CN209805407U - Short-circuit protection circuit - Google Patents
Short-circuit protection circuit Download PDFInfo
- Publication number
- CN209805407U CN209805407U CN201920351986.5U CN201920351986U CN209805407U CN 209805407 U CN209805407 U CN 209805407U CN 201920351986 U CN201920351986 U CN 201920351986U CN 209805407 U CN209805407 U CN 209805407U
- Authority
- CN
- China
- Prior art keywords
- resistor
- module
- circuit
- load
- short
- 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
Landscapes
- Protection Of Static Devices (AREA)
Abstract
the utility model relates to a short-circuit protection circuit. The method comprises the following steps: the second input end of the switch control module is connected with the output end of the delay detection judging module; the time delay detection module is used for receiving the control signal output by the time delay detection judging module and connecting or disconnecting the power supply and the load according to the control signal; the output end of the voltage stabilizing module is connected with the delay detection judging module; the time delay detection and judgment module is used for providing reference voltage for the time delay detection and judgment module; the delay detection judging module is connected between the switch control module and the load; the control circuit is used for detecting the load voltage, comparing the load voltage with the reference voltage to generate a control signal, and transmitting the control signal to the switch control module after delaying the preset time. The circuit judges whether short circuit occurs or not by adopting a load end sampling mode, namely the on-off control of the short-circuit protection circuit is only related to the end voltage of the load, so that the stable protection state of the protection circuit after the load short circuit is realized, and the short-circuit protection circuit recovers the normal power supply of the load after the load short circuit is eliminated.
Description
Technical Field
The utility model relates to an electronic circuit's circuit protection technical field especially relates to a short-circuit protection circuit.
background
The current short-circuit protection circuit generally compares the voltage output by the power supply with the acquired reference voltage to judge whether the short circuit occurs, if the short circuit occurs, the voltage output by the power supply is reduced to control the disconnection of the power supply and the load, after the protection circuit is enabled, the voltage output by the power supply is recovered to be normal, the short-circuit protection circuit recovers the power supply of the load, then the short-circuit protection is triggered, and the short-circuit protection is circulated until the short circuit of the load is eliminated, and the load can recover to work normally.
However, after the protection circuit is enabled, the output voltage of the power supply returns to normal, so that the short-circuit protection circuit returns to the load power supply, which causes the control of the short-circuit protection circuit to be always in a dynamic state of switching cycle, and the stability of the circuit and the damage of the short-circuit protection circuit are large.
SUMMERY OF THE UTILITY MODEL
Therefore, it is necessary to provide a short-circuit protection circuit for solving the problems that the short-circuit protection circuit is in a switching cycle state and the power supply cannot be normally recovered after the short-circuit protection circuit is locked.
a short-circuit protection circuit, comprising: the switch control module and the voltage stabilizing module detect and judge the module in a time delay way; the switch control module is provided with a first input end and a second input end, the first input end is connected with a power supply, the second input end is connected with the output end of the delay detection judging module, and the output end of the switch control module is connected with a load; the switch control module receives the control signal output by the delay detection and judgment module and connects or disconnects a power supply and a load according to the control signal; the input end of the voltage stabilizing module is connected with the power supply, and the output end of the voltage stabilizing module is connected with the delay detection judging module; the voltage stabilizing module provides reference voltage for the delay detection judging module; the delay detection judging module is connected between the switch control module and the load; the control circuit is used for detecting the load voltage, comparing the load voltage with the reference voltage to generate a control signal, and transmitting the control signal to the switch control module after delaying preset time.
in one embodiment, the delay detection and determination module includes: the short circuit detection device comprises a short circuit judgment module and a detection module; the input end of the detection module is connected between the switch control module and the load, and the output end of the detection module is connected with the short circuit judgment module; the detection module detects load voltage, delays the load voltage for a first preset time and then transmits the load voltage to the short circuit judgment module; the first input end of the short circuit judging module is connected with the voltage stabilizing module, the second input end of the short circuit judging module is connected with the detecting module, and the output end of the short circuit judging module is connected with the switch control module; the short circuit judging module receives the reference voltage transmitted by the voltage stabilizing module and the load voltage transmitted by the detecting module, compares the load voltage with the reference voltage to generate a control signal, and transmits the control signal to the switch control module after delaying for a second preset time.
in one embodiment, at least one of the first preset time and the second preset time is greater than zero.
In one embodiment, the switch control module comprises: the MOS transistor comprises a first resistor, a second resistor, a first capacitor and a first MOS transistor; the source level of the first MOS tube is connected with a power supply, the drain electrode of the first MOS tube is connected with the load, the grid electrode of the first MOS tube is connected with the output end of the short-circuit judging module through the second resistor, and the first resistor and the first capacitor are connected in parallel between the source level of the first MOS tube and the grid electrode of the first MOS tube.
In one embodiment, the short circuit determining module includes: the circuit comprises a first operational amplifier, a third resistor, a fourth resistor and a fifth resistor; the output end of the first operational amplifier is connected with the second resistor, the inverting input end of the first operational amplifier is connected with the output end of the detection module, and the connecting point of the inverting input end of the first operational amplifier and the detection module is grounded through a third resistor; the non-inverting input end of the first operational amplifier is connected with the voltage stabilizing module through a fifth resistor, and the connection point of the non-inverting input end of the first operational amplifier and the fifth resistor is grounded through a fourth resistor.
In one embodiment, the detection module comprises: a sixth resistor, a seventh resistor and a second capacitor; one end of the seventh resistor is connected between the switch control module and the load, and the other end of the seventh resistor is connected with the inverting input end of the first operational amplifier; one end of the sixth resistor is connected with the voltage stabilizing module, and the other end of the sixth resistor is connected with the inverting input end of the first operational amplifier; and a second capacitor is connected in parallel at two ends of the sixth resistor.
in one embodiment, the switch control module comprises: the eighth resistor, the ninth resistor, the third capacitor and the second MOS tube; the source of the second MOS tube is connected with a power supply, the drain of the second MOS tube is connected with the load, and the grid of the second MOS tube is connected with the output end of the short-circuit judging module through the ninth resistor; one end of the eighth resistor is connected with the voltage stabilizing module, and the other end of the eighth resistor is connected with a connection point of the grid of the second MOS tube and the ninth resistor; one end of the third capacitor is connected with a connection point of the grid electrode of the second MOS tube and the ninth resistor, and the other end of the third capacitor is grounded.
In one embodiment, the short circuit determining module includes: a second operational amplifier, a tenth resistor, an eleventh resistor, and a twelfth resistor; the output end of the second operational amplifier is connected with the ninth resistor, the non-inverting input end of the second operational amplifier is connected with the output end of the detection module, and the connecting point of the non-inverting input end of the second operational amplifier and the detection module is grounded through a tenth resistor; the reverse input end of the second operational amplifier is connected with the voltage stabilizing module through a twelfth resistor, and the connection point of the reverse input end of the second operational amplifier and the twelfth resistor is grounded through an eleventh resistor.
In one embodiment, the detection module comprises: a thirteenth resistor, a fourteenth resistor, and a fourth capacitor; one end of the fourteenth resistor is connected between the switch control module and the load, and the other end of the fourteenth resistor is connected with the non-inverting input end of the second operational amplifier; one end of the thirteenth resistor is connected with the voltage stabilizing module, and the other end of the thirteenth resistor is connected with the non-inverting input end of the second operational amplifier; and a fourth capacitor is connected in parallel with two ends of the thirteenth resistor.
In one embodiment, the voltage stabilizing module comprises a voltage conversion chip.
The short-circuit protection circuit is provided with a switch control module, a voltage stabilizing module and a delay detection judging module, wherein the delay detection judging module is connected between the switch control module and a load and used for detecting the voltage of the load and comparing the voltage of the load with the reference voltage transmitted by the voltage stabilizing module to obtain a control signal so as to control the connection or disconnection of the switch control module. The circuit judges whether short circuit occurs or not by adopting a load end sampling mode, namely the on-off control of the short-circuit protection circuit is only related to the end voltage of the load, so that the stable protection state of the protection circuit after the load short circuit is realized, and the short-circuit protection circuit recovers the normal power supply of the load after the load short circuit is eliminated.
Drawings
FIG. 1 is a schematic diagram of an embodiment of a short protection circuit;
FIG. 2 is a circuit diagram of a short-circuit protection circuit in one embodiment;
Fig. 3 is a circuit diagram of a short-circuit protection circuit in another embodiment.
reference numerals: the circuit comprises a switch control module 100, a voltage stabilizing module 200, a delay detection judging module 300, a short circuit judging module 310, a detection module 320, a power supply 400, a load 500, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a first MOS tube Q1, a second MOS tube Q2, a first operational amplifier U2 and a second operational amplifier U3.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and 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.
Referring to fig. 1, fig. 1 is a schematic structural diagram of a short-circuit protection circuit according to an embodiment.
As shown in fig. 1, a short-circuit protection circuit includes: the switch control module 100, the voltage stabilizing module 200 and the delay detection judging module 300; the switch control module 100 has a first input end and a second input end, the first input end is connected with the power supply 400, the second input end is connected with the output end of the delay detection and judgment module 300, and the output end of the switch control module 100 is connected with the load 500; the switch control module 100 receives the control signal output by the delay detection and judgment module 300, and connects or disconnects the power supply 400 and the load 500 according to the control signal; the input end of the voltage stabilizing module 200 is connected with the power supply 400, and the output end is connected with the delay detection judging module 300; the voltage stabilizing module 200 provides a reference voltage for the delay detection and judgment module 300; the delay detection and judgment module 300 is connected between the switch control module 100 and the load 500; the switching control module 100 is configured to detect a load voltage, compare the load voltage with the reference voltage to generate a control signal, and transmit the control signal to the switching control module 100 after delaying a preset time.
In one embodiment, the delay detection determining module 300 includes: a short circuit determination module 310 and a detection module 320; the input end of the detection module 320 is connected between the switch control module 100 and the load 500, and the output end is connected with the short circuit judgment module 310; the detection module 320 detects a load voltage, and transmits the load voltage to the short circuit determination module 310 after delaying the load voltage for a first preset time; a first input end of the short circuit judgment module 310 is connected to the voltage stabilization module 200, a second input end thereof is connected to the detection module 320, and an output end thereof is connected to the switch control module 100; the short circuit determining module 310 receives the reference voltage transmitted by the voltage stabilizing module 200 and the load voltage transmitted by the detecting module 320, compares the load voltage with the reference voltage to generate a control signal, and transmits the control signal to the switch control module 100 after delaying a second preset time. At least one of the first preset time and the second preset time is greater than zero.
Specifically, the voltage at the load end is detected by the detecting module 320, and the load voltage is transmitted to the short circuit determining module 310 after delaying for a first preset time. The voltage stabilizing module 200 provides the reference voltage to the short circuit determining module 310, and the voltage stabilizing module 200 is further configured to provide the driving voltage to the switch control module 100 and the detecting module 320, wherein the voltage stabilizing module 200 includes: and a voltage conversion chip. The short circuit determination module 310 compares the load voltage with the reference voltage to determine whether the load 500 is in a short circuit state, generates a control signal according to whether the load is in a short circuit state, and transmits the control signal to the switch control module 100. The switch control module 100 controls the power supply 400 and the load 500 to be connected or controls the power supply 400 and the load 500 to be disconnected according to the received control module. Thereby achieving the purpose of short-circuit protection. The control signal may be delayed for a second preset time and then transmitted to the switch control module 100 after the short circuit determining module 310 generates the control signal. The purpose of the delay is to enable the load voltage to change for a preset time, and then to affect the short circuit determination module 310 to output a control signal to the switch control module 100. It can be understood that the requirement can be met only by setting the first preset time, the requirement can also be met only by setting the second preset time, and the requirement can also be met by setting the first preset time and the second preset time simultaneously. In the embodiment, whether short circuit occurs is judged by sampling at the load end, the on-off control of the short-circuit protection circuit is designed to be only related to the load voltage, so that the short-circuit protection circuit can keep a stable protection state after the load 500 is short circuited, and the protection circuit recovers normal power supply of the load 500 after the short circuit of the load 500 is eliminated.
referring to fig. 2 in one embodiment, fig. 2 is a circuit diagram of a short-circuit protection circuit in one embodiment.
as shown in fig. 2, the switch control module 100 includes: the circuit comprises a first resistor R1, a second resistor R2, a first capacitor C1 and a first MOS transistor Q1; the source of the first MOS transistor Q1 is connected to the power supply 400, the drain of the first MOS transistor Q1 is connected to the load, the gate of the first MOS transistor Q1 is connected to the output of the short-circuit determination module 310 through the second resistor R2, and the first resistor R1 and the first capacitor C1 are connected in parallel between the source of the first MOS transistor Q1 and the gate of the first MOS transistor Q1. The short circuit determination module 310 includes: a first operational amplifier U2, a third resistor R3, a fourth resistor R4 and a fifth resistor R5; the output end of the first operational amplifier U2 is connected to the second resistor R2, the inverting input end of the first operational amplifier U2 is connected to the output end of the detection module 320, and the connection point of the inverting input end of the first operational amplifier U2 and the detection module 320 is grounded through a third resistor R3; the non-inverting input terminal of the first operational amplifier U2 is connected to the voltage stabilizing module 200 through a fifth resistor R5, and a connection point between the non-inverting input terminal of the first operational amplifier U2 and the fifth resistor R5 is grounded through a fourth resistor R4. The detection module 320 includes: a sixth resistor R6, a seventh resistor R7 and a second capacitor C2; one end of the seventh resistor R7 is connected between the switch control module 100 and the load, and the other end of the seventh resistor R7 is connected to the inverting input terminal of the first operational amplifier U2; one end of the sixth resistor R6 is connected to the voltage regulator module 200, and the other end of the sixth resistor R6 is connected to the inverting input terminal of the first operational amplifier U2; and a second capacitor C2 is connected in parallel with two ends of the sixth resistor R6.
specifically, the voltage stabilizing module 200 is a voltage converting chip, converts the output voltage of the power supply 400 into a reference voltage, the reference voltage is divided by the fifth resistor R5/the fourth resistor R4 and divided by the sixth resistor R6/the third resistor R3 to generate two reference voltages of the comparator, the load voltage is superimposed on the divided voltage of the sixth resistor R6/the third resistor R3 by the seventh resistor R7 to serve as an inverting input terminal of the comparator, and the first operational amplifier U2 serves as the comparator to output a control signal to the first MOS transistor Q1, where the first MOS transistor is a P-type MOS transistor. The switch of the first MOS transistor Q1 is used for realizing normal power supply and short-circuit protection of the load.
More specifically, after the power supply is initially powered up, the load anode is floating, and the seventh resistor R7 is negligible. The voltage division value of the sixth resistor R6 and the third resistor R3 is greater than the voltage division value of the fifth resistor R5 and the fourth resistor R4, so the first operational amplifier U2 outputs a control signal to turn on the first MOS transistor Q1. When the first MOS transistor Q1 is turned on, the load anode starts to charge, the level state starts to rise from the low level, at this time, the load is approximately short-circuited, and the seventh resistor R7 and the load connection end are approximately grounded. The normal voltage division value of the sixth resistor R6, the seventh resistor R7 and the third resistor R3 is smaller than the voltage division value of the fifth resistor R5 and the fourth resistor R4, which can be understood as triggering short-circuit protection. However, due to the existence of the second capacitor C2, the potential difference between the two ends of the capacitor does not change abruptly, so the voltage at the reverse input end of the first operational amplifier U2 is still greater than that at the forward input end, and the first MOS transistor Q1 continues to be kept conducting. During the charging period of the second capacitor C2, the voltage of the positive electrode of the load rises to a certain voltage, and when the normal voltage division value of the sixth resistor R6, the seventh resistor R7 and the third resistor R3 is greater than the voltage division value of the fifth resistor R5 and the fourth resistor R4, the control signal output by the first operational amplifier U2 keeps the first MOS transistor Q1 turned on until the load voltage is equal to the output voltage of the power supply, so that the load works normally. When a load short circuit occurs, the normal voltage division value of the sixth resistor R6, the seventh resistor R7 and the third resistor R3 is smaller than the voltage division value of the fifth resistor R5 and the fourth resistor R4, after the second capacitor C2 is charged, the short circuit state is not eliminated, the first operational amplifier U2 outputs a control signal to control the first MOS transistor Q1 to be disconnected for short circuit protection, and a stable short circuit protection state is always maintained before the load short circuit state is eliminated. When the load short-circuit state is eliminated, the anode of the load is suspended, the second capacitor C2 starts to discharge, and the normal voltage division value of the sixth resistor R6 and the third resistor R3 is greater than the voltage division value of the fifth resistor R5 and the fourth resistor R4, so the first operational amplifier U2 outputs a control signal to control the conduction of the first MOS transistor Q1, but since the potential difference between the two ends of the first capacitor C1 cannot suddenly change, the first MOS transistor Q1 is not actually conducted before the first capacitor C1 is charged, and in the charging process of the first capacitor C1, the second capacitor C2 finishes discharging. When the first MOS transistor Q1 is turned on, a power-up process is performed to normally supply power to the load. The first capacitor C1 is used to provide the second capacitor C2 with a sufficient discharge time. The key to distinguish between a load power-up and a load short-circuit is the charging time of the second capacitor C2. If the load is recovered to be normal after short circuit in the connection state, the load is electrified to be approximately short-circuited, and the short-circuit protection circuit has certain uncertainty in the working state due to insufficient discharge of the second capacitor C2; if the short-circuit protection circuit is applied to a scene that the load needs to be removed for repair after the load is short-circuited, the first capacitor C1 may not be used, because the second capacitor C2 has sufficient time to discharge when the load is removed.
In one embodiment, please refer to fig. 3, fig. 3 is a circuit diagram of a short-circuit protection circuit in another embodiment.
As shown in fig. 3, the switching control module 100 includes: an eighth resistor R8, a ninth resistor R9, a third capacitor C3 and a second MOS transistor Q2; the source of the second MOS transistor Q2 is connected to the power supply, the drain of the second MOS transistor Q2 is connected to the load, and the gate of the second MOS transistor Q2 is connected to the output of the short circuit determining module 310 through the ninth resistor R9; one end of the eighth resistor R8 is connected to the voltage regulator module 200, and the other end of the eighth resistor R8 is connected to a connection point between the gate of the second MOS transistor Q2 and the ninth resistor R9; one end of the third capacitor C3 is connected to a connection point between the gate of the second MOS transistor Q2 and the ninth resistor R9, and the other end of the third capacitor C3 is grounded. The short circuit determination module 310 includes: a second operational amplifier U3, a tenth resistor R10, an eleventh resistor R11, and a twelfth resistor R12; the output end of the second operational amplifier U3 is connected to the ninth resistor R9, the non-inverting input end of the second operational amplifier U3 is connected to the output end of the detection module 320, and the connection point of the non-inverting input end of the second operational amplifier U3 and the detection module 320 is grounded through a tenth resistor R10; the inverting input terminal of the second operational amplifier U3 is connected to the voltage stabilizing module 200 through a twelfth resistor R12, and the connection point of the inverting input terminal of the second operational amplifier U3 and the twelfth resistor R12 is grounded through an eleventh resistor R11. The detection module 320 includes: a thirteenth resistor R13, a fourteenth resistor R14, and a fourth capacitor C4; one end of the fourteenth resistor R14 is connected between the switch control module 100 and the load, and the other end of the fourteenth resistor R14 is connected to the non-inverting input terminal of the second operational amplifier U3; one end of the thirteenth resistor R13 is connected to the voltage stabilizing module 200, and the other end of the thirteenth resistor R13 is connected to the non-inverting input terminal of the second operational amplifier U3; a fourth capacitor C4 is connected in parallel to two ends of the thirteenth resistor R13.
Specifically, the voltage stabilizing module 200 is a voltage converting chip, converts the output voltage of the power supply into a reference voltage, the reference voltage is divided by a twelfth resistor R12/an eleventh resistor R11 and divided by a thirteenth resistor R13/a tenth resistor R10 to generate two reference voltages of a comparator, the load voltage is superimposed on the divided voltage of a thirteenth resistor R13/a tenth resistor R10 by a fourteenth resistor R14 to serve as a non-inverting input terminal of the comparator, the second operational amplifier U3 serves as the comparator to output a control signal to the second MOS transistor Q2, wherein the second MOS transistor Q2 is an N-type MOS transistor. The switch of the second MOS transistor Q2 is used for realizing normal power supply and short-circuit protection of the load.
More specifically, after the power supply is initially powered up, the load anode is floating, and the fourteenth resistor R14 can be ignored. The voltage division value of the thirteenth resistor R13 and the tenth resistor R10 is greater than the voltage division value of the twelfth resistor R12 and the eleventh resistor R11, so the second operational amplifier U3 outputs a control signal to turn on the second MOS transistor Q2. When the second MOS transistor Q2 is turned on, the load anode starts to charge, the level state starts to increase from the low level, at this time, the load is approximately short-circuited, and the fourteenth resistor R14 and the load connection end are approximately grounded. The normal voltage dividing value of the thirteenth resistor R13, the fourteenth resistor R14 and the tenth resistor R10 is smaller than the voltage dividing value of the twelfth resistor R12 and the eleventh resistor R11, which can be understood as triggering short-circuit protection. However, due to the existence of the fourth capacitor C4, the potential difference between the two ends of the capacitor does not change suddenly, so that the voltage at the non-inverting input end of the second operational amplifier U3 is still greater than that at the inverting input end, and the second MOS transistor Q2 continues to be kept conducting. During the charging period of the fourth capacitor C4, the voltage of the positive electrode of the load rises to a certain voltage, and when the normal divided voltage value of the thirteenth resistor R13, the fourteenth resistor R14 and the tenth resistor R10 is greater than the divided voltage value of the twelfth resistor R12 and the eleventh resistor R11, the control signal output by the second operational amplifier U3 keeps the second MOS transistor Q2 turned on until the load voltage is equal to the output voltage of the power supply, so that the load works normally. When a load short circuit occurs, the normal voltage division value of the thirteenth resistor R13, the fourteenth resistor R14 and the tenth resistor R10 is smaller than the voltage division value of the twelfth resistor R12 and the eleventh resistor R11, after the fourth capacitor C4 is charged, the short circuit state is not eliminated, the second operational amplifier U3 outputs a control signal to control the second MOS transistor Q2 to be disconnected for short circuit protection, and a stable short circuit protection state is always maintained before the load short circuit state is eliminated. When the load short-circuit state is eliminated, the anode of the load is suspended, the fourth capacitor C4 starts to discharge, and the normal voltage division value of the thirteenth resistor R13 and the tenth resistor R10 is greater than the voltage division value of the twelfth resistor R12 and the eleventh resistor R11, so the second operational amplifier U3 outputs a control signal to control the conduction of the second MOS transistor Q2, but since the potential difference between the two ends of the third capacitor C3 cannot suddenly change, the second MOS transistor Q2 is not actually conducted before the third capacitor C3 is charged, and the fourth capacitor C4 finishes discharging in the charging process of the third capacitor C3. When the second MOS transistor Q2 is turned on, a power-up process is performed to normally supply power to the load. The third capacitor C3 is used to provide the fourth capacitor C4 with a sufficient discharge time. The key to distinguish between a load power-up and a load short-circuit is the charging time of the fourth capacitor C4. If the load is recovered to be normal after short circuit in the connection state, the load is electrified to be approximately short-circuited, and the working state of the short-circuit protection circuit has certain uncertainty due to insufficient discharge of the fourth capacitor C4; if the short-circuit protection circuit is applied to a scene that the load needs to be removed for repair after the load is short-circuited, the third capacitor C3 is not needed, because the fourth capacitor C4 has enough time to discharge when the load is removed.
the short-circuit protection circuit is provided with a switch control module, a voltage stabilizing module and a delay detection judging module, wherein the second input end of the delay detection judging module is connected between the switch control module and a load and used for detecting the voltage of the load and comparing the voltage of the load with the reference voltage transmitted by the voltage stabilizing module to obtain a control signal so as to control the connection or disconnection of the switch control module. The circuit judges whether short circuit occurs or not by adopting a load end sampling mode, namely the on-off control of the short-circuit protection circuit is only related to the end voltage of the load, so that the stable protection state of the protection circuit after the load short circuit is realized, and the short-circuit protection circuit recovers the normal power supply of the load after the load short circuit is eliminated.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.
Claims (10)
1. A short-circuit protection circuit, comprising: the device comprises a switch control module, a voltage stabilizing module and a delay detection judging module;
The switch control module is provided with a first input end and a second input end, the first input end is connected with a power supply, the second input end is connected with the output end of the delay detection judging module, and the output end of the switch control module is connected with a load; the switch control module receives the control signal output by the delay detection and judgment module and connects or disconnects a power supply and a load according to the control signal;
The input end of the voltage stabilizing module is connected with the power supply, and the output end of the voltage stabilizing module is connected with the delay detection judging module; the voltage stabilizing module provides reference voltage for the delay detection judging module;
the delay detection judging module is connected between the switch control module and the load; the control circuit is used for detecting the load voltage, comparing the load voltage with the reference voltage to generate a control signal, and transmitting the control signal to the switch control module after delaying preset time.
2. The short-circuit protection circuit of claim 1, wherein the delay detection and determination module comprises: the short circuit detection device comprises a short circuit judgment module and a detection module;
The input end of the detection module is connected between the switch control module and the load, and the output end of the detection module is connected with the short circuit judgment module; the detection module detects load voltage, delays the load voltage for a first preset time and then transmits the load voltage to the short circuit judgment module;
The first input end of the short circuit judging module is connected with the voltage stabilizing module, the second input end of the short circuit judging module is connected with the detecting module, and the output end of the short circuit judging module is connected with the switch control module; the short circuit judging module receives the reference voltage transmitted by the voltage stabilizing module and the load voltage transmitted by the detecting module, compares the load voltage with the reference voltage to generate a control signal, and transmits the control signal to the switch control module after delaying for a second preset time.
3. the short-circuit protection circuit of claim 2,
At least one of the first preset time and the second preset time is greater than zero.
4. the short-circuit protection circuit of claim 3,
the switch control module includes: the MOS transistor comprises a first resistor, a second resistor, a first capacitor and a first MOS transistor;
The source level of the first MOS tube is connected with a power supply, the drain electrode of the first MOS tube is connected with the load, the grid electrode of the first MOS tube is connected with the output end of the short-circuit judging module through the second resistor, and the first resistor and the first capacitor are connected in parallel between the source level of the first MOS tube and the grid electrode of the first MOS tube.
5. the short-circuit protection circuit of claim 4,
The short circuit judgment module comprises: the circuit comprises a first operational amplifier, a third resistor, a fourth resistor and a fifth resistor;
The output end of the first operational amplifier is connected with the second resistor, the inverting input end of the first operational amplifier is connected with the output end of the detection module, and the connecting point of the inverting input end of the first operational amplifier and the detection module is grounded through a third resistor; the non-inverting input end of the first operational amplifier is connected with the voltage stabilizing module through a fifth resistor, and the connection point of the non-inverting input end of the first operational amplifier and the fifth resistor is grounded through a fourth resistor.
6. The short-circuit protection circuit of claim 5,
The detection module comprises: a sixth resistor, a seventh resistor and a second capacitor;
One end of the seventh resistor is connected between the switch control module and the load, and the other end of the seventh resistor is connected with the inverting input end of the first operational amplifier; one end of the sixth resistor is connected with the voltage stabilizing module, and the other end of the sixth resistor is connected with the inverting input end of the first operational amplifier; and a second capacitor is connected in parallel at two ends of the sixth resistor.
7. The short-circuit protection circuit of claim 3,
the switch control module includes: the eighth resistor, the ninth resistor, the third capacitor and the second MOS tube;
the source of the second MOS tube is connected with a power supply, the drain of the second MOS tube is connected with the load, and the grid of the second MOS tube is connected with the output end of the short-circuit judging module through the ninth resistor; one end of the eighth resistor is connected with the voltage stabilizing module, and the other end of the eighth resistor is connected with a connection point of the grid of the second MOS tube and the ninth resistor; one end of the third capacitor is connected with a connection point of the grid electrode of the second MOS tube and the ninth resistor, and the other end of the third capacitor is grounded.
8. the short-circuit protection circuit of claim 7,
The short circuit judgment module comprises: a second operational amplifier, a tenth resistor, an eleventh resistor, and a twelfth resistor;
The output end of the second operational amplifier is connected with the ninth resistor, the non-inverting input end of the second operational amplifier is connected with the output end of the detection module, and the connecting point of the non-inverting input end of the second operational amplifier and the detection module is grounded through a tenth resistor; the reverse input end of the second operational amplifier is connected with the voltage stabilizing module through a twelfth resistor, and the connection point of the reverse input end of the second operational amplifier and the twelfth resistor is grounded through an eleventh resistor.
9. The short-circuit protection circuit of claim 8,
The detection module comprises: a thirteenth resistor, a fourteenth resistor, and a fourth capacitor;
One end of the fourteenth resistor is connected between the switch control module and the load, and the other end of the fourteenth resistor is connected with the non-inverting input end of the second operational amplifier; one end of the thirteenth resistor is connected with the voltage stabilizing module, and the other end of the thirteenth resistor is connected with the non-inverting input end of the second operational amplifier; and a fourth capacitor is connected in parallel with two ends of the thirteenth resistor.
10. The short-circuit protection circuit of claim 8,
The voltage stabilizing module comprises a voltage conversion chip.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920351986.5U CN209805407U (en) | 2019-03-19 | 2019-03-19 | Short-circuit protection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920351986.5U CN209805407U (en) | 2019-03-19 | 2019-03-19 | Short-circuit protection circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209805407U true CN209805407U (en) | 2019-12-17 |
Family
ID=68825498
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920351986.5U Active CN209805407U (en) | 2019-03-19 | 2019-03-19 | Short-circuit protection circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN209805407U (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111413644A (en) * | 2020-04-27 | 2020-07-14 | 力高(山东)新能源技术有限公司 | Short circuit recovery detection method of energy storage battery management system |
| CN112379253A (en) * | 2020-11-06 | 2021-02-19 | 欣旺达电动汽车电池有限公司 | 48V start-stop circuit breaker circuit and state detection method thereof |
| CN112701654A (en) * | 2020-12-04 | 2021-04-23 | 珠海格力电器股份有限公司 | Short-circuit protection device, circuit system and short-circuit protection method thereof |
| CN112928736A (en) * | 2021-02-02 | 2021-06-08 | 苏州赛芯电子科技股份有限公司 | Delay adjustable circuit and lithium battery protection circuit thereof |
| CN113013842A (en) * | 2019-12-19 | 2021-06-22 | 上银科技股份有限公司 | Fan protection device |
| CN113328414A (en) * | 2021-08-02 | 2021-08-31 | 上海芯龙半导体技术股份有限公司南京分公司 | Short-circuit protection circuit |
| CN113331493A (en) * | 2021-05-08 | 2021-09-03 | 铂德（深圳）科技有限公司 | Short-circuit protection circuit and electron cigarette |
| CN115347526A (en) * | 2022-10-17 | 2022-11-15 | 荣耀终端有限公司 | Side fingerprint protection circuit, control method and electronic equipment |
| CN117175487A (en) * | 2023-11-02 | 2023-12-05 | 江苏慕林智造科技股份有限公司 | Short-circuit protection circuit, method and readable storage medium |
-
2019
- 2019-03-19 CN CN201920351986.5U patent/CN209805407U/en active Active
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113013842A (en) * | 2019-12-19 | 2021-06-22 | 上银科技股份有限公司 | Fan protection device |
| CN113013842B (en) * | 2019-12-19 | 2024-05-03 | 上银科技股份有限公司 | Fan protector |
| CN111413644A (en) * | 2020-04-27 | 2020-07-14 | 力高(山东)新能源技术有限公司 | Short circuit recovery detection method of energy storage battery management system |
| CN112379253A (en) * | 2020-11-06 | 2021-02-19 | 欣旺达电动汽车电池有限公司 | 48V start-stop circuit breaker circuit and state detection method thereof |
| CN112701654B (en) * | 2020-12-04 | 2023-02-28 | 珠海格力电器股份有限公司 | Short-circuit protection device, circuit system and short-circuit protection method thereof |
| CN112701654A (en) * | 2020-12-04 | 2021-04-23 | 珠海格力电器股份有限公司 | Short-circuit protection device, circuit system and short-circuit protection method thereof |
| CN112928736A (en) * | 2021-02-02 | 2021-06-08 | 苏州赛芯电子科技股份有限公司 | Delay adjustable circuit and lithium battery protection circuit thereof |
| CN112928736B (en) * | 2021-02-02 | 2022-06-28 | 苏州赛芯电子科技股份有限公司 | Delay adjustable circuit and lithium battery protection circuit thereof |
| CN113331493A (en) * | 2021-05-08 | 2021-09-03 | 铂德（深圳）科技有限公司 | Short-circuit protection circuit and electron cigarette |
| CN113328414A (en) * | 2021-08-02 | 2021-08-31 | 上海芯龙半导体技术股份有限公司南京分公司 | Short-circuit protection circuit |
| CN115347526A (en) * | 2022-10-17 | 2022-11-15 | 荣耀终端有限公司 | Side fingerprint protection circuit, control method and electronic equipment |
| CN117175487A (en) * | 2023-11-02 | 2023-12-05 | 江苏慕林智造科技股份有限公司 | Short-circuit protection circuit, method and readable storage medium |
| CN117175487B (en) * | 2023-11-02 | 2024-02-06 | 江苏慕林智造科技股份有限公司 | Short-circuit protection circuit, method and readable storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN209805407U (en) | Short-circuit protection circuit | |
| CN107894567B (en) | Battery pack and detection system and detection method for interface state of battery pack | |
| US9673643B2 (en) | Battery presence detecting method, apparatus and charging system | |
| CN111316528B (en) | Power supply circuit of terminal equipment, terminal equipment and power supply method | |
| CN101174770B (en) | Charging protection device | |
| CN106965761A (en) | A kind of mobile unit system cut-off protection device | |
| CN101373893A (en) | Over temperature protection circuit for battery | |
| US20200412138A1 (en) | Secondary battery protection apparatus | |
| US10355506B2 (en) | Power supplying system and method | |
| US7884578B2 (en) | Battery charging circuit with backflow prevention transistor, portable electronic device and semiconductor integrated circuit with backflow prevention transistor | |
| US10263440B2 (en) | Short-circuit determination method and electronic device | |
| CN213367449U (en) | Ignition prevention circuit of battery management system and battery pack | |
| US10069312B2 (en) | Charging discharging apparatus for super capacitor modules | |
| CN114928147B (en) | Battery charging protection circuit, chip and power module | |
| US10003213B2 (en) | Power adapter | |
| CN113109738B (en) | Power-down time detection circuit and power-down time detection system | |
| CN210123900U (en) | Output voltage regulating circuit of charger | |
| EP3716011B1 (en) | Power management integrated circuit | |
| CN109659907B (en) | Lithium battery short circuit detection protection method | |
| CN110824377A (en) | Detection circuit of switching power supply | |
| CN206422511U (en) | A kind of Universal Switching Power Supply short-circuit protection circuit | |
| CN218995494U (en) | Port voltage detection circuit and battery control circuit | |
| AU2019202248A1 (en) | Power management integrated circuit | |
| CN216751224U (en) | Standby energy storage power supply circuit and vehicle-mounted equipment | |
| CN115967265B (en) | Anti-overcharging soft start circuit and method, voltage reduction circuit comprising same and switching power supply |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |