CN108123422B - Overvoltage protection circuit - Google Patents
Overvoltage protection circuit Download PDFInfo
- Publication number
- CN108123422B CN108123422B CN201611112579.6A CN201611112579A CN108123422B CN 108123422 B CN108123422 B CN 108123422B CN 201611112579 A CN201611112579 A CN 201611112579A CN 108123422 B CN108123422 B CN 108123422B
- Authority
- CN
- China
- Prior art keywords
- voltage
- coupled
- output
- signal
- power supply
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- 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
- H02H7/125—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 rectifiers
- H02H7/1252—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 rectifiers responsive to overvoltage in input or output, e.g. by load dump
-
- 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
- H02H7/125—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 rectifiers
- H02H7/1255—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 rectifiers responsive to internal faults, e.g. by monitoring ripple in output voltage
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
The invention provides an overvoltage protection circuit, which can distinguish whether an overvoltage state of output voltage of a switching type power supply device is caused by internal feedback failure or caused by an external power supply, can utilize the time difference of starting overvoltage protection to prevent a temporary and harmless external power supply from influencing the normal work of the switching type power supply device, and can also stop the operation of the switching type power supply device in real time to achieve protection when the internal feedback of the switching type power supply device fails.
Description
Technical Field
The present invention relates to an overvoltage protection circuit, and more particularly, to an overvoltage protection circuit suitable for a switching power supply device.
Background
A general Switching power supply (Switching power supply) uses an overvoltage protection circuit to control a Pulse Width Modulation (PWM) control circuit in the Switching power supply to stop outputting a PWM signal when an output terminal of the Switching power supply exhibits an overvoltage, so as to reduce an output voltage of the output terminal, thereby performing overvoltage protection on an internal circuit of the Switching power supply and an internal circuit of an external system of the output terminal, and preventing any one of the two from being damaged.
The output terminal will present overvoltage due to two conditions, one of which is caused by the failure of the internal circuit of the switching power supply device, such as the failure of the feedback circuit; the other is the back emf feedback caused by the external system, such as the external system with a motor, during deceleration. However, the conventional overvoltage protection circuit cannot distinguish the two circuits, so that when a user operates the external system normally to cause back electromotive force feedback, the conventional overvoltage protection circuit still controls the switching power supply device to immediately reduce the magnitude of the output voltage thereof to perform overvoltage protection, which causes the external system to be shut down and cannot be used normally, thereby causing a user to be troubled.
Disclosure of Invention
It is an object of the present invention to provide an overvoltage protection circuit which can distinguish between overvoltages caused by the two conditions and perform overvoltage protection in two different ways.
The invention provides an overvoltage protection circuit which is suitable for a switching type power supply device. The overvoltage protection circuit can distinguish whether the overvoltage state of the output voltage of the switching type power supply device is caused by internal feedback failure or caused by an external power supply, can utilize the time difference of starting the overvoltage protection to prevent the temporary and harmless external power supply from influencing the normal work of the switching type power supply device, and can also stop the action of the switching type power supply device in real time to achieve protection when the internal feedback of the switching type power supply device fails.
In order to make the aforementioned and other objects, features and advantages of the invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
Fig. 1 is a schematic diagram of a coupling relationship of an overvoltage protection circuit.
Detailed Description
Fig. 1 is a schematic diagram of a coupling relationship of an overvoltage protection circuit. In fig. 1, the switching Power supply apparatus 100 includes a noise filter 110, an ac-dc conversion circuit 120, a Power stage (Power stage)130, a transformer 140, a rectification circuit 150, an energy storage unit 160, a feedback circuit 170, and a signal isolation unit 180. The primary winding of the transformer 140 may be coupled to the input voltage VIN through the power stage 130, the ac-dc conversion circuit 120 and the noise filter 110 in sequence. The noise filter 110 may be an electromagnetic interference filter, and the user may decide whether to employ the noise filter 110.
In addition, the ac-dc conversion circuit 120 may be a bridge rectifier. The power stage 130 has a PWM control circuit 132 and a power transistor 134 as a switch. The power transistor 134 can be connected in series with the primary winding of the transformer 140, and whether to allow current to pass through the primary winding can be determined by controlling the On/off state (On/off state) of the power transistor 134. The PWM control circuit 132 is configured to generate a PWM signal and output the PWM signal to the control terminal of the power transistor 134, so as to control the switching frequency of the power transistor 134 between the on state and the off state.
The output of the secondary winding of the transformer 140 is rectified and filtered by the rectifying circuit 150 and the energy storage unit 160, respectively, and then is provided as the output voltage VOUT of the switching power supply 100 to an external system (not shown) from the output terminal 190. Furthermore, the rectifying circuit 150 and the energy storage unit 160 may be adopted according to design requirements. In addition, the signal isolation unit 180 may be an optical coupler (Photo coupler), which can transmit the feedback signal generated by the feedback circuit 170 to the PWM control circuit 132, so that the PWM control circuit 132 can adjust the duty cycle (duty cycle) of the PWM signal accordingly. Therefore, when the output terminal 190 of the switching power supply 100 exhibits an overvoltage, the PWM control circuit 132 can lower the output voltage VOUT according to the feedback signal transmitted from the signal isolation unit 180 for performing the overvoltage protection.
In addition, in fig. 1, the overvoltage protection circuit 200 includes a voltage sampling unit 210, a voltage sampling unit 220, an overvoltage detection unit 230, an overvoltage detection unit 250 and a signal isolation unit 280.
The overvoltage detection unit 230 is coupled to the output terminal 190 of the switching power supply device 100 and the signal isolation unit 280, the overvoltage detection unit 230 is configured to receive the output voltage VOUT at the output terminal 190, determine whether the output voltage VOUT exceeds a first predetermined value, and control the signal isolation unit 280 to output a reference voltage PGND to be conducted when the output voltage VOUT exceeds the first predetermined value, so that the signal isolation unit 280 generates the overvoltage protection trigger signal TRI correspondingly.
The overvoltage detection unit 250 is coupled to the output terminal 190 and the signal isolation unit 280, and the overvoltage detection unit 250 is configured to receive the output voltage VOUT at the output terminal 190, determine whether the output voltage VOUT exceeds a first default value, and control the signal isolation unit 280 to output the overvoltage protection trigger signal TRI after a default time if the output voltage VOUT exceeds the first default value.
The voltage sampling unit 210 is coupled to the output terminal 190 and the over-voltage detecting unit 230, and the voltage sampling unit 210 is configured to receive the output voltage VOUT at the output terminal 190, determine whether the magnitude of the output voltage VOUT exceeds a second predetermined value, and disable the over-voltage detecting unit 230 when the magnitude of the output voltage VOUT exceeds the second predetermined value.
The voltage sampling unit 220 is coupled to the voltage sampling unit 210 and one end of the secondary winding of the transformer, and is used to detect whether the voltage output by the secondary winding reaches a third default value, and when the voltage output by the secondary winding reaches the third default value, the voltage sampling unit 210 is disabled, and the overvoltage detection unit 230 can normally operate.
The signal isolation unit 280 is used for generating an over-voltage protection trigger signal TRI to the PWM control circuit 132 of the switching power supply device 100, so as to utilize the over-voltage protection trigger signal TRI to control the PWM control circuit 132 to stop generating the PWM signal.
Next, detailed embodiments of the rest of the overvoltage protection circuit 200 will be described. As shown in fig. 1, the voltage sampling unit 210 includes a voltage divider 215 and a voltage-controlled switch 216. The voltage divider 215 is coupled between the output terminal 190 of the switching power supply apparatus 100 and the reference voltage SGND, and generates a voltage dividing signal according to the voltage at the output terminal 190. The voltage divider circuit 215 may be a pair of resistors 215-1 and 215-2, wherein one terminal of the resistor 215-1 is coupled to the output terminal 190, one terminal of the resistor 215-2 is coupled to the other terminal of the resistor 215-1, and the other terminal of the resistor 215-2 is coupled to the reference voltage SGND. Both the impedance 215-1 and the impedance 215-2 may be resistors. The voltage-controlled switch 216 has a first terminal 216-1, a second terminal 216-2 and a reference terminal R, the first terminal 216-1 is coupled to the over-voltage detection unit 230, the second terminal 216-2 is coupled to the reference potential SGND, the reference terminal R receives the voltage-dividing signal, and the voltage-controlled switch 216 determines whether to turn on an electrical path between the first terminal 216-1 and the second terminal 216-2 according to a voltage level of the reference terminal R.
