Power supply control circuit and circuit breaker

Abstract

The utility model provides a kind of power supply control circuit and circuit breaker, including overvoltage protection trigger module and first switch unit;The output of overvoltage protection trigger module is electrically connected with the controlled end of first switch unit, and the input of overvoltage protection trigger module and the input of first switch unit are respectively used to access initial voltage, and the output of first switch unit is used to output target voltage;Overvoltage protection trigger module is used to control first switch unit to disconnect when initial voltage is greater than first voltage threshold and control first switch unit to conduct when initial voltage drops below second voltage threshold;First voltage threshold is greater than second voltage threshold. Overvoltage protection trigger module uses larger first voltage threshold as overvoltage protection threshold and smaller second voltage threshold as overvoltage recovery threshold, provides a voltage interval from overvoltage protection to overvoltage recovery, can effectively avoid the problem of repeated switching caused by voltage slight fluctuation of power supply system, and improves the stability of power supply.

Description

Technical Field

[0001] This utility model relates to the field of electrical protection technology, specifically to a power supply control circuit and circuit breaker. Background Technology

[0002] In electrical systems, the primary objective of overvoltage protection on the input side is to take measures to prevent damage to the power supply system and downstream electrical systems when the voltage exceeds a safe threshold.

[0003] The specific methods for implementing overvoltage protection typically include using high-precision sensors for real-time monitoring, setting reasonable safety thresholds, quickly cutting off power supply when the voltage exceeds the safety threshold, and restoring power supply when the voltage drops below the safety threshold.

[0004] Existing solutions rely solely on a single safety threshold for overvoltage protection, which causes the power supply system to repeatedly switch on and off when there are slight voltage fluctuations, ultimately reducing the stability of the power supply. Utility Model Content

[0005] In view of the shortcomings of the existing technology, this utility model provides a power supply control circuit and circuit breaker.

[0006] In one embodiment, the present invention provides a power supply control circuit, which includes an overvoltage protection trigger module and a first switching unit.

[0007] The output terminal of the overvoltage protection trigger module is electrically connected to the controlled terminal of the first switching unit. The input terminal of the overvoltage protection trigger module and the input terminal of the first switching unit are respectively used to connect the initial voltage, and the output terminal of the first switching unit is used to output the target voltage.

[0008] The overvoltage protection trigger module is used to control the first switching unit to open when the initial voltage is greater than the first voltage threshold, and to control the first switching unit to open when the initial voltage drops below the second voltage threshold;

[0009] The first voltage threshold is greater than the second voltage threshold.

[0010] In one embodiment, the overvoltage protection triggering module includes a hysteresis comparison unit;

[0011] The first input terminal of the hysteresis comparator is used to connect the initial voltage, the second input terminal of the hysteresis comparator is used to connect the reference voltage, and the output terminal of the hysteresis comparator is electrically connected to the controlled terminal of the first switching unit.

[0012] In one embodiment, the hysteresis comparator includes a comparator, a first resistor, a second resistor, and a third resistor;

[0013] The non-inverting input of the comparator is electrically connected to the second terminal of the first resistor and the first terminal of the second resistor, respectively. The first terminal of the first resistor is used to connect to the initial voltage, and the second terminal of the second resistor is used to ground. The inverting input of the comparator is used to connect to the reference voltage and is electrically connected to the output of the comparator and the controlled terminal of the first switching unit through the third resistor, respectively.

[0014] In one embodiment, the first switching unit includes a first PMOS transistor, and the overvoltage protection trigger module further includes a first NPN transistor and a first PNP transistor;

[0015] The base of the first NPN transistor is electrically connected to the output of the hysteresis comparator. The collector of the first NPN transistor is electrically connected to the base of the first PNP transistor. The emitter of the first PNP transistor is electrically connected to the source of the first PMOS transistor and used to apply the initial voltage. The collector of the first PNP transistor is electrically connected to the gate of the first PMOS transistor and the emitter of the first NPN transistor and used to ground.

[0016] In one embodiment, the first switching unit includes a first PMOS transistor, and the overvoltage protection trigger module includes a first Zener diode, a second Zener diode, a second NPN transistor, a second PNP transistor, and a fourth resistor;

[0017] The cathode of the first Zener diode is electrically connected to the collector of the second NPN transistor and the base of the second PNP transistor, and is used to apply the initial voltage through the fourth resistor. The emitter of the second PNP transistor is electrically connected to the source of the first PMOS transistor and is used to apply the initial voltage. The collector of the second PNP transistor is electrically connected to the gate of the first PMOS transistor, the cathode of the second Zener diode, and the emitter of the second NPN transistor, and is used to ground. The base of the second NPN transistor is electrically connected to the anode of the second Zener diode.

[0018] The voltage regulation voltage of the first Zener diode is the first voltage threshold, and the voltage regulation voltage of the second Zener diode is the second voltage threshold.

[0019] In one embodiment, the power supply control circuit further includes an overload protection trigger module and a second switching unit;

[0020] The output terminal of the overload protection trigger module is electrically connected to the controlled terminal of the second switching unit, the input terminal of the second switching unit is electrically connected to the output terminal of the first switching unit, the output terminal of the second switching unit is used to output load voltage to the load, and the input terminal of the overload protection trigger module is electrically connected to the load circuit where the load is located.

[0021] The overload protection trigger module is used to control the second switching unit to disconnect when an overload occurs.

[0022] In one embodiment, the overload protection trigger module includes a sampling resistor and a first comparison unit;

[0023] The sampling resistor is connected in series in the circuit where the load is located and is electrically connected to the first input terminal of the first comparison unit. The second input terminal of the first comparison unit is used to connect to the reference voltage. The output terminal of the first comparison unit is electrically connected to the controlled terminal of the second switching unit.

[0024] In one embodiment, the overload protection triggering module further includes a sampling amplification unit;

[0025] The sampling resistor is electrically connected to the first input terminal of the first comparison unit through the sampling amplification unit.

[0026] In one embodiment, the sampling amplification unit includes a first operational amplifier, a third NPN transistor, a fifth resistor, a sixth resistor, and a seventh resistor;

[0027] The non-inverting input of the first operational amplifier is electrically connected to the sampling resistor. The inverting input of the first operational amplifier is electrically connected to the second terminal of the sixth resistor and the first terminal of the seventh resistor through the fifth resistor. The output of the first operational amplifier is electrically connected to the base of the third NPN transistor. The collector of the third NPN transistor is electrically connected to the input of the second switching unit. The emitter of the third NPN transistor is electrically connected to the first input of the first comparator unit and the first terminal of the sixth resistor. The second terminal of the seventh resistor is used for grounding.

[0028] In one embodiment, the power supply control circuit further includes a short-circuit protection trigger module;

[0029] The output terminal of the short-circuit protection trigger module is electrically connected to the controlled terminal of the second switching unit, and the input terminal of the short-circuit protection trigger module is electrically connected to the output terminal of the second switching unit.

[0030] The short-circuit protection trigger module is used to control the second switching unit to disconnect when a short circuit occurs in the load.

[0031] In one embodiment, the short-circuit protection triggering module includes a second comparison unit;

[0032] The first input terminal of the second comparison unit is electrically connected to the output terminal of the second switching unit. The second input terminal of the second comparison unit is used to connect to the reference voltage. The output terminal of the second comparison unit is electrically connected to the controlled terminal of the second switching unit.

[0033] In one embodiment, the second switching unit includes a second PMOS transistor, the first comparator unit includes a second operational amplifier and a first diode, the second comparator unit includes a third operational amplifier and a second diode, and the power supply control circuit further includes a timer chip.

[0034] The inverting input of the second operational amplifier is electrically connected to the sampling amplification unit. The non-inverting input of the second operational amplifier and the inverting input of the third operational amplifier are respectively used to connect to the reference voltage. The non-inverting input of the third operational amplifier is electrically connected to the drain of the second PMOS transistor.

[0035] The output terminal of the second operational amplifier is electrically connected to the cathode of the first diode, the output terminal of the third operational amplifier is electrically connected to the cathode of the second diode, the anodes of the first and second diodes are electrically connected to the trigger terminals of the timer chip, and the output terminal of the timer chip is electrically connected to the gate of the second PMOS transistor.

[0036] Secondly, in one embodiment, the present invention provides a circuit breaker, which includes the power supply control circuit in any of the above embodiments.

[0037] Through the aforementioned power supply control circuit and circuit breaker, an overvoltage protection trigger module with an added overvoltage recovery threshold is set up. This allows the overvoltage protection trigger module to control the first switching unit to open when the initial voltage is greater than the first voltage threshold and to control the first switching unit to open when the initial voltage is less than the second voltage threshold. In this process, the overvoltage protection trigger module uses the larger first voltage threshold as the overvoltage protection threshold and the smaller second voltage threshold as the overvoltage recovery threshold, providing a voltage range from overvoltage protection to overvoltage recovery. This effectively avoids the problem of repeated switching caused by slight voltage fluctuations in the power supply system, ultimately improving the stability of the power supply. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of the power supply control circuit in one embodiment of the present invention;

[0040] Figure 2 This is a detailed circuit diagram of an overvoltage protection trigger module using a comparison method in one embodiment of the present invention;

[0041] Figure 3 This is a detailed circuit diagram of a reference module using a reference source method in one embodiment of the present invention;

[0042] Figure 4 This is a detailed circuit diagram of a reference module using a reference chip in one embodiment of the present invention;

[0043] Figure 5This is a detailed circuit diagram of an overvoltage protection trigger module using a voltage regulation method in one embodiment of the present invention;

[0044] Figure 6 This is a schematic diagram of an embodiment of the present invention, including an overload protection trigger module and a short circuit protection trigger module;

[0045] Figure 7 This is a detailed circuit diagram of the overload protection trigger module, the short circuit protection trigger module, and the output module in one embodiment of the present invention. Detailed Implementation

[0046] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0047] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified. In this application, the term "exemplary" is used to mean "used as an example, illustration, or description." Any embodiment described as "exemplary" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to implement and use this invention. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that this invention can be implemented without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the description of this invention with unnecessary detail. Therefore, this invention is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.

[0048] Firstly, such as Figure 1 As shown, in one embodiment, the present invention provides a power supply control circuit, which includes an overvoltage protection trigger module and a first switching unit.

[0049] The first switching unit includes, but is not limited to, mechanical switches, semiconductor switches, etc.

[0050] The output terminal of the overvoltage protection trigger module is electrically connected to the controlled terminal of the first switching unit. The input terminal of the overvoltage protection trigger module and the input terminal of the first switching unit are respectively used to connect the initial voltage Vin, and the output terminal of the first switching unit is used to output the target voltage VCC.

[0051] The first switching unit is used to connect the initial voltage Vin and output the target voltage VCC. It can be understood that when the first switching unit is turned on, it can output the target voltage VCC according to the connected initial voltage Vin, which can be understood as a normal power supply condition. Conversely, when the first switching unit is turned off, it cannot output the target voltage VCC according to the connected initial voltage Vin, which can be understood as a power supply interruption condition.

[0052] The overvoltage protection trigger module can perform threshold judgment on the initial voltage Vin to determine whether there is an overvoltage problem. Based on the detection result, it sends a corresponding control signal to the first switching unit to control the first switching unit to perform the corresponding switching operation.

[0053] The overvoltage protection trigger module is used to control the first switching unit to disconnect when the initial voltage Vin is greater than the first voltage threshold, and to control the first switching unit to turn on when the initial voltage Vin drops below the second voltage threshold; the first voltage threshold is greater than the second voltage threshold.

[0054] It is understandable that the first voltage threshold is greater than the second voltage threshold.

[0055] Specifically, after power-on, the first switching unit is turned on, entering normal power supply mode. When the overvoltage protection trigger module detects that the initial voltage Vin is greater than the first voltage threshold, it determines that the current initial voltage Vin is overvoltage and sends a control signal indicating disconnection to the first switching unit, thereby controlling the first switching unit to disconnect and enter power interruption mode. Subsequently, when the overvoltage protection trigger module detects that the initial voltage Vin has dropped below the second voltage threshold, it determines that the current initial voltage Vin has recovered from overvoltage and sends a control signal indicating turn-on to the first switching unit, thereby controlling the first switching unit to turn on and re-enter normal power supply mode.

[0056] The power supply control circuit described above incorporates an overvoltage protection trigger module with an added overvoltage recovery threshold. This allows the overvoltage protection trigger module to control the first switching unit to disconnect when the initial voltage is greater than the first voltage threshold and to control the first switching unit to conduct when the initial voltage is less than the second voltage threshold. During this process, the overvoltage protection trigger module uses the larger first voltage threshold as the overvoltage protection threshold and the smaller second voltage threshold as the overvoltage recovery threshold, providing a voltage range from overvoltage protection to overvoltage recovery. This effectively avoids repeated switching problems caused by slight voltage fluctuations in the power supply system, ultimately improving the stability of the power supply.

[0057] like Figure 2 As shown, in one embodiment, the first switching unit includes a first PMOS transistor Q1, and the overvoltage protection trigger module includes a hysteresis comparator unit mainly composed of comparator U5, resistor R81, resistor R30 and resistor R29, a first NPN transistor Q51 and a first PNP transistor Q31.

[0058] The non-inverting input of comparator U5 is electrically connected to the second terminal of resistor R81 and the first terminal of resistor R30, respectively. The first terminal of resistor R81 is used to connect the initial voltage Vin, and the second terminal of resistor R30 is used to ground. The inverting input of comparator U5 is used to connect the reference voltage Vref and is electrically connected to the base of the first NPN transistor Q51 through resistors R29, R27, and R28. The collector of the first NPN transistor Q51 is connected to the base of the first PNP transistor Q31 through resistor R10. Electrically connected, the emitter of the first PNP transistor Q31 is electrically connected to the source of the first PMOS transistor Q1 and used to connect to the initial voltage Vin. The base of the first PNP transistor Q31 is also connected to the initial voltage Vin through resistor R7. The collector of the first PNP transistor Q31 is electrically connected to the gate of the first PMOS transistor Q1 and is electrically connected to the emitter of the first NPN transistor Q51 through resistor R12 and used to ground. A resistor R1 is also connected in parallel between the source and gate of the first PMOS transistor Q1.

[0059] When the initial voltage Vin is normal (i.e., not greater than the first voltage threshold), the voltage V+ at the non-inverting input of comparator U5 is Vin*(R30 / (R81+R30)), and the voltage V- at the inverting input of comparator U5 is the reference voltage Vref. At this time, the voltage V+ is less than the voltage V-, the output of comparator U5 is low, the first NPN transistor Q51 is cut off, and the first PNP transistor Q31 is also cut off. After the initial voltage Vin is divided by resistors R1 and R12, the corresponding gate voltage V = Vin*R12 / (R1+R12) is generated at the gate of the first PMOS transistor Q1, which turns on the first PMOS transistor Q1. The output target voltage VCC is the initial voltage Vin, and the load of the subsequent stage begins to work normally. As the initial voltage Vin increases, the voltage V+ also increases until the initial voltage Vin is greater than the first voltage threshold. At this point, the voltage V+ is greater than the voltage V-, the comparator U5 outputs a high level, and the capacitor C5 begins to charge. When the voltage across the capacitor C5 reaches 0.7V, the first NPN transistor Q51 turns on, the base voltage of the first PNP transistor Q31 is pulled down to 0V, and the first PNP transistor Q31 enters the saturation conduction state, while the source and gate of the first PMOS transistor Q1 are saturated and cut off due to a short circuit.

[0060] Furthermore, when the output of comparator U5 goes high because the voltage V+ exceeds the reference voltage Vref, the first PMOS transistor Q1 is turned off. According to the superposition law, V+ = Vin*(R29||R30 / (R29||R30+R81))+0.7*(R81||R30 / (R81||R30+R29)), as the initial voltage Vin decreases, the voltage V+ at the non-inverting input of comparator U5 also decreases. When the initial voltage Vin decreases to a certain level (i.e., less than the second voltage threshold), the output of comparator U5 goes low, and the first NPN transistor Q51 and the first PNP transistor Q31 are turned off. The initial voltage Vin is divided by resistors R1 and R12, and a corresponding gate voltage V = Vin*R12 / (R1+R12) is generated at the gate of the first PMOS transistor Q1, which turns on the first PMOS transistor Q1, and the subsequent circuit resumes normal power supply.

[0061] Among them, Figure 2 In addition, the power supply control circuit also includes capacitors C1 and C2 for output filtering to obtain a more stable target voltage VCC.

[0062] Among them, Figure 2 In addition, the power supply control circuit also includes a clamping diode D1 for input clamping to prevent surges and lightning strikes.

[0063] In other embodiments, other specific types of first switching units and hysteresis comparator units may be used so that the hysteresis comparator unit can directly drive the first switching unit without the first NPN transistor Q51 and the first PNP transistor Q31.

[0064] like Figure 3 As shown, in one embodiment, the power supply control circuit further includes a reference module for generating a reference voltage Vref, the reference module including a resistor R3, a reference source U2, a capacitor C3, and a capacitor C4.

[0065] Resistor R3 is used for current limiting, ensuring that the current flowing through reference source U2 enables reference source U2 to generate a reference voltage Vref. Capacitors C3 and C4 are used for filtering on the output side.

[0066] Specifically, in Figure 3 In this module, the reference module can generate a +2.5V reference voltage Vref based on the input +5V voltage.

[0067] like Figure 4 As shown, in one embodiment, the power supply control circuit further includes a reference module for generating a reference voltage Vref, the reference module including a resistor R3, a reference chip U6, capacitors C12, C13, C3, and C4.

[0068] Similarly, capacitors C12 and C13 are used for filtering on the input side, and capacitors C3 and C4 are used for filtering on the output side.

[0069] Specifically, in Figure 4 In this module, the reference module can generate a +2.5V reference voltage Vref based on the input +5V voltage.

[0070] like Figure 5 As shown, in one embodiment, the first switching unit includes a first PMOS transistor Q1, and the overvoltage protection trigger module includes a first Zener diode VD1, a second Zener diode VD2, a second NPN transistor Q52, a second PNP transistor Q32, and a resistor R82.

[0071] The cathode of the first Zener diode VD1 is electrically connected to the collector of the second NPN transistor Q52, and is electrically connected to the base of the second PNP transistor Q32 through resistor R10, and is used to apply the initial voltage Vin through resistor R82. The emitter of the second PNP transistor Q32 is electrically connected to the source of the first PMOS transistor Q1, and is used to apply the initial voltage Vin. The collector of the second PNP transistor Q32 is electrically connected to the gate of the first PMOS transistor Q1, electrically connected to the cathode of the second Zener diode VD2 through resistor R7, and electrically connected to the emitter of the second NPN transistor Q52 through resistor R12, and is used to ground. The base of the second NPN transistor Q52 is electrically connected to the anode of the second Zener diode VD2 and is grounded through capacitor C5. A resistor R1 is also connected in parallel between the source and gate of the first PMOS transistor Q1.

[0072] The voltage regulation voltage of the first Zener diode VD1 is the first voltage threshold, and the voltage regulation voltage of the second Zener diode VD2 is the second voltage threshold.

[0073] When the initial voltage Vin is normal (i.e., not greater than the first voltage threshold), the first Zener diode VD1 is turned off, and the second PNP transistor Q32 is turned off. After the initial voltage Vin is divided by resistors R1 and R12, the corresponding gate voltage V = Vin * R12 / (R1 + R12) is generated at the gate of the first PMOS transistor Q1, which turns on the first PMOS transistor Q1. The target voltage VCC is the initial voltage Vin, and the load of the subsequent stage begins to work normally. When the initial voltage Vin reaches the regulated voltage of the first Zener diode VD1, the first Zener diode VD1 conducts, and the second PNP transistor Q32 conducts. The first PMOS transistor Q1 is cut off due to the short circuit between its source and gate, and the subsequent circuit cannot be powered and stops working. At the same time, because resistor R1 is short-circuited, the voltage across resistor R12 increases, causing the second Zener diode VD2 to start conducting, and capacitor C5 to start charging. When the voltage across capacitor C5 reaches 0.7V, the second NPN transistor Q52 conducts, and the base voltage of the second PNP transistor Q32 is pulled down to 0V. The second PNP transistor Q32 enters the saturation conduction state, while the first PMOS transistor Q1 remains saturated and cut off.

[0074] Furthermore, when the initial voltage Vin begins to decrease and is greater than the voltage regulation of the second Zener diode VD2 but less than the voltage regulation of the first Zener diode VD1, the first Zener diode VD1 is turned off. However, at this time, the second NPN transistor Q52, the second PNP transistor Q32, and the second Zener diode VD2 are interlocked, so that the second NPN transistor Q52, the second PNP transistor Q32, and the second Zener diode VD2 remain in the conducting state, the first PMOS transistor Q1 continues to remain in the cut-off state, and the subsequent circuit remains inactive. When the initial voltage Vin is less than the regulated voltage of the second Zener diode VD2 (i.e., less than the second voltage threshold), the second Zener diode VD2 is turned off, and capacitor C5 begins to discharge. When the voltage of capacitor C5 drops below 0.7V, the second NPN transistor Q52 is turned off, and at the same time, the second PNP transistor Q32 is also turned off. After the initial voltage Vin is divided by resistors R1 and R12, a corresponding gate voltage V = Vin * R12 / (R1 + R12) is generated at the gate of the first PMOS transistor Q1, which turns on the first PMOS transistor Q1, and the subsequent circuit resumes normal power supply.

[0075] like Figure 6 As shown, in one embodiment, the power supply control circuit further includes an overload protection trigger module and a second switching unit.

[0076] Similar to the first switching unit, the second switching unit includes, but is not limited to, mechanical switches, semiconductor switches, etc.

[0077] The output terminal of the overload protection trigger module is electrically connected to the controlled terminal of the second switching unit, the input terminal of the second switching unit is electrically connected to the output terminal of the first switching unit, the output terminal of the second switching unit is used to output the load voltage Vout to the load, and the input terminal of the overload protection trigger module is electrically connected to the load circuit where the load is located.

[0078] The second switching unit is used to connect to the target voltage VCC and output the load voltage Vout. It can be understood that when the second switching unit is turned on, it can output the load voltage Vout according to the connected target voltage VCC. This condition can be understood as a normal power supply condition. Conversely, when the second switching unit is turned off, it cannot output the load voltage Vout according to the connected target voltage VCC. This condition can be understood as a power supply interruption condition.

[0079] The overload protection trigger module can perform threshold judgment on the current of the load circuit to determine whether there is an overload problem in the load circuit. Based on the detection result, it sends a corresponding control signal to the second switching unit to control the second switching unit to perform the corresponding switching operation.

[0080] The overload protection trigger module is used to control the second switching unit to disconnect when an overload occurs.

[0081] Specifically, after power-on, the second switching unit is turned on, entering normal power supply mode. When the overload protection trigger module detects an overload in the load circuit, it sends a control signal indicating disconnection to the second switching unit, thereby controlling the second switching unit to disconnect and enter power interruption mode. Subsequently, when the overload protection trigger module detects that the overload has been eliminated, it sends a control signal indicating turn-on to the second switching unit, thereby controlling the second switching unit to turn on and re-enter normal power supply mode.

[0082] like Figure 6 As shown, in one embodiment, the power supply control circuit further includes a short-circuit protection trigger module.

[0083] The output terminal of the short-circuit protection trigger module is electrically connected to the controlled terminal of the second switching unit, and the input terminal of the short-circuit protection trigger module is electrically connected to the output terminal of the second switching unit.

[0084] The short-circuit protection trigger module can perform threshold judgment on the load voltage Vout to determine whether there is a short circuit in the load circuit. Based on the detection result, it sends a corresponding control signal to the second switching unit to control the second switching unit to perform the corresponding switching operation.

[0085] The short-circuit protection trigger module is used to control the second switching unit to disconnect when a short circuit occurs in the load.

[0086] Specifically, after power-on, the second switching unit is turned on, entering normal power supply mode. When the short-circuit protection trigger module detects a short circuit in the load circuit, it sends a control signal indicating disconnection to the second switching unit, thereby controlling the second switching unit to disconnect and enter power interruption mode. Subsequently, when the short-circuit protection trigger module detects that the short circuit has been cleared, it sends a control signal indicating turn-on to the second switching unit, thereby controlling the second switching unit to turn on and re-enter normal power supply mode.

[0087] like Figure 7 As shown, in one embodiment, the overload protection trigger module includes a sampling resistor R23, a sampling discharge unit mainly composed of a first operational amplifier U4, a third NPN transistor Q4, resistors R14, R16, and R17, and a first comparator unit mainly composed of a second operational amplifier U1B and a first diode D4. The short-circuit protection trigger module includes a second comparator unit mainly composed of a third operational amplifier U1A and a second diode D5. The power supply control circuit also includes a timer chip U3. The second switching unit includes a second PMOS transistor Q2.

[0088] The sampling resistor R23 is connected in series in the circuit where the load is located (in Figure 7In this circuit, the sampling resistor R23 is specifically connected in series between the ground GND and the negative load voltage Vout-. The non-inverting input of the first operational amplifier U4 is electrically connected to the sampling resistor R23. The inverting input of the first operational amplifier U4 is electrically connected to the second end of resistor R16 and the first end of resistor R17 through resistor R14. The output of the first operational amplifier U4 is electrically connected to the base of the third NPN transistor Q4. The collector of the third NPN transistor Q4 is electrically connected to the source of the second PMOS transistor Q2. The emitter of the third NPN transistor Q4 is electrically connected to the inverting input of the second operational amplifier U1B and the first end of resistor R16. The second end of resistor R17 is used for grounding.

[0089] The non-inverting input of the second operational amplifier U1B and the inverting input of the third operational amplifier U1A are respectively used to connect to the reference voltage Vref. The non-inverting input of the third operational amplifier U1A is electrically connected to the drain of the second PMOS transistor Q2.

[0090] The output terminal of the second operational amplifier U1B is electrically connected to the cathode of the first diode D4, the output terminal of the third operational amplifier U1A is electrically connected to the cathode of the second diode D5, the anode of the first diode D4 and the anode of the second diode D5 are electrically connected to the trigger terminal TRIG of the timer chip U3, and the output terminal OUT of the timer chip U3 is electrically connected to the gate of the second PMOS transistor Q2.

[0091] Under normal operating conditions, the sampling resistor R23 generates a sampling voltage based on the load current flowing through it. The voltage at the non-inverting input of the second operational amplifier U1B is the reference voltage Vref. The voltage at the inverting input of the second operational amplifier U1B is less than the reference voltage Vref. The output of the second operational amplifier U1B is high, the first diode D4 is cut off, the trigger terminal TRIG of the timer chip U3 is high, the output terminal OUT of the timer chip U3 is low, the second PMOS transistor Q2 is turned on, and the load voltage Vout (including the positive load voltage Vout+ and the negative load voltage Vout-) is output normally.

[0092] When the load increases, the sampling voltage generated by the sampling resistor R23 also increases, causing the voltage V1Ap input to the non-inverting input of the first operational amplifier U4 to also increase. After being amplified by the first operational amplifier U4 and the third NPN transistor Q4, a voltage Vis is generated across resistor R16. After being divided by resistor R17, the voltage is fed back to the inverting input of the first operational amplifier U4 as the voltage V1An. When the voltage Vis exceeds the reference voltage Vref, the second operational amplifier U1B outputs a low level, the first diode D4 conducts, the trigger terminal TRIG of the timer chip U3 outputs a low level, the output terminal OUT of the timer chip U3 outputs a high level, the second PMOS transistor Q2 is cut off, and the load voltage Vout cannot be output, thus achieving protection shutdown. The output overload protection current I = Vref * (R17 / (R17 + R16)) / R23. After the load recovers from overload, the second operational amplifier U1B outputs a high level, the first diode D4 is cut off, the trigger terminal TRIG of the timer chip U3 outputs a high level, the output terminal OUT of the timer chip U3 outputs a low level, the second PMOS transistor Q2 is turned on, the load voltage Vout is output normally, and the load continues to work.

[0093] When the load is short-circuited, the voltage at the non-inverting input of the third operational amplifier U1A is close to 0V. Since the voltage at the inverting input of the third operational amplifier U1A = Vref * (R22 / (R22 + R19)), the third operational amplifier U1A outputs a low level, the second diode D5 conducts, the trigger terminal TRIG of the timer chip U3 outputs a low level, the output terminal OUT of the timer chip U3 outputs a high level, the second PMOS transistor Q2 is cut off, and the Vout output is turned off. After the load recovers from the short circuit, the third operational amplifier U1A outputs a high level, the second diode D5 is cut off, the trigger terminal TRIG of the timer chip U3 outputs a high level, the output terminal OUT of the timer chip U3 outputs a low level, the second PMOS transistor Q2 conducts, and the load voltage Vout is output normally, maintaining the operation of the load.

[0094] Among them, the first diode D4 and the second diode D5 form an AND gate logic circuit, and the time base chip U3 forms a trigger flip circuit.

[0095] like Figure 7 As shown, in one embodiment, the power supply control circuit further includes an output module, which includes a clamping diode D3, a capacitor C6, and a capacitor C7.

[0096] Among them, clamping diode D3, capacitor C6 and capacitor C7 are connected in parallel with load resistor Rload. Clamping diode D3 is used to prevent surges, and capacitors C6 and C7 are used for filtering.

[0097] Secondly, in one embodiment, the present invention provides a circuit breaker, which includes the power supply control circuit in any of the above embodiments.

[0098] The power supply control circuit included in the circuit breaker is equipped with an overvoltage protection trigger module that includes an overvoltage recovery threshold. This allows the overvoltage protection trigger module to control the first switching unit to open when the initial voltage is greater than the first voltage threshold and to control the first switching unit to open when the initial voltage is less than the second voltage threshold. In this process, the overvoltage protection trigger module uses the larger first voltage threshold as the overvoltage protection threshold and the smaller second voltage threshold as the overvoltage recovery threshold, providing a voltage range from overvoltage protection to overvoltage recovery. This effectively avoids repeated switching problems caused by slight voltage fluctuations in the power supply system, ultimately improving the stability of the power supply.

[0099] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the detailed descriptions of other embodiments above, which will not be repeated here.

[0100] The power supply control circuit and circuit breaker provided by this utility model have been described in detail above. Specific examples have been used to illustrate the principle and implementation of this utility model. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​this utility model. Therefore, the content of this specification should not be construed as a limitation of this utility model.

[0101] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A power supply control circuit, characterized in that, The power supply control circuit includes an overvoltage protection trigger module and a first switching unit; The output terminal of the overvoltage protection trigger module is electrically connected to the controlled terminal of the first switching unit. The input terminal of the overvoltage protection trigger module and the input terminal of the first switching unit are respectively used to connect the initial voltage, and the output terminal of the first switching unit is used to output the target voltage. The overvoltage protection trigger module is used to control the first switching unit to disconnect when the initial voltage is greater than the first voltage threshold, and to control the first switching unit to turn on when the initial voltage drops below the second voltage threshold.

2. The power supply control circuit according to claim 1, characterized in that, The overvoltage protection triggering module includes a hysteresis comparison unit; The first input terminal of the hysteresis comparator is used to connect to the initial voltage, the second input terminal of the hysteresis comparator is used to connect to the reference voltage, and the output terminal of the hysteresis comparator is electrically connected to the controlled terminal of the first switching unit.

3. The power supply control circuit according to claim 2, characterized in that, The hysteresis comparison unit includes a comparator, a first resistor, a second resistor, and a third resistor; The non-inverting input terminal of the comparator is electrically connected to the second terminal of the first resistor and the first terminal of the second resistor, respectively. The first terminal of the first resistor is used to connect to the initial voltage, and the second terminal of the second resistor is used to ground. The inverting input terminal of the comparator is used to connect to the reference voltage and is electrically connected to the output terminal of the comparator and the controlled terminal of the first switching unit through the third resistor, respectively.

4. The power supply control circuit according to claim 2, characterized in that, The first switching unit includes a first PMOS transistor, and the overvoltage protection trigger module further includes a first NPN transistor and a first PNP transistor; The base of the first NPN transistor is electrically connected to the output terminal of the hysteresis comparator unit. The collector of the first NPN transistor is electrically connected to the base of the first PNP transistor. The emitter of the first PNP transistor is electrically connected to the source of the first PMOS transistor and is used to connect to the initial voltage. The collector of the first PNP transistor is electrically connected to the gate of the first PMOS transistor and the emitter of the first NPN transistor and is used to ground.

5. The power supply control circuit according to claim 1, characterized in that, The first switching unit includes a first PMOS transistor, and the overvoltage protection trigger module includes a first Zener diode, a second Zener diode, a second NPN transistor, a second PNP transistor, and a fourth resistor; The cathode of the first Zener diode is electrically connected to the collector of the second NPN transistor and the base of the second PNP transistor, respectively, and is used to access the initial voltage through the fourth resistor. The emitter of the second PNP transistor is electrically connected to the source of the first PMOS transistor and is used to access the initial voltage. The collector of the second PNP transistor is electrically connected to the gate of the first PMOS transistor, the cathode of the second Zener diode, and the emitter of the second NPN transistor, respectively, and is used to ground. The base of the second NPN transistor is electrically connected to the anode of the second Zener diode. Wherein, the voltage regulation of the first Zener diode is the first voltage threshold, and the voltage regulation of the second Zener diode is the second voltage threshold.

6. The power supply control circuit according to claim 1, characterized in that, The power supply control circuit also includes an overload protection trigger module and a second switching unit. The output terminal of the overload protection trigger module is electrically connected to the controlled terminal of the second switching unit, the input terminal of the second switching unit is electrically connected to the output terminal of the first switching unit, the output terminal of the second switching unit is used to output load voltage to the load, and the input terminal of the overload protection trigger module is electrically connected to the load circuit where the load is located. The overload protection trigger module is used to control the second switching unit to disconnect when the load is overloaded.

7. The power supply control circuit according to claim 6, characterized in that, The overload protection trigger module includes a sampling resistor and a first comparison unit; The sampling resistor is connected in series in the load circuit where the load is located and is electrically connected to the first input terminal of the first comparison unit. The second input terminal of the first comparison unit is used to connect to the reference voltage, and the output terminal of the first comparison unit is electrically connected to the controlled terminal of the second switching unit.

8. The power supply control circuit according to claim 7, characterized in that, The overload protection triggering module also includes a sampling amplification unit; The sampling resistor is electrically connected to the first input terminal of the first comparison unit through the sampling amplification unit.

9. The power supply control circuit according to claim 8, characterized in that, The sampling amplification unit includes a first operational amplifier, a third NPN transistor, a fifth resistor, a sixth resistor, and a seventh resistor; The non-inverting input of the first operational amplifier is electrically connected to the sampling resistor. The inverting input of the first operational amplifier is electrically connected to the second terminal of the sixth resistor and the first terminal of the seventh resistor through the fifth resistor. The output of the first operational amplifier is electrically connected to the base of the third NPN transistor. The collector of the third NPN transistor is electrically connected to the input of the second switching unit. The emitter of the third NPN transistor is electrically connected to the first input of the first comparator unit and the first terminal of the sixth resistor. The second terminal of the seventh resistor is used for grounding.

10. The power supply control circuit according to claim 8, characterized in that, The power supply control circuit also includes a short-circuit protection trigger module; The output terminal of the short-circuit protection trigger module is electrically connected to the controlled terminal of the second switching unit, and the input terminal of the short-circuit protection trigger module is electrically connected to the output terminal of the second switching unit. The short-circuit protection trigger module is used to control the second switching unit to disconnect when a short circuit occurs in the load.

11. The power supply control circuit according to claim 10, characterized in that, The short-circuit protection triggering module includes a second comparison unit; The first input terminal of the second comparison unit is electrically connected to the output terminal of the second switching unit, the second input terminal of the second comparison unit is used to connect to the reference voltage, and the output terminal of the second comparison unit is electrically connected to the controlled terminal of the second switching unit.

12. The power supply control circuit according to claim 11, characterized in that, The second switching unit includes a second PMOS transistor, the first comparison unit includes a second operational amplifier and a first diode, the second comparison unit includes a third operational amplifier and a second diode, and the power supply control circuit also includes a timer chip; The inverting input terminal of the second operational amplifier is electrically connected to the sampling amplification unit. The non-inverting input terminal of the second operational amplifier and the inverting input terminal of the third operational amplifier are respectively used to connect to the reference voltage. The non-inverting input terminal of the third operational amplifier is electrically connected to the drain of the second PMOS transistor. The output terminal of the second operational amplifier is electrically connected to the cathode of the first diode, the output terminal of the third operational amplifier is electrically connected to the cathode of the second diode, the anodes of the first diode and the second diode are respectively electrically connected to the trigger terminal of the time base chip, and the output terminal of the time base chip is electrically connected to the gate of the second PMOS transistor.

13. A circuit breaker, characterized in that, The circuit breaker includes the power supply control circuit as described in any one of claims 1 to 12.

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