic diagram showing current changes based on the LED driving device shown in Fig. 7. Can be seen from the picture The light decay compensation of the light decay adjustment circuit 3, during 0 < t < tl, tl < t < t2, t > t2, the driving current of the LED light source slowly increases with time (in the figure In order to facilitate the illustration of the effect of the light decay adjustment module on the LED light source drive current, the current growth rate is increased; when the user dims it at time tl, the drive current of the LED light source is rapidly reduced from 12 to II; When t2 is brightened, the LED light source compensates for the light decay from time t1 to t2, and the current has slowly increased from II to 13, and the brightening action rapidly increases the current from 13 to 14.

 The dimming module 5 and the optical fading adjustment circuit 3 described above may be packaged separately or in combination. The dimming module 5 can adopt timing dimming. FIG. 9 is a schematic structural diagram of another embodiment of the LED driving device according to the embodiment of the present invention.

 The dimming module 5 includes: a timing unit 51 and a dimming output unit 52. among them:

 The timing unit 51 is used for segment timing, and triggers the dimming output unit 52 to output a dimming signal every time the timing time expires. After receiving the trigger signal, the dimming output unit 52 outputs different dimming signals to the dimming light 2 connected thereto according to the different times at which it is triggered.

 For example, the timing unit 51 triggers the dimming output unit 52 from the late 12 o'clock time of the previous day to 6 o'clock the next morning. At this time, the dimming output unit 52 outputs the dimming signal to turn off the LED light source; then, the timing is up to 5 o'clock in the evening, and the dimming output unit 52 is triggered again. At this time, the dimming output unit 52 outputs a dimming signal to make the LED light source have a certain brightness; when it is 12 o'clock in the evening, the dimming output unit 52 is triggered again. At this time, the dimming output unit 52 outputs a dimming signal to darken the LED lamp.

The light fade adjustment module 3 includes: a timing output unit 43 and a light fade adjustment output unit 44. The timing output unit 43 is used for segmentation timing, and triggers the light fade adjustment output unit to output a light fade compensation signal every time the timing time expires. The light fade adjustment output unit 44 is connected to the modulating light 2 for outputting and outputting a light fading compensation signal monotonously varying at a preset rate as the illumination time increases. The light decay compensation signal currently outputted by the light fade adjustment output unit 44 is increased or decreased with respect to the last output light fade compensation signal by a product of a preset rate a and a timing time T. Referring to FIG. 10, FIG. 10 is a schematic diagram of current variation based on FIG. 9, wherein waveform 1 is a current waveform of dimming the LED light source when the dimming module 5 is separately applied to the dimming light 2, and the waveform 2 is the optical attenuation adjusting module 3 separately. A current waveform for performing light attenuation compensation on the LED light source when the light is adjusted 2, and a waveform 3 is a current waveform when both the dimming module 5 and the light decay adjustment module 3 act on the light adjustment 2, and the current at a certain time in the waveform 3 The mutation is caused by timing dimming, and the slow increase of current during a certain period of time is caused by the compensation of light decay. As can be seen from the figure, when the dimming signal outputted by the dimming module 5 acts on the dimming light, the LED driver output current increases or decreases as the dimming signal changes. When the light decay compensation signal outputted by the light decay adjustment module 3 acts on the modulated light 2, the LED driver output current is always increased.

 It should be noted that waveform 2 is for increasing the influence of the light attenuation adjustment module 3 on the current of the LED light source, and the current growth rate is increased. In practice, the light attenuation compensation is very slow; in waveform 1, when 0 < t < tl It means that the lighting demand is small during the time between midday and dawn, and the LED light source is illuminated with a certain brightness of 1=11. When t1 < t < t2, it means the daytime of the day, the light source is off 1=0, when t2 < t < When t3 indicates that the lighting demand is large after the night of the day, the LED light source is illuminated with a certain brightness of 1=12, 12>11.

 The LED driver 1 in the above LED driving device can adopt the structure in Fig. 3 or Fig. 4, which will not be described again. Of course, the signal conversion module 4 in Fig. 5 can also be added.

 Applying the above technical solution, the dimming control of the LED light source is realized while realizing the compensation of the light source of the LED light source. Still another embodiment

Referring to FIG. 11, FIG. 11 is a schematic structural diagram of still another LED driving device according to an embodiment of the present invention. Based on the LED driving device shown in FIG. 1, a control signal applied to the input end of the light attenuation adjusting module 3 is added. The light fade adjustment module 3 will control the input signal and its own light attenuation compensation signal. After superimposing, a superimposed signal is output to the dimming light 2, that is, the signal on the dimming light is a photo-compensation signal superimposed with the control signal, and finally the current output by the LED driver is changed with the optical decay compensation signal superimposed with the control signal. The change, that is, the current output by the LED driver is controlled by the light attenuation compensation signal and the control signal. At this time, the current output by the LED driver does not necessarily increase as the cumulative illumination time increases. It can be determined that when the control signal is unchanged, the current output by the LED driver increases as the cumulative illumination time increases.