The voltage sampling unit 220 includes a diode 225, an energy storage unit, a voltage control switch 226, a voltage dividing circuit 227, and a voltage control switch 228. The anode of the diode 225 is coupled to one end of the secondary winding, and the energy storage unit 226 is coupled between the cathode of the diode 225 and the reference potential SGND. The voltage divider 227 is coupled between the cathode of the diode 225 and the reference voltage SGND, and generates a voltage dividing signal according to the voltage level stored in the energy storage unit 226. The voltage divider circuit 227 may be an impedance 227-1 and an impedance 227-2, wherein one terminal of the impedance 227-1 is coupled to the cathode of the diode 225, one terminal of the impedance 227-2 is coupled to the other terminal of the impedance 227-1, and the other terminal of the impedance 227-2 is coupled to the reference potential SGND. Both impedance 227-1 and impedance 227-2 may be resistors. The voltage-controlled switch 228 has a first terminal 228-1, a second terminal 228-2 and a reference terminal R, the first terminal 228-1 is coupled to the voltage sampling unit 210, the second terminal 228-2 is coupled to the reference potential SGND, the reference terminal R receives a voltage dividing signal of the voltage dividing circuit 227, and the voltage-controlled switch 228 determines whether to turn on an electrical path between the first terminal 228-1 and the second terminal 228-2 according to a voltage magnitude of the reference terminal R.
The overvoltage detection unit 230 includes a voltage divider 235, a comparator 236 and a diode 237. The voltage divider 235 is coupled between the output terminal 190 of the switching power supply 100 and the reference voltage SGND, the output terminal of the voltage divider 235 is coupled to the voltage sampling unit 210, and the voltage divider 235 outputs a voltage-divided signal according to the voltage magnitude of the output terminal of the switching power supply 100. The voltage divider 235 may be a pair of resistors 235-1 and 235-2, wherein one terminal of the resistor 235-1 is coupled to the output terminal 190, one terminal of the resistor 235-2 is coupled to the other terminal of the resistor 235-1, and the other terminal of the resistor 235-2 is coupled to the reference voltage SGND. The impedance 235-1 and the impedance 235-2 may be resistors. The comparator 236 has a positive input receiving the reference value Vref and a negative input receiving the divided signal of the voltage dividing circuit 235. The cathode of the diode 237 is coupled to the output of the comparator 236, and the anode thereof is coupled to the signal isolation unit 280.
The overvoltage detection unit 250 includes a voltage divider 255, a comparator 256, a diode 257, an energy storage unit 258, and a resistor 259. The voltage divider 255 is coupled between the output terminal 190 of the switching power supply 100 and the reference voltage SGND, and outputs a voltage-divided signal according to the magnitude of the output voltage VOUT. The voltage divider circuit 255 may comprise impedances 255-1 and 255-2, wherein one terminal of the impedance 255-1 is coupled to the output terminal 190, one terminal of the impedance 255-2 is coupled to the other terminal of the impedance 255-1, and the other terminal of the impedance 255-2 is coupled to the reference voltage SGND. The impedance 255-1 and the impedance 255-2 may be resistors. The positive input of the comparator 256 receives the reference value Vref, and the negative input thereof receives the divided signal of the voltage dividing circuit 255. The energy storage unit 258 receives the voltage-dividing signal at one end and is coupled to the reference voltage SGND at the other end. The cathode of the diode 257 is coupled to the output of the comparator 256, and the anode thereof is coupled to the signal isolation unit 280. An impedance 259 is further included between the energy storage unit 258 and the voltage divider circuit 255, one end of the impedance 259 is coupled to the output end of the voltage divider circuit 255, and the other end is coupled to the energy storage unit 258.
The signal isolation unit 280 includes a signal transmitting portion 284, a signal receiving portion 286 and an impedance 288. One end of the impedance 288 is coupled to the output terminal 190 of the switching power supply 100, one end of the signal transmitting portion 284 is coupled to the other end of the impedance 288, and the other end of the signal transmitting portion 284 is coupled to the anode of the diode 237 and the anode of the diode 257. The signal transmitting portion 284 is used to generate a coupling signal. One end of the signal receiving portion 286 is coupled to the PWM control circuit 132, and the other end is coupled to the reference potential PGND. The signal receiving portion 286 is used for receiving the coupling signal and generating the over-voltage protection trigger signal TRI accordingly. The signal transmitting portion 284 includes a light emitting portion, which is an optical coupler, for generating a light source as a coupling signal, and the signal receiving portion 286 includes a light receiving portion, which is an optical coupler, for receiving the coupling signal generated by the light source. The diode 282 may be used or not depending on the requirements.
Next, a detailed operation manner of the overvoltage protection circuit 200 will be described. Referring to fig. 1, the operation of the voltage protection circuit 200 is first described when the internal circuit of the switching power supply 100 fails and the output terminal 190 thereof exhibits an overvoltage.
As mentioned above, the overvoltage appearing at the output terminal 190 is caused by a failure of an internal circuit of the switching power supply apparatus 100, for example, a failure of the feedback circuit 170. Then the feedback circuit 170 cannot generate a feedback signal, so the PWM control circuit 132 cannot adjust the duty cycle of the PWM signal according to the feedback signal transmitted from the signal isolation unit 180, and thus the output voltage VOUT cannot be reduced, and the voltage output by the Secondary winding (Secondary winding) will be continuously increased.
When the voltage sampling unit 220 detects that the voltage outputted from the secondary winding reaches the third predetermined value, the first terminal 228-1 and the second terminal 228-2 of the voltage-controlled switch 228 are turned on, so that the terminal of the impedance 215-1 coupled to the impedance 215-2 of the voltage sampling unit 210 is pulled down to the ground potential, i.e., the reference terminal R of the voltage-controlled switch 216 is pulled down to the ground potential, and the voltage sampling unit 210 is disabled. At this time, the over-voltage detecting unit 230 and the over-voltage detecting unit 250 receive the output voltage VOUT through the voltage dividing circuit 235 and the voltage dividing circuit 255, respectively, and determine that the output voltage VOUT reaches the first default value, but the output of the comparator 256 is negatively saturated after a time delay due to the charging time of the energy storage unit 258. In contrast, the output of the comparator 236 can quickly exhibit negative saturation, so that the signal transmitting portion 284 can quickly generate the coupling signal through the path provided by the over-voltage detecting unit 230. After receiving the coupling signal, the signal receiving portion 286 may generate the over-voltage protection trigger signal TRI to the PWM control circuit 132, so that the PWM control circuit 132 may immediately reduce the output voltage VOUT by controlling the operation of the power transistor 134 for over-voltage protection.
Referring to fig. 1, the operation of the voltage protection circuit 200 will be described in the case that the external system causes the output terminal 190 to exhibit an overvoltage. In view of the above, the overvoltage appearing at the output terminal 190 is caused by the external system, such as the back emf feedback caused by the external system with a motor during deceleration. Therefore, the feedback circuit 170 will normally generate the feedback signal, so that the PWM control circuit 132 can adjust the duty cycle of the PWM signal according to the feedback signal transmitted from the signal isolation unit 180, thereby reducing the output voltage VOUT and lowering the voltage output by the Secondary winding (Secondary winding).
If the voltage outputted from the secondary winding decreases, the voltage sampling unit 220 detects that the voltage outputted from the secondary winding cannot reach the third default value. At this time, the reference terminal R of the voltage-controlled switch 216 receives the voltage-dividing signal through the voltage-dividing circuit 215, and when the voltage-controlled switch 216 turns on the electrical path between the first terminal 216-1 and the second terminal 216-2 according to the voltage of the reference terminal R, the end of the impedance 235-1 of the over-voltage detection unit 230 coupled to the impedance 235-2 is pulled down to the ground potential. I.e., the negative input of the comparator 236 is pulled down to ground potential, so that the output of the comparator 236 exhibits positive saturation and the diode 237 does not conduct. In addition, the comparator 256 of the over-voltage detection unit 250 receives the voltage-dividing signal through the voltage-dividing circuit 255, and the output of the comparator 256 exhibits negative saturation after a time delay due to the charging time of the energy storage unit 258, so that the diode 257 is turned on after a time delay. Due to the signalThe transmitting portion 284 must wait until the diode 257 is turned on to generate the coupling signal, so that the signal receiving portion 286 receives the coupling signal after delaying the period of time to generate the over-voltage protection trigger signal TRI to the PWM control circuit 132. Therefore, the PWM control circuit 132 can control the operation of the power transistor 134 to lower the output voltage VOUT after the delay time, so as to perform the over-voltage protection. In other words, in this case, the switching power supply 100 does not immediately perform the overvoltage protection, which results in the external system not operating normally, but performs the overvoltage protection after a delay. Of course, it should be understood by those skilled in the art that the delay time can be adjusted by changing the resistance of the impedance 259 or by changing the capacitance of the energy storage unit 258.
