CN113675817B - Overvoltage protection circuit, overvoltage protection method and chip - Google Patents
Overvoltage protection circuit, overvoltage protection method and chip Download PDFInfo
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- CN113675817B CN113675817B CN202110753230.5A CN202110753230A CN113675817B CN 113675817 B CN113675817 B CN 113675817B CN 202110753230 A CN202110753230 A CN 202110753230A CN 113675817 B CN113675817 B CN 113675817B
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- 238000005070 sampling Methods 0.000 claims abstract description 342
- 238000001514 detection method Methods 0.000 claims abstract description 104
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- 230000001105 regulatory effect Effects 0.000 claims description 2
- 238000010586 diagram Methods 0.000 description 15
- 239000003990 capacitor Substances 0.000 description 7
- 238000004804 winding Methods 0.000 description 5
- 230000005669 field effect Effects 0.000 description 4
- 230000005405 multipole Effects 0.000 description 4
- 230000001276 controlling effect Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000005347 demagnetization Effects 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
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- 101000650775 Boana raniceps Raniseptin-1 Proteins 0.000 description 1
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/20—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess voltage
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/006—Calibration or setting of parameters
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/10—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers
- H02H7/12—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers
- H02H7/1213—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers for DC-DC converters
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of DC power input into DC power output
- H02M3/22—Conversion of DC power input into DC power output with intermediate conversion into AC
- H02M3/24—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters
- H02M3/28—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC
- H02M3/325—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33507—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of the output voltage or current, e.g. flyback converters
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- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
- Protection Of Static Devices (AREA)
Abstract
The invention relates to an overvoltage protection circuit, an overvoltage protection method and a chip, belonging to the technical field of electronic circuits and comprising a sampling processing module, a sampling detection module and a control module; for the sampling processing module, a voltage signal input end is used for acquiring a voltage signal input to an external load circuit, a sampling proportion control signal input end is used for acquiring a sampling proportion control signal, the sampling processing module is configured to generate a voltage sampling signal according to the sampling proportion control signal and the voltage signal, and a sampling signal output end is used for outputting the voltage sampling signal; the sampling detection module is used for acquiring a reference voltage signal and a voltage sampling signal, comparing the reference voltage signal with the voltage sampling signal and generating a detection result signal; the control module is configured to generate a sampling proportion control signal according to the detection result signal and perform overvoltage protection processing on the load circuit when the detection result signal meets a preset condition. The invention can conveniently meet different output voltage levels.
Description
Technical Field
The invention relates to the technical field of electronic circuits, in particular to an overvoltage protection circuit, an overvoltage protection method and a chip.
Background
In switching power supply system design, it is often necessary to measure the output voltage and perform overvoltage protection. In the related art, the output voltage is generally obtained by directly sampling the output voltage or sampling the voltage of the auxiliary coil by adopting resistance voltage division, then the sampled voltage is compared with the reference voltage by using an overvoltage protection circuit, if the sampled voltage is higher than the reference voltage, the overvoltage is determined, and then the output is turned off, so that the purpose of overvoltage protection is realized.
In view of the above-mentioned related technologies, the inventor believes that in practical power supply applications, the output voltage is divided into a plurality of levels and the variation range is large, whereas in some power supply systems with fixed hardware structures, different output voltage levels are not convenient to satisfy due to the relatively fixed overvoltage protection threshold value, and the adaptation range is small.
Disclosure of Invention
In order to meet different output voltage grades, the invention provides an overvoltage protection circuit, an overvoltage protection method and a chip.
In a first aspect, the present invention provides an overvoltage protection circuit, which adopts the following technical scheme:
an overvoltage protection circuit comprises a sampling processing module provided with a voltage signal input end, a sampling proportion control signal input end and a sampling signal output end; the sampling processing module is configured to generate a voltage sampling signal according to the sampling proportion control signal and the voltage signal, the proportion between the voltage signal and the voltage sampling signal is consistent with the sampling proportion represented by the sampling proportion control signal, and the sampling signal output end is used for outputting the voltage sampling signal;
the sampling detection module is connected with the sampling signal output end and used for acquiring a reference voltage signal and a voltage sampling signal, comparing the reference voltage signal with the voltage sampling signal and generating a detection result signal;
and the control module is respectively connected with the sampling proportion control signal input end and the sampling detection module, and is configured to generate a sampling proportion control signal according to the detection result signal and carry out overvoltage protection processing on the load circuit when the detection result signal meets the preset condition.
In a second aspect, the invention provides an overvoltage protection method, which adopts the following technical scheme:
an overvoltage protection method is applied to an overvoltage protection circuit comprising a sampling processing module, a sampling detection module and a control module, and comprises the following steps:
acquiring a detection result signal output by the sampling detection module, wherein the detection result signal is generated by the sampling detection module according to the voltage sampling signal and the reference voltage signal;
generating a sampling proportion control signal according to the detection result signal;
sending the sampling proportion control signal to a sampling processing module so that the sampling processing module generates a voltage sampling signal according to the sampling proportion control signal and a voltage signal input to an external load circuit, wherein the proportion between the voltage signal and the voltage sampling signal is consistent with the sampling proportion represented by the sampling proportion control signal; and the number of the first and second groups,
and carrying out overvoltage protection processing on the load circuit when the detection result signal meets the preset condition.
In a third aspect, the present invention provides a chip, which adopts the following technical solutions:
a chip comprising an overvoltage protection circuit as claimed in any one of the first aspect.
In summary, the invention includes at least one of the following beneficial technical effects: by adopting the overvoltage protection circuit comprising the sampling processing module, the sampling detection module and the control module, provided by the invention, the overvoltage protection processing can be carried out on the load circuit when the detection result signal meets the preset condition, namely the voltage value represented by the voltage signal is greater than the actual overvoltage protection threshold value; meanwhile, the sampling proportion is adjusted through the sampling proportion control signal, and then the requirements of actual overvoltage protection threshold values of different circuits can be met, so that different output voltage grades can be met conveniently, and the application range is widened.
Drawings
Fig. 1 is a schematic diagram of an overvoltage protection circuit according to an embodiment of the present invention.
Fig. 2 is a schematic diagram of an overvoltage protection circuit according to an embodiment of the present invention.
Fig. 3 is a schematic diagram of an overvoltage protection circuit according to an embodiment of the invention.
Fig. 4 is a schematic diagram of an overvoltage protection circuit according to an embodiment of the invention.
Fig. 5 is a schematic diagram of an overvoltage protection circuit according to an embodiment of the invention.
Fig. 6 is a schematic diagram of an overvoltage protection circuit according to an embodiment of the invention.
Fig. 7 is a schematic diagram of an overvoltage protection circuit according to an embodiment of the invention.
Fig. 8 is a schematic diagram of an overvoltage protection circuit according to an embodiment of the invention.
Fig. 9 is a schematic structural diagram of an overvoltage protection circuit applied to a flyback circuit according to an embodiment of the present invention.
Fig. 10 is a schematic circuit diagram of a flyback circuit according to an embodiment of the present invention.
Fig. 11 is a schematic circuit diagram of an overvoltage protection circuit applied to a flyback circuit according to an embodiment of the present invention.
FIG. 12 is a first k proportional switches φ of one embodiment of the present invention1、φ2、φ3、…、φkAnd (3) a change curve diagram of the voltage sampling signal when closing sequentially.
FIG. 13 is a timing diagram of voltage signal sampling according to one embodiment of the present invention.
Fig. 14 is a flow chart of an overvoltage protection method according to one embodiment of the invention.
Fig. 15 is a schematic structural diagram of a chip according to an embodiment of the present invention.
Description of reference numerals: 11. a sampling processing module; 111. a first resistor; 112. a second resistor; 113. a proportional switch; 114. a voltage dividing unit; 12. a sampling detection module; 13. a control module; 14. a reference terminal; 15. a reference voltage generation module; 151. a reference voltage unit; 152. a multiplexer; 16. a sampling control switch module; 17. a capacitive module; 200. a load circuit; 21. a voltage transformation module; 211. a primary coil; 212. a secondary coil; 213. an auxiliary coil; 22. a switching converter.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to fig. 1-15 and the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
In a conventional power supply system, there is generally only a single internal reference voltage inside the controller, and when the hardware structure is relatively fixed, the overvoltage protection threshold is also relatively fixed. In practical power supply application, the output voltage is often divided into multiple levels, the variation range is large, and a single overvoltage protection threshold value cannot meet multiple output voltage levels.
For example, when the output voltage levels are 5V, 12V, 15V, and 20V, respectively, if the overvoltage protection threshold is designed according to the highest output voltage level of 20V, the overvoltage protection will fail when the output voltage is a low voltage level; if the over-voltage protection threshold is designed to a minimum output voltage level of 5V, over-protection occurs when the output voltage is at a high voltage level, causing the output to latch. Therefore, it is desirable to design an overvoltage protection circuit and method thereof that can satisfy different output voltage levels.
The embodiment of the invention discloses an overvoltage protection circuit.
Referring to fig. 1, the overvoltage protection circuit includes a sampling processing module 11, a sampling detection module 12, and a control module 13. The sampling processing module 11 is provided with a voltage signal input end, a sampling proportion control signal input end and a sampling signal output end; the voltage signal input terminal is configured to obtain a voltage signal input to the external load circuit 200, the sampling ratio control signal input terminal is configured to obtain a sampling ratio control signal, the sampling processing module 11 is configured to generate a voltage sampling signal according to the sampling ratio control signal and the voltage signal, a ratio between the voltage signal and the voltage sampling signal is consistent with a sampling ratio represented by the sampling ratio control signal, and the sampling signal output terminal is configured to output the voltage sampling signal. The sampling detection module 12 is connected to the sampling signal output end of the sampling processing module 11, and the sampling detection module 12 is configured to obtain a reference voltage signal and a voltage sampling signal, compare the reference voltage signal with the voltage sampling signal, and generate a detection result signal. The control module 13 is connected to the sampling ratio control signal input end of the sampling processing module 11 and the sampling detection module 12, respectively, and the control module 13 is configured to generate a sampling ratio control signal according to the detection result signal and perform overvoltage protection processing on the load circuit 200 when the detection result signal meets a preset condition.
The "external load circuit 200" described in this embodiment is "external" with respect to the overvoltage protection circuit, and is not limited to "external" of the carrier on which the overvoltage protection circuit is located, and this description is for distinguishing the overvoltage protection circuit provided in this embodiment from the load circuit 200, and is not specific to the location where the overvoltage protection circuit is located.
In this embodiment, the load circuit 200 may include a circuit capable of utilizing electric energy to do work, for example, the circuit may be an electronic component driving circuit such as a light emitting diode, a field effect transistor, a resistor, a coil, and the like; the load circuit 200 may further include a circuit capable of storing and discharging electric energy, for example, the circuit may include a circuit including a battery, an adapter, and the like, and the specific structure of the load circuit 200 is not particularly limited herein.
In this embodiment, the sampling processing module 11 may receive a sampling ratio control signal sent by the control module 13, and when the sampling processing module 11 receives the sampling ratio control signal, the sampling processing module may adjust the voltage signal received by the voltage signal input end to the voltage sampling signal according to a sampling ratio represented by the sampling ratio control signal, and output the voltage sampling signal through the sampling signal output end, where a ratio between a voltage value represented by the voltage signal and a voltage value represented by the voltage sampling signal should be consistent with the sampling ratio represented by the sampling ratio control signal. That is, the control module 13 may control the voltage represented by the sampled voltage signal output by the sampled signal output terminal through the sampling ratio control signal.
Referring to fig. 2, in this embodiment, the sampling processing module 11 may include a voltage dividing unit 114, and the voltage dividing unit 114 may be connected between a voltage signal input end and a sampling signal output end of the sampling processing module 11, and meanwhile, the voltage dividing unit 114 may also be connected with the control module 13. The control module 13 may send a sampling ratio control signal to the voltage dividing unit 114, and when the voltage dividing unit 114 receives the sampling ratio control signal, based on a mapping relationship between the sampling ratio control signal and a working state of the voltage dividing unit 114, the voltage dividing unit 114 starts a corresponding working state; for example, the voltage dividing unit 114 can be used to start the voltage dividing function and to turn off the voltage dividing function. Therefore, the voltage of the sampling signal output end can be controlled by adopting the voltage division unit 114.
Further, when the number of the voltage dividing units 114 is multiple (greater than or equal to two), at this time, the sampling ratio can be adjusted more accurately by controlling the operating states of the voltage dividing units 114, and meanwhile, the selectivity of the sampling ratio is more, so that the overvoltage protection circuit provided by the embodiment can be applied to wider circuits.
As an embodiment of the connection manner of the plurality of voltage division units 114, referring to fig. 2, the plurality of voltage division units 114 may be sequentially connected in series between the voltage signal input terminal and the sampling signal output terminal. It should be noted that the connection manner of the plurality of voltage dividing units 114 may be determined based on the specific electronic components of the voltage dividing unit 114, and the connection manner of the voltage dividing unit 114 is not particularly limited.
Further, referring to the embodiment shown in fig. 3, when a plurality of voltage dividing units 114 are connected in series between the voltage signal input terminal and the sampling signal output terminal, the voltage dividing unit 114 may include a voltage dividing resistor Rxn and a switch Kxn connected in parallel with the voltage dividing resistor Rxn; at this time, a plurality of voltage dividing resistors (Rx 1, Rx2, …, RXn) connected in series are provided between the voltage signal input terminal and the sampling signal output terminal, and switches (Kx 1, Kx2, …, KXn) are correspondingly provided, n is a natural number greater than or equal to 1, and the specific number of n may be determined based on actual design requirements of the voltage dividing unit 114. The voltage dividing resistor Rxn may include a wire resistor, a thin film resistor, a solid resistor, a sensitive resistor, and the like, and the type of the voltage dividing resistor Rxn is not particularly limited. The switch Kxn may include a single-pole unit switch, a double-pole two-position switch, a single-pole multi-position switch, a multi-pole unit switch, a multi-pole multi-position switch, etc., and the type of the switch Kxn is not particularly limited herein.
In the embodiment shown in fig. 3, the control module 13 may control on/off of the switch Kxn, when the control module 13 controls the switch Kxn to be switched off, the resistor Rxn connected in parallel with the switch Kxn may perform a voltage division function, and the voltage division unit 114 connected to the switch Kxn starts a voltage division function, so as to reduce the voltage at the output end of the sampling signal; when the control module 13 controls the switch Kxn to be closed, the resistor Rxn connected in parallel with the switch Kxn cannot perform a voltage division function, and the voltage division unit 114 connected with the switch Kxn turns off the voltage division function, so that the voltage at the output end of the sampling signal is increased. Therefore, the control module 13 can control the voltage of the sampling signal output end, and can further adjust the proportion between the voltage value represented by the voltage signal and the voltage value represented by the sampling voltage signal.
In this embodiment, the sampling detection module 12 may include a circuit for comparing the reference voltage signal with the voltage sampling signal. For example, the sampling detection module 12 may be a comparator, one end of the comparator may obtain a reference voltage signal, and the other end of the comparator may be connected to the sampling signal output end to obtain a sampling voltage signal, so as to compare the reference voltage signal with the sampling voltage signal, thereby obtaining a detection result signal.
In this embodiment, the control module 13 may perform the overvoltage protection process on the load circuit 200 when the detection result signal meets the preset condition. The preset condition may be determined based on an actual requirement, for example, when the load circuit 200 is determined to be in an overvoltage state according to the detection result signal, the control module 13 may control to open the circuit for supplying power to the load circuit 200.
In addition, the control module 13 may determine a sampling ratio control signal based on the detection result signal. For example, when the detection result signal determines that the voltage value represented by the voltage sampling signal is greater than the voltage value represented by the reference voltage signal, the control module 13 may generate the sampling ratio control signal to decrease the sampling ratio, so as to decrease the voltage value represented by the sampled voltage sampling signal. Therefore, the overvoltage protection circuit provided by the embodiment can adjust the sampling proportion to meet the requirements of actual overvoltage protection threshold values of different circuits.
In this embodiment, by using the overvoltage protection circuit including the sampling processing module 11, the sampling detection module 12, and the control module 13 provided in this embodiment, when the detection result signal meets the preset condition, that is, when the voltage value represented by the voltage signal is greater than the actual overvoltage protection threshold, the overvoltage protection processing can be performed on the load circuit 200; meanwhile, the sampling proportion is adjusted through the sampling proportion control signal, the requirements of actual overvoltage protection threshold values of different circuits can be met, different output voltage grades can be conveniently met, and the application range of the overvoltage protection circuit provided by the embodiment is widened.
As a further embodiment of the overvoltage protection circuit, referring to fig. 4, the sampling processing module 11 may include one or more scaling units; the proportional adjustment unit may include a first resistor 111, a second resistor 112, and a proportional switch 113; a first end of the first resistor 111 is connected with a voltage signal input end of the sampling processing module 11, a common junction formed by a second end of the first resistor 111 and the second resistor 112 is connected with a sampling signal output end of the sampling processing module 11, and the second resistor 112 and the proportional switch are connected between the common junction and the reference end 14 in series; the proportional switch 113 is configured to adjust the on-off state based on the sampling proportional control signal; the resistance value of the first resistor 111 is equal to or greater than 0.
Wherein, each of the first resistor 111 and the second resistor 112 may include a wire resistor, a thin film resistor, a solid resistor, a sensitive resistor, etc., and the type of the first resistor 111 and the second resistor 112 is not particularly limited herein; the proportional switch 113 may include a single-pole unit switch, a double-pole two-position switch, a single-pole multi-position switch, a multi-pole unit switch, a multi-pole multi-position switch, etc., and the type of the proportional switch 113 is not particularly limited herein.
It should be noted that the reference terminal 14 can be a reference ground terminal, an analog ground terminal, and other connection terminals with a specified voltage.
In this embodiment, the proportional switch 113 may be connected to the control module 13, and the control module 13 controls on/off of the proportional switch 113 through sampling the proportional control signal. For example, when the proportional switch 113 is a field effect transistor, the control module 13 may be connected to a gate of the field effect transistor, and output a sampling proportional control signal (at this time, the sampling proportional control signal may be a high level signal or a low level signal), so as to control the on/off of the field effect transistor, so as to control the on/off state between the second resistor 112 and the proportional switch 113; it should be noted that the corresponding switch type can be set based on the actual setting requirement of the manufacturer for the proportional switch 113, and the type of the sampling proportional control signal output by the control module 13 can be adjusted accordingly.
Further, when the control module 13 controls the proportional switch 113 to be turned on, the second resistor 112 connected in series with the proportional switch 113 may perform a voltage division function, so as to reduce the voltage at the sampling signal output end; when the control module 13 controls the proportional switch 113 to be turned off, the second resistor 112 connected in series with the proportional switch 113 cannot perform a voltage division function, so that the voltage at the sampling signal output terminal is increased. Therefore, the control module 13 can control the voltage of the sampling signal output end, and can further adjust the proportion between the voltage value represented by the voltage signal and the voltage value represented by the sampling voltage signal.
As an embodiment when the number of the proportional adjusting units is greater than or equal to two, referring to fig. 5, at least two first resistors 111 are sequentially connected in series to form a first series circuit, at least one second resistor 112 is connected in series with at least one proportional switch 113 to form a second series circuit, and the number of the second series circuits is greater than or equal to two; the first series circuit is connected between the voltage signal input terminal and the sampling signal output terminal of the sampling processing module 11, and at least one second series circuit is connected between the second terminals of the at least two first resistors 111 and the reference terminal 14, respectively.
In this embodiment, assuming that the number of the proportion adjusting units is n, that is, n levels of proportion adjusting units are correspondingly arranged, where n is a natural number greater than 2; the resistance values of the n first resistors 111 (Rss 1, Rss2, Rss3, …, Rssn) may be 0, or may be other set values, and the set values may be preset according to actual requirements; the n proportional switches 113 (φ 1, φ 2, φ 3, …, φ n) may not be closed, and may be closed only one or a plurality of at the same time.
In this embodiment, by setting the plurality of proportional control units and controlling the on-off states of the plurality of proportional switches 113, the sampling proportion can be adjusted more accurately, the sampling proportion can be adjusted in multiple stages, and the selectivity of the overvoltage protection threshold is increased; meanwhile, compared with the mode of adjusting the ratio between the voltage of the voltage signal input end and the voltage of the sampling signal output end as shown in fig. 2 and 3, the mode of setting a plurality of ratio adjusting units is more stable, and can prevent large voltage or large current from causing large impact on the sampling processing module 11.
As a further embodiment of the overvoltage protection circuit, referring to fig. 6, the sampling detection module 12 may have a first input terminal, a second input terminal, and an output terminal, the first input terminal is connected to the sampling signal output terminal of the sampling processing module 11, and the output terminal is connected to the control module 13; the overvoltage protection circuit further comprises a reference voltage generation module 15, and the reference voltage generation module 15 is connected between the second input end and the control module 13; the control module 13 is further configured to output a reference voltage control signal according to the detection result signal, and the reference voltage generating module 15 is configured to output a reference voltage signal corresponding to the reference voltage control signal to the second input terminal.
In the present embodiment, the control module 13 may determine the reference voltage control signal based on the detection result signal; for example, when the detection result signal determines that the voltage value represented by the voltage sampling signal is greater than the voltage value represented by the reference voltage signal, the control module 13 may use the reference voltage control signal to increase the voltage value represented by the reference voltage signal. Therefore, the overvoltage protection circuit provided by the embodiment can adjust the voltage value represented by the reference voltage signal so as to adapt to the requirements of actual overvoltage protection threshold values of different circuits.
As an embodiment of the reference voltage generating module 15, referring to fig. 7, the reference voltage generating module 15 may include a reference voltage unit 151 and a multiplexer 152; the multiplexer 152 includes a reference voltage signal input terminal, a reference voltage signal output terminal, and a reference voltage control signal input terminal; the reference voltage signal input terminal may be connected to the reference voltage unit 151, and configured to receive a plurality of reference voltage signals generated by the reference voltage unit 151. The reference voltage control signal input terminal may be connected to the reference voltage control signal output terminal of the control module 13, and configured to receive the reference voltage control signal. The multiplexer 152 may select one of the plurality of reference voltage signals to be output as the reference voltage signal according to the reference voltage control signal. The reference voltage signal output end is connected to the second input end of the sampling detection module 12, and is used for outputting a reference voltage signal. In this embodiment, the reference voltage unit 151 may provide the reference voltage signal using a reference source, and the multiplexer 152 may use a type of multiplexer switch such as 4-to-1, double 4-to-1, 8-to-1, etc. according to the requirement.
In the present embodiment, x reference voltage signals V are generated by the reference voltage unit 151REFE1、VREFE2、VREFE3、…、VREFxThe control module 13 generates m reference voltage control signals S1, S2, S3, …, Sm to be transmitted to the multiplexer 152, and the multiplexer 152 selects x (x) according to the reference voltage control signals<And =2 m) reference voltage signals are output as the reference voltage signals, so that the voltage value represented by the reference voltage signals is adjusted.
In addition, as another embodiment of the reference voltage generating module 15, the reference voltage generating module 15 may also adopt a digital-to-analog converter DAC, a digital signal input end of the digital-to-analog converter DAC is connected to the reference voltage control signal output end of the control module 13, and an analog signal output end of the digital-to-analog converter DAC is connected to the second input end of the sampling detection module 12; the digital-to-analog converter DAC receives the m reference voltage control signals S1, S2, S3, …, Sm sent by the control module 13, and generates and outputs the reference voltage signals corresponding to the m reference voltage control signals, so that the adjustment of the voltage value represented by the reference voltage signals can be realized in the same way.
In the above embodiment, the control module 13 outputs the reference voltage control signal according to the detection result signal, and further adjusts the voltage value represented by the reference voltage signal, thereby implementing adjustment of the overvoltage protection threshold; by using m reference voltage control signals, 2 can be generatedmThe reference voltage is used, so that the adaptive range is further improved.
It should be noted that the control module 13 not only can generate the sampling ratio control signal and the reference voltage control signal according to the detection result signal after receiving the detection result signal, but also can pre-adjust the overvoltage protection threshold by sending the sampling ratio control signal and the reference voltage control signal in advance according to the actual situation.
As a further embodiment of the overvoltage protection circuit, referring to fig. 8, the overvoltage protection circuit may further include a sampling control switch module 16, where the sampling control switch module 16 is connected between the sampling processing module 11 and the sampling detection module 12; the sampling control switch module 16 is configured to turn on when the voltage value represented by the voltage sampling signal is greater than zero.
In the embodiment, by setting the sampling control switch module 16, when the voltage value represented by the voltage sampling voltage is a positive voltage, the sampling control switch φ s is turned on; when the voltage value represented by the voltage sampling voltage is negative voltage, the sampling control switch phi s is turned off, so that the sampling detection can be prevented from being carried out when the sampling signal output end is negative voltage to a certain extent, the working frequency of the sampling detection module 12 is reduced, and the effect of reducing energy consumption is achieved.
As a further embodiment of the overvoltage protection circuit, referring to fig. 8, the overvoltage protection circuit may further include a capacitor module 17, a common junction formed by the sampling control switch module 16 and the sampling detection module 12 is connected to a first end of the capacitor module 17, and a second end of the capacitor module 17 is connected to the reference terminal 14.
It should be noted that the "common junction" in this embodiment is used to describe the circuit structure between the capacitance module 17 and the sampling control switch module 16 and the sampling detection module 12, and it should not be limited to a specific intersection formed by connecting only two or more wire bodies, and it may be a wire body extending on the basis of a specific intersection formed by connecting two or more wire bodies, and is not limited in particular here.
In this embodiment, the capacitor module 17 is used to keep the output voltage after sampling unchanged during the sampling processing time, thereby ensuring the accuracy of sampling detection and reducing the sampling error.
As an embodiment of the overvoltage protection circuit applied to the flyback circuit, referring to fig. 9, the load circuit 200 may include a flyback circuit including a voltage transformation module 21 provided with a primary coil 211, a secondary coil 212, and an auxiliary coil 213, and a switch converter 22 connected to the primary coil 211; the control module 13 is connected to the switching converter 22, and the voltage signal input terminal of the sampling processing module 11 is connected to the auxiliary winding 213.
The flyback circuit is a circuit for isolating an input circuit and an output circuit by using a flyback high-frequency transformer.
Referring to fig. 9 and 10, in the present embodiment, the flyback circuit is connected to a chip integrated with the overvoltage protection circuit; wherein Lp is a primary coil, Ls is a secondary coil, La is an auxiliary coil, and the voltage output end V of the secondary coil LsOUTA voltage input terminal connected to the load circuit 200; the switch converter 22 comprises a switch tube U1, and the switch control signal input end of the switch tube U1 is connected to the control signal output end Gate of the chip and used for receiving the switch control signal; the switch control signal is generated by a control module 13 in the chip, and the switch control signal output end of the control module 13 is connected to the control signal output end Gate of the chip; the switch control signal is used for controlling the switching tube U1 to be turned on and off.
As an embodiment of the switch control signal, the switch control signal may include a switch open signal and a switch close signal; when the input switch closing signal is input, the switch tube U1 is closed, and the voltage input end V is passedINCharging the primary coil Lp; when the input switch off signal is input, the switching tube U1 is turned off, and the output current of the secondary coil Ls supplies power to the load circuit 200. Therefore, when the detection result signal meets the preset condition, the control module 13 generates a switch closing signal, so that the power supply to the load circuit 200 can be stopped.
In the present embodiment, when the output current of the secondary coil Ls supplies power to the load circuit 200, the output voltage of the secondary coil Ls is VOUT+VDIn which V isDIs a secondary rectifier diodeA voltage drop, during which the auxiliary winding La excites a voltage V proportional to the secondary windingAUX=(VOUT+VD) N, wherein n is the turn ratio of the secondary coil Ls to the auxiliary coil La; an auxiliary voltage output end V of the auxiliary coil La is divided by a first voltage dividing resistor R1 and a second voltage dividing resistor R2AUXSampling is carried out, so that the voltage output end V of the secondary coil Ls can be obtainedOUTI.e., a voltage value that is indicative of a voltage signal coupled to the load circuit 200.
Therefore, the voltage signal input terminal of the sampling processing module 11 is connected to the voltage output terminal V of the auxiliary coil LaAUXA voltage signal input to the external load circuit 200 can be acquired; in addition, the voltage signal input terminal of the sampling processing module 11 can also be connected to the voltage output terminal V of the secondary coil LsOUTThe voltage signal input to the external load circuit 200 can be acquired as well.
Referring to fig. 10 and 11, as an embodiment of the overvoltage protection circuit applied to the flyback circuit, a voltage signal input terminal of the sampling processing module 11 is connected to a voltage sampling terminal ZCD of the chip, a sampling signal output terminal of the sampling processing module 11 is connected to a first input terminal of the sampling detection module 12, the sampling processing module 11 includes n stages of proportional control units (n is a natural number greater than 1), and each stage of proportional control unit includes a first resistor RssiA second resistor RspiAnd proportional switch phii(ii) a The sampling control switch module 16 comprises a sampling control switch φ s, a first end of the sampling control switch φ s is connected to a sampling signal output end of the sampling processing module 11, and a second end of the sampling control switch φ s is connected to a first input end of the sampling detection module 12; the capacitance module 17 includes a holding capacitor Cs, a first terminal of the holding capacitor Cs is connected to the second terminal of the sampling control switch Φ s, and a second terminal of the holding capacitor Cs is connected to the reference terminal 14; the sampling detection module 12 includes a voltage comparator U2, a non-inverting input terminal of the voltage comparator U2 is connected to the first input terminal of the sampling detection module 12, an inverting input terminal of the voltage comparator U2 is connected to the second input terminal of the sampling detection module 12, and an output terminal of the voltage comparator U2 is connected to the output terminal of the sampling detection module 12(ii) a A reference voltage signal output end of the reference voltage generating module 15 is connected to a first input end of the sampling detection module 12; the detection result signal input end of the control module 13 is connected to the output end of the sampling detection module 12, and the switch control signal output end of the control module 13 is connected to the control signal output end Gate of the chip.
In the present embodiment, the sampling processing module 11 generates a voltage sampling signal V according to the sampling ratio and the output voltage of the secondary coil LssampleThe voltage sampling signal V is compared by a voltage comparator U2sampleCharacterized voltage value and reference voltage signal VREFComparing the represented voltage values to judge whether the voltage value represented by the voltage signal accessed to the load circuit 200 exceeds an actual overvoltage protection threshold value or not, and outputting a detection result signal; when the detection result signal meets a preset condition, that is, when the voltage value represented by the voltage signal is greater than the actual overvoltage protection threshold value, the control module 13 outputs a switch closing signal to stop the power supply of the secondary coil Ls to the load circuit 200, that is, to perform overvoltage protection processing on the load circuit 200; meanwhile, the control module 13 generates a sampling proportion control signal according to the detection result signal to adjust the sampling proportion, so that the requirements of actual overvoltage protection threshold values of different circuits can be met, different output voltage grades can be conveniently met, and the application range is improved.
Referring to fig. 11 and 12, when the reference voltage signal is constant, fig. 12 is a graph showing a change curve of the voltage sampling signal when the first k proportional switches Φ 1, Φ 2, Φ 3, …, Φ k are sequentially closed, where k is a natural number greater than 0; when the primary proportional switch phi 1 is closed, the primary second resistor Rsp1 is switched in to enable the sampling processing module 11 to reach the primary sampling proportion, and enable the overvoltage protection threshold to reach the primary overvoltage protection threshold; when the voltage signal exceeds the reference voltage signal after being sampled at the first-stage sampling proportion, the control module 13 receives the detection result signal and sends a sampling proportion control signal to control the second-stage proportional switch phi 2 to be closed, and the second-stage second resistor Rsp2 is connected to reduce the sampling proportion to the second-stage sampling proportion, so that the overvoltage protection threshold value reaches the second-stage overvoltage protection threshold valueA threshold value; when the voltage signal input to the external load circuit 200 is continuously increased and exceeds the reference voltage signal again after the sampling processing of the second-level sampling proportion, the control module 13 sends a sampling proportion control signal according to the detection result signal to control the third-level proportional switch phi 3 to be closed, the third-level second resistor Rsp3 is connected to reduce the sampling proportion to the third-level sampling proportion, so that the overvoltage protection threshold value reaches the third-level overvoltage protection threshold value, and the like. The sampling proportion control signal controls the on-off of n proportional switches corresponding to the n-stage proportional regulating units, and 2 can be realized in totalnAn overvoltage protection threshold.
It should be noted that, when the overvoltage protection threshold is adjusted to the n-level overvoltage protection threshold or the preset overvoltage protection threshold, and the voltage value represented by the voltage sampling signal is still greater than the voltage value represented by the reference voltage signal, it is determined that the voltage signal accessed to the load circuit 200 is greater than the n-level overvoltage protection threshold or the preset overvoltage protection threshold, that is, the detection result signal satisfies the preset condition, and the control module 13 may perform the overvoltage protection processing on the load circuit 200.
Referring to fig. 10, 11 and 13 as an embodiment of sampling a voltage signal inputted to the load circuit 200, fig. 13 is a voltage signal sampling timing chart, where when a high-level signal is inputted to the switching tube U1 from the control signal output terminal Gate of the chip, the switching tube U1 is closed, and the auxiliary voltage output terminal V of the auxiliary coil La is turned onAUXAnd a voltage output terminal V of the secondary winding LsOUTThe output voltage is negative voltage, and the sampling control switch phi s is disconnected at the moment, and the sampling is stopped; when the control signal output end Gate of the chip inputs a low level signal to the switch tube U1, the switch tube U1 is disconnected, and the auxiliary voltage output end V of the auxiliary coil La is connected with the auxiliary voltage output end V of the auxiliary coil LaAUXAnd a voltage output terminal V of the secondary winding LsOUTThe output voltage is positive voltage and is maintained at constant voltage before demagnetization is finished, and at a certain moment in the period, the sampling switch phi s is closed, so that the voltage signal accessed to the load circuit 200 can be sampled to obtain sampling voltage; wherein demagnetization refers to a process in which the stored electric energy of the primary coil Ls disappears.
In order to meet different output voltage levels, the embodiment of the invention also discloses an overvoltage protection method based on the control module 13 side.
Referring to fig. 14, an overvoltage protection method may be applied to an overvoltage protection circuit including a sampling processing module 11, a sampling detection module 12, and a control module 13, and the overvoltage protection method includes:
step S11, obtaining a detection result signal output by the sampling detection module 12, where the detection result signal is generated by the sampling detection module 12 according to the voltage sampling signal and the reference voltage signal.
The detection result signal is a comparison result obtained by comparing the voltage value represented by the voltage sampling signal with the voltage value represented by the reference voltage signal.
In step S12, a sampling ratio control signal is generated based on the detection result signal.
The sampling proportion refers to the proportion between a voltage value represented by the voltage signal and a voltage value represented by the sampling voltage signal, and the sampling proportion control signal is used for adjusting the sampling proportion.
Step S13, sending the sampling ratio control signal to the sampling processing module 11, so that the sampling processing module 11 generates a voltage sampling signal according to the sampling ratio control signal and the voltage signal input to the external load circuit 200, and the ratio between the voltage signal and the voltage sampling signal is consistent with the sampling ratio represented by the sampling ratio control signal.
The voltage signal input to the external load circuit 200 is multiplied by the sampling ratio represented by the sampling ratio control signal, so that a voltage sampling signal is obtained.
In step S14, when the detection result signal meets the preset condition, the load circuit 200 is subjected to overvoltage protection processing.
The preset condition may be predetermined based on an actual requirement, for example, when the voltage value represented by the voltage signal is greater than the actual overvoltage protection threshold, it is determined that the load circuit 200 is in an overvoltage state, and the control module 13 may control to disconnect power supply to the load circuit 200, so as to implement the overvoltage protection processing.
It should be noted that the overvoltage protection method provided in this embodiment may be regarded as a method executed by the control module 13 in the overvoltage protection circuit provided in the above embodiment, and therefore, for specific execution steps of the overvoltage protection method provided in this embodiment, reference may be made to the description of the overvoltage protection circuit in the above embodiment, and details are not described here. It should also be understood that, for the detailed implementation method of the overvoltage protection method in this embodiment, reference may be made to the implementation logic of the control module 13 in the overvoltage protection circuit in the above embodiment, and the implementation logics of the two are the same, and are not described herein again.
In addition, the contents of the sampling processing module 11, the sampling detection module 12, and the control module 13 in the overvoltage protection circuit provided in the above embodiment can be referred to, and are not described again here.
In the above embodiment, the sampling detection module 12 is used to compare the voltage sampling signal with the reference voltage signal to obtain a detection result signal, and when the detection result signal meets a preset condition, that is, when the voltage value represented by the voltage signal is greater than the actual overvoltage protection threshold, the overvoltage protection processing is performed on the load circuit 200; meanwhile, the sampling proportion is adjusted through the sampling proportion control signal, and then the requirements of actual overvoltage protection threshold values of different circuits can be met, so that different output voltage grades can be met conveniently, and the application range is widened.
As a further embodiment of the overvoltage protection method, generating the sampling proportion control signal according to the detection result signal includes generating the sampling proportion control signal for decreasing the sampling proportion if it is determined from the detection result signal that the voltage value represented by the voltage sampling signal is greater than or equal to the voltage value represented by the reference voltage signal, and/or generating the reference voltage control signal for increasing the voltage value represented by the reference voltage signal.
In the above embodiment, when it is detected that the voltage value represented by the voltage sampling signal is greater than or equal to the voltage value represented by the reference voltage signal, the sampling ratio may be reduced by the sampling ratio control signal, so that the voltage value represented by the voltage sampling signal after sampling processing according to the sampling ratio is lower than the voltage value represented by the reference voltage signal, that is, the overvoltage protection threshold may be adjusted to be increased and greater than the voltage value represented by the voltage signal connected to the load circuit 200; the voltage value represented by the reference voltage signal can be increased through the reference voltage control signal, so that the voltage value represented by the reference voltage signal is increased and is greater than the voltage value represented by the voltage sampling signal, and the effect of adjusting the increase of the overvoltage protection threshold value can be achieved.
Since the sampling proportion is adjusted by the sampling proportion control signal, the overvoltage protection threshold value can be adjusted, and therefore, the preset conditions can also be set as follows: and when the voltage value represented by the voltage signal is greater than the preset overvoltage protection threshold or the adjustable maximum overvoltage protection threshold, namely the preset condition is met, performing overvoltage protection processing.
The overvoltage protection method is explained in detail by the following embodiments, and the overvoltage protection method includes: the sampling processing module 11 acquires a voltage signal input to the external load circuit 200, and adjusts the voltage signal into a voltage sampling signal according to a sampling proportion; the sampling detection module 12 receives the voltage sampling signal, compares the voltage sampling signal with the reference voltage signal, and generates a detection result signal; the control module 13 receives the detection result signal, and if the detection result signal is that the voltage value represented by the voltage sampling signal is greater than or equal to the voltage value represented by the reference voltage signal, the control module 13 generates a sampling proportion control signal for reducing the sampling proportion and/or generates a reference voltage control signal for increasing the voltage value represented by the reference voltage signal; if the detection result signal meets the preset condition, the control module 13 controls to cut off the power supply to the load circuit 200, so as to implement the overvoltage protection processing.
In the embodiment, when effective overvoltage protection is realized, the overvoltage protection threshold is adjusted through the sampling proportion control signal and/or the reference voltage control signal, so that the power supply system can meet different output voltage grades, the design of the power supply system with multi-stage voltage output is greatly simplified, and the adaptability of the power supply system is improved.
Referring to fig. 15, an embodiment of the present invention further discloses a chip, which includes the above-mentioned overvoltage protection circuit; the chip is provided with a control signal output end Gate and a voltage sampling end ZCD.
In this embodiment, the control signal output terminal Gate and the voltage sampling terminal ZCD may be connected to the external load circuit 200, respectively.
As an embodiment of the chip applied to the flyback circuit, taking the circuit diagram shown in fig. 10 as an example, the chip may further be provided with a first sampling terminal CS and a second sampling terminal FB, the first sampling terminal CS may be connected to a source or a drain of the switching tube U1, the control signal output terminal Gate may be connected to a Gate of the switching tube U1, the voltage sampling terminal ZCD may be connected to the auxiliary coil La, and the second sampling terminal FB may be connected to the secondary coil Ls. Specifically, the control signal output terminal Gate may be configured to output a switch control signal to control the switching tube U1 to be turned on or off; the first sampling terminal CS may be used for sampling a current signal of a source or a drain of the switching converter; the second sampling terminal FB may be used for sampling the output voltage V of the secondary coil Lsout(ii) a The voltage sampling end ZCD can be used for sampling the output voltage V of the auxiliary coil LaAux。
The invention can also be applied to other power systems, and the application to the flyback circuit is only taken as an application scenario of the embodiment of the invention, and is not taken as a limitation to the invention.
The foregoing is a preferred embodiment of the present invention and is not intended to limit the scope of the invention in any way, and any feature disclosed in this specification (including the abstract and drawings) may be replaced by alternative features serving equivalent or similar purposes, unless expressly stated otherwise. That is, unless expressly stated otherwise, each feature is only an example of a generic series of equivalent or similar features.
Claims (9)
1. An overvoltage protection circuit, comprising: a sampling processing module (11) provided with a voltage signal input end, a sampling proportion control signal input end and a sampling signal output end; the voltage signal input end is used for acquiring a voltage signal input to an external load circuit (200), the sampling proportion control signal input end is used for acquiring a sampling proportion control signal, the sampling processing module (11) is configured to generate a voltage sampling signal according to the sampling proportion control signal and the voltage signal, the proportion between the voltage signal and the voltage sampling signal is consistent with the sampling proportion represented by the sampling proportion control signal, and the sampling signal output end is used for outputting the voltage sampling signal;
the sampling detection module (12) is connected with the sampling signal output end, and the sampling detection module (12) is used for acquiring a reference voltage signal and the voltage sampling signal, comparing the reference voltage signal with the voltage sampling signal and generating a detection result signal;
the control module (13) is respectively connected with the sampling proportion control signal input end and the sampling detection module (12), and the control module (13) is configured to generate the sampling proportion control signal according to the detection result signal and perform overvoltage protection processing on the load circuit (200) when the detection result signal meets a preset condition;
the sampling processing module (11) comprises a proportional adjustment unit comprising a first resistor (111), a second resistor (112) and a proportional switch (113); if the number of the proportion adjusting units is larger than or equal to two, at least two first resistors (111) are sequentially connected in series to form a first series circuit, at least one second resistor (112) is connected with at least one proportion switch (113) in series to form a second series circuit, and the number of the second series circuits is larger than or equal to two; the first series circuit is connected between the voltage signal input end and the sampling signal output end, and at least one second series circuit is connected between the second ends of the at least two first resistors (111) and a reference end (14).
2. An overvoltage protection circuit according to claim 1, wherein if the number of the proportional regulating units is one, a first end of the first resistor (111) is connected to the voltage signal input end, a common junction formed by a second end of the first resistor (111) and the second resistor (112) is connected to the sampling signal output end, and the second resistor (112) and the proportional switch (113) are connected in series between the common junction and the reference end (14); the proportional switch (113) is configured to adjust an on-off state based on the sampling proportional control signal; the resistance value of the first resistor (111) is greater than or equal to 0.
3. An overvoltage protection circuit according to claim 1, characterized in that said sampling detection module (12) is provided with a first input terminal, a second input terminal and an output terminal, said first input terminal being connected to said sampling signal output terminal, said output terminal being connected to said control module (13); the overvoltage protection circuit further comprises a reference voltage generation module (15), wherein the reference voltage generation module (15) is connected between the second input end and the control module (13); the control module (13) is further configured to output a reference voltage control signal according to the detection result signal, and the reference voltage generation module (15) is configured to output a reference voltage signal corresponding to the reference voltage control signal to the second input terminal.
4. An overvoltage protection circuit according to claim 1, characterized in that it further comprises a sampling control switch module (16), said sampling control switch module (16) being connected between said sampling processing module (11) and said sampling detection module (12); the sampling control switch module (16) is configured to conduct when a voltage value characterized by the voltage sampling signal is greater than zero.
5. An overvoltage protection circuit according to claim 4, characterized in that the overvoltage protection circuit further comprises a capacitance module (17), the common junction formed by the sampling control switch module (16) and the sampling detection module (12) is connected to a first end of the capacitance module (17), and a second end of the capacitance module (17) is connected to the reference terminal (14).
6. An overvoltage protection circuit according to any one of claims 1 to 5, characterized in that the overvoltage protection circuit is applied to a flyback circuit comprising a transformation module (21) provided with a primary coil (211), a secondary coil (212) and an auxiliary coil (213), and a switching converter (22) connected to the primary coil; the control module (13) is connected with the switching converter (22), and the voltage signal input end is connected with the auxiliary coil.
7. An overvoltage protection method applied to an overvoltage protection circuit according to any one of claims 1 to 6, wherein the overvoltage protection method comprises:
acquiring a detection result signal output by the sampling detection module (12), wherein the detection result signal is generated by the sampling detection module (12) according to a voltage sampling signal and a reference voltage signal;
generating a sampling proportion control signal according to the detection result signal;
sending the sampling proportion control signal to the sampling processing module (11) so that the sampling processing module (11) generates the voltage sampling signal according to the sampling proportion control signal and a voltage signal input to an external load circuit (200), wherein the proportion between the voltage signal and the voltage sampling signal is consistent with the sampling proportion represented by the sampling proportion control signal; and the number of the first and second groups,
and when the detection result signal meets the preset condition, carrying out overvoltage protection processing on the load circuit (200).
8. The method of claim 7, wherein generating a sampling ratio control signal according to the detection result signal comprises:
and if the voltage value represented by the voltage sampling signal is determined to be greater than or equal to the voltage value represented by the reference voltage signal according to the detection result signal, generating a sampling proportion control signal for reducing the sampling proportion, and/or generating a reference voltage control signal for increasing the voltage value represented by the reference voltage signal.
9. A chip comprising an overvoltage protection circuit as claimed in any one of claims 1 to 6.
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| CN116131219B (en) * | 2023-02-16 | 2023-06-30 | 恩赛半导体(成都)有限公司 | Overvoltage protection circuit and electronic device |
| CN116566024B (en) * | 2023-07-11 | 2023-09-29 | 成都利普芯微电子有限公司 | Battery protection system and lithium battery protection chip |
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| KR100809688B1 (en) * | 2006-03-31 | 2008-03-06 | 삼성전자주식회사 | Overvoltage protection control circuit and overvoltage protection control method |
| CN102005718B (en) * | 2009-08-31 | 2015-02-04 | 比亚迪股份有限公司 | Protector for electronic load and electronic load system |
| TW201240257A (en) * | 2011-03-17 | 2012-10-01 | Green Solution Tech Co Ltd | Transistor circuit with protecting function |
| CN202602326U (en) * | 2012-05-09 | 2012-12-12 | 杭州勇华车业有限公司 | Charger with over-voltage protection |
| CN203166467U (en) * | 2013-03-20 | 2013-08-28 | 向智勇 | Overvoltage protection circuit |
| CN106300246B (en) * | 2016-09-30 | 2018-08-28 | 英特格灵芯片(天津)有限公司 | Overvoltage crowbar |
| CN107681636A (en) * | 2017-11-22 | 2018-02-09 | 合肥惠科金扬科技有限公司 | A kind of overvoltage crowbar and Switching Power Supply |
| CN209419502U (en) * | 2018-12-29 | 2019-09-20 | 杰华特微电子（杭州）有限公司 | Power supply circuit, control circuit and Switching Power Supply |
| CN109586598A (en) * | 2018-12-29 | 2019-04-05 | 杰华特微电子（杭州）有限公司 | A kind of power supply circuit, control circuit and Switching Power Supply |
| CN209375187U (en) * | 2019-01-30 | 2019-09-10 | 深圳和而泰智能控制股份有限公司 | A kind of charging control circuit and charging unit |
| CN111654078A (en) * | 2020-06-04 | 2020-09-11 | 闻泰通讯股份有限公司 | Overvoltage protection circuit and overvoltage protector |
| CN213125601U (en) * | 2020-07-10 | 2021-05-04 | 深圳英集芯科技有限公司 | Overvoltage protection circuit for charging equipment interface |
| CN112952766B (en) * | 2020-12-24 | 2025-02-07 | 深圳市创芯微微电子有限公司 | Overvoltage protection module and adaptive power adapter |
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Address after: 518000, Building 101, Fuman Microelectronics Group Co., Ltd., Intersection of Renmin East Road and Shouhe Road, Jinsha Community, Kengzi Street, Pingshan District, Shenzhen City, Guangdong Province Patentee after: Fuman microelectronics Group Co.,Ltd. Country or region after: China Address before: 518048 1701, building 1, Shenzhen new generation industrial park, No. 136, Zhongkang Road, Meidu community, Meilin street, Futian District, Shenzhen, Guangdong Province Patentee before: Fuman microelectronics Group Co.,Ltd. Country or region before: China |
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