 The light attenuation compensation signal superimposed with the control signal refers to the light attenuation compensation signal generated by the light attenuation adjustment module 3 itself and the signal synthesized by the control signal via a certain operation. Therefore, the superposition here is not in the literal sense. Add meaning, but the meaning of inclusion.

 The control signal is any one or more of a temperature compensation signal, an infrared switching signal, and a dimming signal. among them:

 The temperature compensation signal may be from a temperature compensation module, and the temperature compensation module detects the temperature of the LED light source. When the detected temperature is too high, the light attenuation adjustment module 3 outputs a light attenuation compensation signal superimposed with a temperature compensation signal indicating the temperature drop of the LED light source to Adjust the light 2 to reduce the current of the LED light source and reduce the temperature of the LED light source. While ensuring the compensation of the LED light source, the temperature of the LED light source is reduced and the life of the LED is prolonged.

 The infrared switch signal can be derived from the infrared sensor module. When the infrared sensor module detects an external obstacle, the infrared switch signal is output to the light fade adjustment module 3 to turn the LED light source on or off, that is, the light decay of the infrared switch signal superimposed on the light 2 The compensation signal controls the output current of the LED driver 1, for example, a light decay compensation signal superimposed on the dimming light 2 indicating that the infrared switch signal of the LED light source is superimposed to control the output current of the LED driver 1 to make the LED light source bright. Or, the light fading compensation signal indicating that the infrared switch signal of the LED light source is superimposed on the illuminating light 2 controls the LED driver 1 not to output current, so that the LED light source is off.

The dimming signal can come from a dimmer, such as a 0-10 V dimmer, whose output signal is A dimming level between 0-l OV size range, the light fade adjustment module 3 receives the dimming level and superimposes the light decay compensation signal generated inside the light decay adjustment module, and outputs the signal to the dimming light 2 to increase the LED light source. Brightness adjustable function. The dimming signal can also be generated by the wireless remote control module, specifically outputted by the wireless receiving module, and the wireless receiving module receives the signal sent by the wireless transmitting module to implement the wireless remote control dimming function.

 The above-described light attenuation adjustment module 3 includes a level conversion circuit 45, an MCU (Micro Control Unit) 46, and a filter 47. among them:

 The level conversion circuit 45 is configured to convert the control signal of the input end of the light decay adjustment module 3 into a control signal that meets the requirements of the MCU 45. The control signal is converted to a control signal that is within the valid range of the MCU input. The level shift circuit 45 includes: a sixth resistor 451 and a seventh resistor 452. The sixth resistor 451 and the seventh resistor 452 are connected in series between the control signal and the ground, and the connection point of the sixth resistor 451 and the seventh resistor 452 is connected to the input terminal of the MCU 46.

 The MCU46 is configured to convert the level-converted control signal and the self-generated optical attenuation compensation signal into dimming data, and convert the dimming data into a PWM (Pulse Width Modulation) signal output to the filter. Specifically, the A/D converter inside the MCU 46 converts the level-converted control signal into a digital signal, and performs a digital operation on the optical attenuation compensation signal generated by itself to obtain dimming data with optical attenuation compensation information. This dimming data is converted to a PWM signal by the PWM module inside the MCU. When the control signal is a dimming signal, the calculation formula of the dimming data is: VC=Vd*[(1-P%)+D%], where: VC is dimming data, Vd is dimming signal, D % is the light attenuation compensation increment at a certain time, ? % is the maximum light decay compensation increment.

 殳The control signal is a 2V dimming signal, and the maximum light attenuation compensation increment is 30%. At the initial illumination time, the signal size on the modulating light 2 is 2* (1-30%) = 1.4V, when the rated life is reached, The signal size on the dimming 2 is 2V.

The filter 47 filters the PWM signal and outputs a light attenuation compensation superimposed with the control signal. Signal to LED driver 1. The filter 47 includes: an eighth resistor 471 and a capacitor 472. The eighth resistor 471 is connected between the dimming light 2 and the output of the MCU 46. The capacitor 472 is connected to the connection point of the output terminal of the eighth resistor 471 and the MCU 46, and the other end is grounded.

 The LED driver 1 in the above LED driving device can adopt the structure in Fig. 3 or Fig. 4, which will not be described again. Of course, the signal conversion module 4 in Fig. 5 can also be added.

 Applying the above technical solution, while realizing the compensation of the light source of the LED light source, other parameter control of the LED light source, such as dimming control or temperature control, is realized.

 The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments are obvious to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but the scope of the inventions

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Claims

Rights request  1. A light-emitting diode LED driving device, comprising:  And a light attenuation adjustment module for generating and outputting a light attenuation compensation signal that monotonously changes at a preset rate as the illumination time increases according to a degree of attenuation of the illumination intensity of the LED light source with an increase in illumination time;  Connected between the power supply and the LED light source, and a light-adjusting LED driver is reserved, and the LED driver is connected to the light decay adjustment module through the light modulation, and is controlled by the light attenuation compensation signal on the modulated light The LED driver output current increases as the illumination time increases.  2. The LED driving device according to claim 1, wherein the light decay adjustment module is provided with a light attenuation adjustment line for adjusting a preset rate of the light decay compensation signal generated by the light decay adjustment module.  3. The LED driving device according to claim 2, wherein the light attenuation adjustment line is externally connected to a voltage signal or an external resistor;  When the voltage signal is externally connected, the level value on the light attenuation adjustment line is equal to the amplitude of the external voltage signal;  When an external resistor is connected, the external resistor is connected between the reference source of the light attenuation adjusting circuit and the voltage dividing resistor, and the level value on the light decay adjusting line is equal to the external resistor and the voltage dividing resistor pair The partial pressure value of the reference source.  4. The LED driving device according to claim 1, wherein the light attenuation adjustment module comprises: a discharge battery;  a first resistor and a second resistor connected in series across the discharge battery; The emitter is connected to the reference source, the collector is grounded through the third resistor, and the base is connected through the fourth resistor a PNP type transistor of the first resistor and the second resistor connection point, and a connection point of the collector of the PNP type transistor and the third resistor is connected to the dimming light.  The LED driving device according to claim 1, wherein the light attenuation adjustment module comprises: a discharge battery;  a fifth resistor connected across the discharge battery;  An impedance matching circuit connected between the discharge current output of the discharge battery and the modulating light.  6. The LED driving device according to claim 1, wherein the light attenuation adjustment module comprises a timing output unit and a light attenuation adjustment output unit:  The timing output unit is configured to cycle timing, and triggers the light decay adjustment output unit every time the timing time T expires;  The light attenuation adjustment output unit is configured to generate and output a light attenuation compensation signal that monotonously changes at a preset rate as the illumination time increases, and the light attenuation adjustment output unit currently outputs the light attenuation compensation signal relative to the previous output The increase or decrease value of the light decay compensation signal is the product of the preset rate a and the timing time T.  The LED driving device of claim 1 , further comprising: a dimming module connected to the LED driver by the dimming light, wherein the dimming module is configured to output a dimming signal to the dimming signal And adjusting the output current of the LED driver by the light attenuation compensation signal and the dimming signal on the modulated light.  8. The LED driving device according to claim 7, wherein the dimming module comprises a timing unit and a dimming output unit: A timing unit for segment timing, and triggering the dimming output unit to output a dimming signal every time the timing time expires. Connected to the dimming light, output dimming output units of different dimming signals according to different triggered moments.  9. The LED driving apparatus according to claim 1, further comprising a control signal applied to an input end of the light attenuation adjustment module, wherein the control signal is superimposed on the light attenuation by the light attenuation adjustment module Compensating the signal, and outputting the light decay compensation signal superimposed with the control signal to the modulated light, and controlling the LED driver output current by the light decay compensation signal superimposed with the control signal on the modulated light.  The LED driving device according to claim 9, wherein the control signal is any one or more of a temperature compensation signal, an infrared switching signal, and a dimming signal.  The LED driving device according to claim 9, wherein the light attenuation adjustment module comprises: a level conversion circuit, an input terminal connected to the control signal, a filter, and a link in the level conversion circuit and a microcontroller MCU between the filters; wherein:  The level conversion circuit is configured to convert the control signal into a control signal that meets a range of effective sizes of the MCU input end;  The MCU is configured to convert the control signal converted by the level conversion circuit and the light attenuation compensation signal generated by itself into dimming data, and convert the dimming data into a PWM signal and output the signal to the filter;  The filter performs filtering processing on the PWM signal, and outputs a light attenuation compensation signal superimposed with the control signal to the LED driver, and the control signal is converted by the level conversion circuit.  The LED driving device according to claim 11, wherein the level converting circuit comprises: a sixth resistor and a seventh resistor connected in series between the control signal and the ground, the sixth resistor A connection point to the seventh resistor is coupled to an input of the MCU. 13. The LED driving device according to claim 11, wherein the filter package Include: an eighth resistor connected between the dimming light and the output of the MCU;  One end is connected to the connection point of the eighth resistor and the output end of the MCU, and the other end is grounded. The LED driving device according to any one of claims 1 to 13, wherein the light attenuation adjustment module is connected to the modulating light through a signal conversion module, and the signal conversion module is configured to use the light The light decay compensation signal outputted by the fading adjustment module is converted into a standard light fading compensation signal within an effective size range of the modulating light, and is output to the modulating light, and the LED light driver output current is controlled by the standard light fading compensation signal on the modulating light.  The LED driving device according to any one of claims 1 to 13, wherein the LED driver and the light attenuation adjustment module are separately packaged.