In summary, in the overvoltage protection circuit of the invention, the determination result of the voltage sampling unit can be used to reflect whether the output terminal of the switching power supply device exhibits an overvoltage due to a failure of an internal circuit of the switching power supply device or due to an external system. Therefore, the voltage sampling unit can provide different paths so as to further enable the signal isolation unit to generate the overvoltage protection trigger signal with different time under two different overvoltage conditions. By means of such control, the overvoltage protection circuit of the invention can immediately generate the overvoltage protection trigger signal to control the switching type power supply device to perform overvoltage protection when the internal circuit of the switching type power supply device fails, and delay the time of generating the overvoltage protection trigger signal when the external system causes overvoltage, so that the switching type power supply device cannot immediately perform overvoltage protection to cause the external system to fail to operate normally.
Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (5)
1. An overvoltage protection circuit suitable for a switching power supply device, comprising:
a signal isolation unit for generating an over-voltage protection trigger signal to a pulse width modulation control circuit of the switching power supply device, so as to control the pulse width modulation control circuit to stop generating a pulse width modulation signal by using the over-voltage protection trigger signal;
a first overvoltage detection unit coupled to an output terminal of the switching power supply device and the signal isolation unit, the first overvoltage detection unit being configured to receive an output voltage at the output terminal and determine whether the output voltage exceeds a first default value, and if so, control the signal isolation unit to output a reference voltage to conduct, so that the signal isolation unit correspondingly generates the overvoltage protection trigger signal;
a second overvoltage detection unit coupled to the output terminal and the signal isolation unit, the second overvoltage detection unit being configured to receive the output voltage at the output terminal, determine whether the output voltage exceeds the first default value, and control the signal isolation unit to output the overvoltage protection trigger signal after a default time if the output voltage exceeds the first default value;
a first voltage sampling unit coupled to the output terminal and the first overvoltage detection unit, the first voltage sampling unit being configured to receive the output voltage at the output terminal and determine whether the output voltage exceeds a second default value, and disable the first overvoltage detection unit if the output voltage exceeds the second default value; and
a second voltage sampling unit coupled to the first voltage sampling unit and one end of a secondary side coil of a transformer for detecting whether the voltage output by the secondary side coil reaches a third default value, and when the voltage output by the secondary side coil reaches the third default value, the first voltage sampling unit is disabled, and the first overvoltage detection unit can normally work.
2. The overvoltage protection circuit of claim 1, wherein said first voltage sampling unit comprises:
a voltage dividing circuit coupled between the output terminal and the reference potential to generate a voltage dividing signal; and
the voltage-controlled switch is provided with a first end, a second end and a reference end, wherein the reference end receives the voltage division signal, and the voltage-controlled switch determines whether to conduct an electric path between the first end and the second end according to the voltage of the reference end.
3. The overvoltage protection circuit of claim 1, wherein said second voltage sampling unit comprises:
a diode with its anode coupled to one end of the secondary winding;
an energy storage unit coupled between the cathode of the diode and the reference potential;
a voltage dividing circuit coupled between the cathode of the diode and the reference potential and generating a voltage dividing signal according to the voltage magnitude stored in the energy storage unit; and
the voltage-controlled switch is provided with a first end, a second end and a reference end, wherein the reference end receives the voltage division signal, and the voltage-controlled switch determines whether to conduct an electric path between the first end and the second end according to the voltage of the reference end.
4. The overvoltage protection circuit of claim 1, wherein said first overvoltage detection unit comprises:
a voltage dividing circuit, coupled between the output terminal of the switching power supply device and the reference potential, the output terminal of the voltage dividing circuit being coupled to the first voltage sampling unit, and the voltage dividing circuit outputting a voltage dividing signal according to the voltage magnitude of the output terminal of the switching power supply device;
a comparator, whose positive input terminal receives a reference and negative input terminal receives the voltage-dividing signal; and
a diode, the cathode of which is coupled to the output of the comparator, and the anode of which is coupled to the signal isolation unit.
5. The overvoltage protection circuit of claim 1, wherein said second overvoltage detection unit comprises:
a voltage dividing circuit coupled between the output terminal of the switching power supply device and the reference potential and outputting a voltage dividing signal according to the voltage of the output terminal;
a first impedance, one end of which is coupled to the output end of the voltage dividing circuit;
a comparator, whose positive input end receives a reference value and negative input end receives the voltage-dividing signal;
a diode, the cathode of which is coupled with the output of the comparator, and the anode of which is coupled with the signal isolation unit; and
one end of the energy storage unit is coupled with the other end of the first impedance, and the other end of the energy storage unit is coupled with the reference potential.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611112579.6A CN108123422B (en) | 2016-11-30 | 2016-11-30 | Overvoltage protection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611112579.6A CN108123422B (en) | 2016-11-30 | 2016-11-30 | Overvoltage protection circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108123422A CN108123422A (en) | 2018-06-05 |
| CN108123422B true CN108123422B (en) | 2019-12-27 |
Family
ID=62226446
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201611112579.6A Active CN108123422B (en) | 2016-11-30 | 2016-11-30 | Overvoltage protection circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108123422B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6525948B2 (en) * | 2000-12-19 | 2003-02-25 | Delta Electronics Inc. | Apparatus and method for the detection of circuit irregularities and for circuit protection of a power supply |
| CN102340129A (en) * | 2010-07-23 | 2012-02-01 | 中国长城计算机深圳股份有限公司 | Switching power supply and overvoltage protection circuit thereof |
| CN202633910U (en) * | 2012-05-04 | 2012-12-26 | 福建捷联电子有限公司 | Power supply module with overvoltage protection function |
| CN103326325A (en) * | 2013-06-05 | 2013-09-25 | 广州凯盛电子科技有限公司 | Short-circuit and low-voltage protective circuit of output of switching power source |
| CN103701324A (en) * | 2013-12-12 | 2014-04-02 | 深圳市英威腾交通技术有限公司 | Emergency starting power supply circuit |
| CN205647278U (en) * | 2015-12-25 | 2016-10-12 | 安徽工程大学 | Switch power supply protection circuit |
-
2016
- 2016-11-30 CN CN201611112579.6A patent/CN108123422B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6525948B2 (en) * | 2000-12-19 | 2003-02-25 | Delta Electronics Inc. | Apparatus and method for the detection of circuit irregularities and for circuit protection of a power supply |
| CN102340129A (en) * | 2010-07-23 | 2012-02-01 | 中国长城计算机深圳股份有限公司 | Switching power supply and overvoltage protection circuit thereof |
| CN202633910U (en) * | 2012-05-04 | 2012-12-26 | 福建捷联电子有限公司 | Power supply module with overvoltage protection function |
| CN103326325A (en) * | 2013-06-05 | 2013-09-25 | 广州凯盛电子科技有限公司 | Short-circuit and low-voltage protective circuit of output of switching power source |
| CN103701324A (en) * | 2013-12-12 | 2014-04-02 | 深圳市英威腾交通技术有限公司 | Emergency starting power supply circuit |
| CN205647278U (en) * | 2015-12-25 | 2016-10-12 | 安徽工程大学 | Switch power supply protection circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108123422A (en) | 2018-06-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9099929B2 (en) | Power converting device and synchronous rectifier control circuit | |
| TWI481140B (en) | Switching power supply circuit and electronic equipment with protection function | |
| US20140119065A1 (en) | Switching power-supply device | |
| US9318961B2 (en) | Switching power-supply device | |
| US9350251B2 (en) | Power conversion apparatus and over power protection method thereof | |
| JP2015070750A (en) | Power conversion device | |
| TW201316659A (en) | Power supply | |
| US9954457B2 (en) | Overvoltage protection circuit | |
| TWI614975B (en) | Over-voltage protection circuit | |
| US9608434B2 (en) | Inverter apparatus having primary-side and secondary-side driver circuits driven by respective DC/DC converters and control method thereof | |
| CN108123429B (en) | Overvoltage protection circuit | |
| TWI625032B (en) | Low phase surge protection device | |
| CN108123422B (en) | Overvoltage protection circuit | |
| CN107819398B (en) | Overvoltage protection circuit | |
| CN107819399B (en) | Overvoltage protection circuit | |
| KR20150070590A (en) | Circuit for driving synchronous rectifier and power supply apparatus including the same | |
| JP2009081901A (en) | Device for preventing excessive voltage | |
| US10923903B2 (en) | Low phase surge protection device | |
| TWI612762B (en) | Over-voltage protection circuit | |
| JP5478347B2 (en) | Light source lighting device and lighting fixture | |
| RU149858U1 (en) | VOLTAGE RETURN CONVERTER WITH PROTECTIVE CIRCUIT DURING INPUT VOLTAGE | |
| TWI577116B (en) | Over-voltage protection circuit | |
| KR200148186Y1 (en) | Power supply apparatus | |
| KR20150115214A (en) | Over voltage protective switch mode power supply | |
| JP3097403U (en) | Switching power supply |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |