Power supply circuit and circuit breaker

Abstract

The utility model provides a power supply circuit and a circuit breaker. The power supply circuit comprises a power supply voltage output circuit, a detection circuit and a step-down circuit. When it is detected that the first voltage is smaller than the first threshold voltage, the detection circuit transmits an enabling signal used for enabling the power supply voltage output circuit to the power supply voltage output circuit, so that the power supply voltage output circuit is enabled. Thus, under the condition that the first voltage is smaller than the first threshold voltage, after enabling, the power supply voltage output circuit can boost the second voltage to obtain the first power supply voltage, and transmit the first power supply voltage to the step-down circuit, so that the step-down circuit obtains the first power supply voltage. Therefore, the step-down circuit can carry out step-down processing on the first power supply voltage to obtain the second power supply voltage, and transmits the second power supply voltage to the microprocessor, so that the microprocessor can continue to work, and the microprocessor can have enough time to store fault information representing that the circuit breaker breaks down into the memory. And complete storage of fault information can be ensured.

Description

Technical Field

[0001] This application relates to the technical field of circuit breakers, and in particular to a power supply circuit and a circuit breaker. Background Art

[0002] A circuit breaker generally includes a microprocessor and a memory. When a fault such as a power outage occurs in the circuit breaker, the microprocessor needs a certain period of time to store the fault information of the circuit breaker in the memory for the operation and maintenance of the circuit breaker. In the related art, only an electrolytic capacitor is added to extend the power-off time of the microprocessor so that the microprocessor has enough time to store the fault information in the memory. However, since a load such as a motor in the circuit breaker also consumes electric energy, the power-off time of the microprocessor is uncertain. Therefore, the microprocessor does not have enough time to store the fault information in the memory, resulting in incomplete storage of the fault information. Summary of the Utility Model

[0003] This application provides a power supply circuit that can continue to supply power to the microprocessor when a circuit breaker fails, enabling the microprocessor to have enough time to store the fault information in the memory and ensuring complete storage of the fault information.

[0004] In a first aspect, this application provides a power supply circuit. The power supply circuit is applied to a circuit breaker, and the circuit breaker includes a microprocessor. The power supply circuit includes a power supply voltage output circuit, a detection circuit, and a buck circuit.

[0005] The input end of the power supply voltage output circuit and the input end of the detection circuit are both used to access a first voltage. The enable end of the power supply voltage output circuit is electrically connected to the output end of the detection circuit. The output end of the power supply voltage output circuit is electrically connected to the input end of the buck circuit. The output end of the buck circuit is electrically connected to the power supply end of the microprocessor.

[0006] The detection circuit is configured to transmit an enable signal to the power supply voltage output circuit when detecting that the first voltage is less than a first threshold voltage. The enable signal is used to enable the power supply voltage output circuit.

[0007] The power supply voltage output circuit is configured to boost a second voltage to obtain a first power supply voltage and transmit the first power supply voltage to the buck circuit when enabled in the case that the first voltage is less than the first threshold voltage.

[0008] The buck circuit is configured to step down the first power supply voltage to obtain a second power supply voltage and transmit the second power supply voltage to the microprocessor, so that the microprocessor stores the fault information in the memory. The fault information is used to characterize that a fault has occurred in the circuit breaker.

[0009] Through the power supply circuit provided by the first aspect, when it is detected that the first voltage is less than the first threshold voltage, the detection circuit can transmit an enable signal for enabling the power supply voltage output circuit to the power supply voltage output circuit, enabling the power supply voltage output circuit. In this way, in the case where the first voltage is less than the first threshold voltage, after being enabled, the power supply voltage output circuit can boost the second voltage to obtain the first power supply voltage and transmit the first power supply voltage to the buck circuit, so that the buck circuit can obtain the first power supply voltage. Thus, the buck circuit can step down the first power supply voltage to obtain the second power supply voltage and transmit the second power supply voltage to the microprocessor, enabling the microprocessor to continue operating, so that the microprocessor has sufficient time to store the fault information indicating that the circuit breaker has failed in the memory, ensuring the integrity of the stored fault information.

[0010] In a possible design, the power supply circuit further includes: a charging circuit;

[0011] The input end of the charging circuit is electrically connected to the output end of the power supply voltage output circuit, and the output end of the charging circuit is electrically connected to the charging end of the power supply voltage output circuit;

[0012] The power supply voltage output circuit is further configured to transmit a third power supply voltage to the charging circuit in the case where the first voltage is equal to or greater than the first threshold voltage;

[0013] The charging circuit is configured to charge a first capacitor in the power supply voltage output circuit according to the third power supply voltage, so that the power supply voltage output circuit uses the voltage on the first capacitor as the second voltage, and stops charging the first capacitor when the second voltage is greater than a second threshold voltage.

[0014] In a possible design, the power supply voltage output circuit includes: a first capacitor, a boost module, and a first diode;

[0015] The first plate of the first capacitor and the input end of the boost module are both electrically connected to the output end of the charging circuit. The enable end of the boost module is electrically connected to the output end of the detection circuit. The output end of the boost module is electrically connected to the negative electrode of the first diode. The input end of the buck circuit is electrically connected between the output end of the boost module and the negative electrode of the first diode. The positive electrode of the first diode is used to connect to the first voltage;

[0016] The boost module is configured to boost the second voltage to obtain the first power supply voltage after being enabled.

[0017] In a possible design, the boost module includes: a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a second diode, a first inductor, a first resistor, a second resistor, a third resistor, a boost converter chip, and a first feedback component;

[0018] A first end of the first inductor is electrically connected to an output end of the charging circuit, a second end of the first inductor is electrically connected to a positive electrode of the second diode, a negative electrode of the second diode and a first plate of the second capacitor are both electrically connected to a negative electrode of the first diode, a switching pin of the boost converter chip is electrically connected between the second end of the first inductor and the positive electrode of the second diode, an output pin of the boost converter chip and an input end of the first feedback component are both electrically connected between the negative electrode of the second diode and the negative electrode of the first diode, an enable pin of the boost converter chip is electrically connected to an output end of the detection circuit, a feedback pin of the boost converter chip is electrically connected to an output end of the first feedback component, a power pin of the boost converter chip is grounded through the third capacitor, a first pin of the boost converter chip is respectively electrically connected to a first plate of the fourth capacitor and a first end of the first resistor, a second pin of the boost converter chip is respectively electrically connected to a first plate of the fifth capacitor and a first end of the second resistor, a third pin of the boost converter chip is electrically connected to a first end of the third resistor, a second plate of the second capacitor, a second plate of the fourth capacitor, a second plate of the fifth capacitor, a second end of the first resistor, a second end of the second resistor, a second end of the third resistor, and a ground pin of the boost converter chip are all grounded;

[0019] The boost converter chip is configured to boost the second voltage through the first inductor, the second diode, and the second capacitor to obtain the first supply voltage;

[0020] The first feedback component is configured to transmit a first feedback voltage to the boost converter chip according to the first supply voltage to adjust the first supply voltage.

[0021] In a possible design, the detection circuit includes: a first transistor, a fourth resistor, a fifth resistor, and a sixth resistor;

[0022] The first end of the fourth resistor is used to access the first voltage. The second end of the fourth resistor is electrically connected to the first end of the fifth resistor. The gate terminal of the first transistor is electrically connected between the second end of the fourth resistor and the first end of the fifth resistor. The source terminal of the first transistor is used to access the power supply voltage. The drain terminal of the first transistor is electrically connected to the first end of the sixth resistor. The enable terminal of the power supply voltage output circuit is electrically connected between the drain terminal of the first transistor and the first end of the sixth resistor. The second ends of both the fifth resistor and the sixth resistor are grounded.

[0023] In a possible design, the charging circuit includes: a detection module, a control module, a first current-limiting resistor, a second current-limiting resistor, a second transistor, and a first triode.

[0024] The first end of the first current-limiting resistor and the emitter of the first triode are both electrically connected to the output terminal of the power supply voltage output circuit. The second end of the first current-limiting resistor is electrically connected to the drain terminal of the second transistor. The source terminal of the second transistor and the input terminal of the detection module are both electrically connected to the charging terminal of the power supply voltage output circuit. The gate terminal of the second transistor is electrically connected to the first end of the second current-limiting resistor. The output terminal of the detection module is electrically connected to the first end of the control module. The second end of the control module is electrically connected between the second end of the first current-limiting resistor and the drain terminal of the second transistor. The third end of the control module is electrically connected to the base of the first triode. The collector of the first triode and the second end of the second current-limiting resistor are both electrically connected between the source terminal of the second transistor and the input terminal of the detection module.

[0025] The detection module is configured to transmit a detection signal to the control module when it detects that the second voltage is greater than the second threshold voltage.

[0026] The control module is configured to control the first triode to conduct according to the detection signal, so that the charging circuit stops charging the first capacitor.

[0027] In a possible design, the control module includes: a seventh resistor, an eighth resistor, and a controller.

[0028] The first end of the seventh resistor is electrically connected between the second end of the first current-limiting resistor and the drain end of the second transistor. The second end of the seventh resistor is electrically connected to the first end of the eighth resistor. The second end of the eighth resistor is electrically connected to the second end of the controller. The first end of the controller is electrically connected to the output end of the detection module. The base of the first triode is electrically connected between the second end of the seventh resistor and the first end of the eighth resistor. The third end of the controller is grounded.

[0029] In a possible design, the buck circuit includes: a buck converter chip, a filtering component, and a second feedback component;

[0030] The power supply pin of the buck converter chip is electrically connected to the output end of the power supply voltage output circuit. The switching pin of the buck converter chip is electrically connected to the input end of the filtering component. The output end of the filtering component is respectively electrically connected to the input end of the second feedback component and the power supply end of the microprocessor. The output end of the second feedback component is electrically connected to the feedback pin of the buck converter chip;

[0031] The buck converter chip is configured to convert the first power supply voltage into a pulse voltage and transmit the pulse voltage to the filtering component;

[0032] The filtering component is configured to convert the pulse voltage into the second power supply voltage;

[0033] The second feedback component is configured to obtain the second power supply voltage from the filtering component and transmit a second feedback voltage to the buck converter chip according to the second power supply voltage to adjust the second power supply voltage.

[0034] In a possible design, the filtering component includes: a second inductor, a sixth capacitor, a seventh capacitor, and an eighth capacitor;

[0035] The first end of the second inductor is electrically connected to the switching pin of the buck converter chip. The second end of the second inductor is respectively electrically connected to the first plate of the sixth capacitor, the first plate of the seventh capacitor, the first plate of the eighth capacitor, and the input end of the second feedback component.

[0036] In a second aspect, the present application provides a circuit breaker, which includes: a microprocessor, a memory, and the power supply circuit in the first aspect and each possible design of the first aspect;

[0037] The output end of the power supply circuit is respectively electrically connected to the power supply end of the microprocessor and the power supply end of the memory.

[0038] For the circuit breaker provided in the second aspect and each possible design of the second aspect, the beneficial effects can be referred to the beneficial effects brought by the first aspect and each possible implementation manner of the first aspect, which will not be elaborated herein.

[0039] The above description is only an overview of the technical solutions of the embodiments of the present application. In order to understand the technical means of the embodiments of the present application more clearly, it can be implemented according to the content of the description. And in order to make the above and other purposes, features and advantages of the embodiments of the present application more obvious and understandable, the following specifically describes the specific implementation manners of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required to be used in the description of the embodiments. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings.

[0041] Figure 1 FIG.

[0042] Figure 2 FIG.

[0043] Figure 3 FIG.

[0044] Figure 4 FIG.

[0045] Figure 5 is Figure 4 a schematic structural diagram of a controller in the charging circuit;

[0046] Figure 6 FIG.

[0047] DESCRIPTION OF THE REFERENCE NUMERALS

[0048] 100, power supply circuit; 110, power supply voltage output circuit; 120, detection circuit; 130, buck circuit; 140, charging circuit; 200, microprocessor; 300, memory; 400, trip controller. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0049] In this application, "at least one" refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a alone, b alone, or c alone can represent: a alone, b alone, c alone, a and b in combination, a and c in combination, b and c in combination, or a, b, and c in combination, where a, b, and c can be single or multiple. In addition, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance.

[0050] The directions or positional relationships indicated by terms such as "center", "longitudinal", "lateral", "up", "down", "left", "right", "front", and "back" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the present application.

[0051] The terms "connected" and "connect" should be interpreted broadly. For example, "connected" or "connected" in a circuit structure can refer not only to a physical connection, but also to an electrical connection or a signal connection. For example, it can be a direct connection, i.e., a physical connection, or an indirect connection through at least one intermediate component, as long as the circuit is interconnected. It can also refer to internal connectivity between two components. Signal connection can refer not only to signal connection through circuits but also to signal connection through media, such as radio waves. Those skilled in the art will understand the specific meanings of the above terms in this application on a case-by-case basis.

[0052] Reference Figure 1 , Figure 1 This is a schematic diagram of a power supply circuit provided in one embodiment of the present application. Figure 1 As shown, the power supply circuit 100 may include: a power supply voltage output circuit 110 , a detection circuit 120 and a voltage reduction circuit 130 .

[0053] The input end of the power supply voltage output circuit 110 and the input end of the detection circuit 120 are both used to connect to the first voltage V - 12V. The enable end of the power supply voltage output circuit 110 is electrically connected to the output end of the detection circuit 120. The output end of the power supply voltage output circuit 110 is electrically connected to the input end of the buck circuit 130. The output end of the buck circuit 130 is electrically connected to the power supply end of the microprocessor 200.

[0054] Among them, the power supply voltage output circuit 110, the detection circuit 120, and the buck circuit 130 can be set separately or integrated. The embodiments of the present application do not make specific limitations on this.

[0055] Among them, the first voltage V - 12V is, for example, 12V. The first voltage V - 12V can be obtained by converting three-phase alternating current into direct current voltage, or can be obtained by converting single-phase alternating voltage into direct current. The embodiments of the present application do not make specific limitations on this.

[0056] Among them, the buck circuit 130 can be a low dropout linear regulator or a buck converter BUCK.

[0057] When it is detected that the first voltage V - 12V is less than the first threshold voltage, that is, when it is detected that an abnormal power failure occurs in the first voltage V - 12V, the detection circuit 120 can transmit an enable signal to the power supply voltage output circuit 110 to enable the power supply voltage output circuit 110.

[0058] Among them, the enable signal is used to enable the power supply voltage output circuit 110.

[0059] In this way, when the first voltage V - 12V is less than the first threshold voltage, after the power supply voltage output circuit 110 is enabled, the power supply voltage output circuit 110 can boost the second voltage to obtain the first power supply voltage. And the power supply voltage output circuit 110 can transmit the first power supply voltage to the buck circuit 130.

[0060] Among them, the voltage value of the first power supply voltage is almost equal to the voltage value of the first voltage V - 12V before power failure.

[0061] In this way, the buck circuit 130 can step down the first power supply voltage to obtain the second power supply voltage. And the buck circuit 130 can transmit the second power supply voltage to the microprocessor 200, enabling the microprocessor 200 to continue to work, so that the microprocessor 200 can have enough time to store the fault information in the memory even when an abnormal power failure occurs in the first voltage V - 12V. Thus, it can ensure the complete storage of the fault information.

[0062] Among them, the fault information is used to characterize that a fault has occurred in the circuit breaker. Generally, the fault information includes: a voltage fault, a current fault, and the cause of the fault.

[0063] Among them, the second supply voltage is, for example, 3.3V or 5V.

[0064] In addition, when a fault such as a short circuit occurs in the load of the circuit breaker, the buck circuit 130 can transmit the second supply voltage to the trip unit in the circuit breaker to supply power to the trip unit, so that the microprocessor 200 can control the trip unit to trip by controlling the trip controller in the circuit breaker, preventing the scope of the short - circuit fault from expanding.

[0065] For the power supply circuit provided in this application, when it is detected that the first voltage is less than the first threshold voltage, the detection circuit can transmit an enable signal for enabling the power supply voltage output circuit to the power supply voltage output circuit, enabling the power supply voltage output circuit. In this way, when the first voltage is less than the first threshold voltage, after being enabled, the power supply voltage output circuit can boost the second voltage to obtain the first supply voltage and transmit the first supply voltage to the buck circuit, enabling the buck circuit to obtain the first supply voltage. Thus, the buck circuit can step - down the first supply voltage to obtain the second supply voltage and transmit the second supply voltage to the microprocessor, enabling the microprocessor to continue working, so that the microprocessor can have enough time to store the fault information indicating that a fault has occurred in the circuit breaker in the memory, ensuring the integrity of the fault information storage.

[0066] Based on the description of the above - mentioned embodiments, exemplarily, a possible implementation manner of the power supply circuit 100. As Figure 1 shown, the power supply circuit 100 may further include: a charging circuit 140.

[0067] The input end of the charging circuit 140 is electrically connected to the output end of the power supply voltage output circuit 110, and the output end of the charging circuit 140 is electrically connected to the charging end of the power supply voltage output circuit 110.

[0068] When the first voltage V - 12V is equal to or greater than the first threshold voltage, that is, when there is no abnormal power - off of the first voltage V - 12V, the power supply voltage output circuit 110 can transmit the third supply voltage to the charging circuit 140, enabling the charging circuit 140 to obtain the third supply voltage.

[0069] In this way, the charging circuit 140 can charge the first capacitor C1 in the power supply voltage output circuit 110 according to the third supply voltage, enabling the power supply voltage output circuit 110 to use the voltage on the first capacitor C1 as the second voltage, so that when the first voltage V - 12V is powered off, the power supply voltage output circuit 110 can boost the second voltage.

[0070] Moreover, when the second voltage is greater than the second threshold voltage, the power supply voltage output circuit 110 stops charging the first capacitor C1 to avoid overcharging the first capacitor C1.

[0071] Among them, the second threshold voltage is related to the first capacitor C1.

[0072] Based on the description of the above embodiments, exemplarily, a possible implementation manner of the power supply voltage output circuit 110. Refer to Figure 2 , Figure 2 shows Figure 1 the structural schematic diagram of the power supply voltage output circuit in Figure 2 As shown, the power supply voltage output circuit 110 may include: a first capacitor C1, a boost module 111, and a first diode D1.

[0073] The first electrode plate of the first capacitor C1 and the input end of the boost module 111 are both electrically connected to the output end of the charging circuit 140. The enable end of the boost module 111 is electrically connected to the output end of the detection circuit 120. The output end of the boost module 111 is electrically connected to the negative electrode of the first diode D1. The input end of the buck circuit 130 is electrically connected between the output end of the boost module 111 and the negative electrode of the first diode D1. The positive electrode of the first diode D1 is used to connect to the first voltage V - 12V.

[0074] Among them, the capacitance value of the first capacitor C1 is usually 10 μF, that is to say, the first capacitor C1 is a supercapacitor.

[0075] In some examples, the boost module 111 may include: a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, a second diode D2, a first inductor L1, a first resistor R1, a second resistor R2, a third resistor R3, a boost converter chip U1, and a first feedback component 111-1.

[0076] The boost module 111 is used to boost the second voltage to obtain the first supply voltage after being enabled.

[0077] The first end of the first inductor L1 is electrically connected to the output end of the charging circuit 140. The second end of the first inductor L1 is electrically connected to the positive electrode of the second diode D2. The negative electrode of the second diode D2 and the first plate of the second capacitor C2 are both electrically connected to the negative electrode of the first diode D1. The switching pin SW1 of the boost converter chip U1 is electrically connected between the second end of the first inductor L1 and the positive electrode of the second diode D2. The output pin OUT1 of the boost converter chip U1 and the input end of the first feedback component 111-1 are both electrically connected between the negative electrode of the second diode D2 and the negative electrode of the first diode D1. The enable pin EN1 of the boost converter chip U1 is electrically connected to the output end of the detection circuit 120. The feedback pin FB1 of the boost converter chip U1 is electrically connected to the output end of the first feedback component 111-1. The power supply pin VCC1 of the boost converter chip U1 is grounded through the third capacitor C3. The first pin SS / EMI of the boost converter chip U1 is electrically connected to the first plate of the fourth capacitor C4 and the first end of the first resistor R1 respectively. The second pin COMP of the boost converter chip U1 is electrically connected to the first plate of the fifth capacitor C5 and the first end of the second resistor R2 respectively. The third pin ILIM of the boost converter chip U1 is electrically connected to the first end of the third resistor R3. The second plate of the second capacitor C2, the second plate of the fourth capacitor C4, the second plate of the fifth capacitor C5, the second end of the first resistor R1, the second end of the second resistor R2, the second end of the third resistor R3 and the ground pin of the boost converter chip U1 are all grounded.

[0078] Wherein, when the level of the enable pin EN1 of the boost converter chip U1 is high, the boost module 111 is enabled. In this way, the boost module 111 can boost the second voltage.

[0079] The boost converter chip U1 is used to boost the second voltage through the first inductor L1, the second diode D2 and the second capacitor C2 to obtain the first supply voltage.

[0080] The first feedback component 111-1 is used to transmit the first feedback voltage to the boost converter chip U1 according to the first supply voltage to adjust the first supply voltage.

[0081] In some examples, the boost module 111 may further include: a ninth capacitor C9 and a fifteenth resistor R15.

[0082] The first plate of the ninth capacitor C9 is electrically connected to the second end of the first inductor L1. The second plate of the ninth capacitor C9 is electrically connected to the first end of the fifteenth resistor R15. The second end of the fifteenth resistor R15 is grounded.

[0083] In some examples, the first feedback component 111-1 may include: a sixteenth resistor R16 and a seventeenth resistor R17.

[0084] The first end of the sixteenth resistor R16 is electrically connected to the cathode of the first diode D1, the second end of the sixteenth resistor R16 is electrically connected to the first end of the seventeenth resistor R17, the feedback pin FB1 of the boost converter chip U1 is electrically connected between the second end of the sixteenth resistor R16 and the first end of the seventeenth resistor R17, and the second end of the seventeenth resistor R17 is grounded.

[0085] When the first voltage V-12V is equal to or greater than the first threshold voltage, the first diode D1 conducts, causing the first voltage V-12V to be output to the output terminal VOUT of the power supply voltage output circuit 110, so that the power supply voltage output circuit 110 can output a third power supply voltage. That is to say, the third power supply voltage is obtained by outputting the first voltage V-12V through the power supply voltage output circuit 110. Thus, the buck circuit 130 can step down the third power supply voltage to supply power to the circuit breaker.

[0086] When the first voltage V-12V is less than the first threshold voltage, the first diode D1 is cut off. When enabled, the boost module 111 can step up the second voltage to obtain a first power supply voltage, enabling the power supply voltage output circuit 110 to output the first power supply voltage. That is to say, the first power supply voltage is obtained by outputting the second voltage through the power supply voltage output circuit 110. Thus, the buck circuit 130 can step down the first power supply voltage to supply power to the circuit breaker.

[0087] Based on the description of the above embodiments, an exemplary possible implementation manner of the detection circuit 120. Figure 3 Shows Figure 1 The structural schematic diagram of the detection circuit in. As Figure 3 shown, the detection circuit 120 may include: a first transistor Q1, a fourth resistor R4, a fifth resistor R5, and a sixth resistor R6.

[0088] The first end of the fourth resistor R4 is used to connect to the first voltage V-12V, the second end of the fourth resistor R4 is electrically connected to the first end of the fifth resistor R5, the gate terminal of the first transistor Q1 is electrically connected between the second end of the fourth resistor R4 and the first end of the fifth resistor R5, the source terminal of the first transistor Q1 is used to connect to the power supply voltage VCC, the drain terminal of the first transistor Q1 is electrically connected to the first end of the sixth resistor R6, the enable terminal of the power supply voltage output circuit 110 is electrically connected between the second end of the first transistor Q1 and the first end of the sixth resistor R6, and the second ends of the fifth resistor R5 and the sixth resistor R6 are both grounded.

[0089] Among them, the power supply voltage VCC is, for example, 3.3V.

[0090] When the first voltage V - 12V is equal to or greater than the first threshold voltage, the voltage Vin_DET obtained after dividing the voltage of the first voltage V - 12V through the fourth resistor R4 and the fifth resistor R5 is, for example, around 3.3V, making the drain terminal voltage of the first transistor Q1 the voltage Vin_DET. In this way, the first transistor Q1 is turned off, causing the enable signal output by the detection circuit 120 to be at a low level, such that the power supply voltage output circuit 110 cannot operate properly.

[0091] When the first voltage V - 12V is less than the first threshold voltage, the voltage Vin_DET is less than 3.3V, making the first transistor Q1 conduct. In this way, the enable signal output by the detection circuit 120 is converted from a low level to a high level, enabling the power supply voltage output circuit 110 to operate properly.

[0092] Based on the description of the above embodiments, by way of example, a possible implementation of the charging circuit 140. Figure 4 Shows Figure 1 The structural schematic diagram of the charging circuit in Figure 4 As shown, the charging circuit 140 may include: a detection module 141, a control module 142, a first current-limiting resistor Rs1, a second current-limiting resistor Rs2, a second transistor Q2, and a first triode VT.

[0093] The first end of the first current-limiting resistor Rs1 and the emitter of the first triode VT are both electrically connected to the output terminal VOUT of the power supply voltage output circuit 110. The second end of the first current-limiting resistor Rs1 is electrically connected to the drain terminal of the second transistor Q2. The source terminal of the second transistor Q2 and the input terminal of the detection module 141 are both electrically connected to the charging terminal V_SuperCAP of the power supply voltage output circuit 110. The gate terminal of the second transistor Q2 is electrically connected to the first end of the second current-limiting resistor Rs2. The output terminal of the detection module 141 is electrically connected to the first end of the control module 142. The second end of the control module 142 is electrically connected between the second end of the first current-limiting resistor Rs1 and the drain terminal of the second transistor Q2. The third end of the control module 142 is electrically connected to the base of the first triode VT. The collector of the first triode VT and the second end of the second current-limiting resistor Rs2 are both electrically connected between the source terminal of the second transistor Q2 and the input terminal of the detection module 141.

[0094] The detection module 141 is configured to transmit a detection signal to the control module 142 when detecting that the second voltage is greater than the second threshold voltage.

[0095] The control module 142 is configured to control the first triode VT to conduct according to the detection signal, so as to stop the charging circuit 140 from charging the first capacitor C1.

[0096] In some examples, the charging circuit 140 may further include: a tenth capacitor C10, a ninth resistor R9, and a tenth resistor R10.

[0097] The first plate of the tenth capacitor C10 is electrically connected to the first end of the first current-limiting resistor Rs1. The first end of the ninth resistor R9 is electrically connected to the collector of the first triode VT. The second end of the ninth resistor R9 is electrically connected to the second end of the second current-limiting resistor Rs2 and the first end of the tenth resistor R10 respectively. The second end of the tenth resistor R10 is electrically connected between the source of the second transistor Q2 and the input end of the detection module 141.

[0098] In some examples, the detection module 141 may include: an eleventh resistor R11 and a twelfth resistor R12.

[0099] The first end of the eleventh resistor R11 is electrically connected to the charging terminal V_SuperCAP of the power supply voltage output circuit 110. The second end of the eleventh resistor R11 is electrically connected to the first end of the twelfth resistor R12. The first end of the control module 142 is electrically connected between the second end of the eleventh resistor R11 and the first end of the twelfth resistor R12. The second end of the twelfth resistor R12 is grounded.

[0100] Wherein, Ua = Ucap*r12 / (r11 + r12), Ua is the voltage at point A, Ucap is the voltage at the charging terminal V_SuperCAP of the power supply voltage output circuit 110, that is, the voltage on the first capacitor C1, r11 is the resistance value of the eleventh resistor R11, and r12 is the resistance value of the twelfth resistor R12.

[0101] In some examples, the control module 142 may include: a seventh resistor R7, an eighth resistor R8, and a controller U2.

[0102] The first end of the seventh resistor R7 is electrically connected between the second end of the first current-limiting resistor Rs1 and the drain of the second transistor Q2. The second end of the seventh resistor R7 is electrically connected to the first end of the eighth resistor R8. The second end of the eighth resistor R8 is electrically connected to the second end of the controller U2. The first end of the controller U2 is electrically connected to the output end of the detection module 141. The base of the first triode VT is electrically connected between the second end of the seventh resistor R7 and the first end of the eighth resistor R8. The third end of the controller U2 is grounded.

[0103] Referring to Figure 5 , Figure 5 shows Figure 4 the schematic structural diagram of the controller in the charging circuit in Figure 5As shown, the controller U2 may include: a comparator CMP and a second triode K.

[0104] Among them, the power supply terminal CATHODE of the comparator is the second terminal of the controller U2, the first input terminal REF of the comparator is the first terminal of the controller U2, and the ground terminal of the comparator CMP is the third terminal of the controller U2.

[0105] When the first voltage V - 12V is equal to or greater than the first threshold voltage, the first triode VT is cut off, causing the second transistor Q2 to conduct. In this way, the third supply voltage charges the first capacitor C1 through the first current limiting resistor Rs1. When the voltage on the first capacitor C1 exceeds the second threshold voltage, the voltage at the first terminal, i.e., the REF terminal, of the controller U2 exceeds the second threshold voltage, and the controller U2 conducts, making the base voltage of the first triode VT lower than the emitter voltage. In this way, the first triode VT conducts, and the level at the gate terminal of the second transistor Q2 becomes high, causing the second transistor Q2 to be cut off, so that the charging circuit 140 stops charging the first capacitor C1, avoiding the phenomenon of shortened life of the first capacitor C1 caused by overcharging.

[0106] Among them, the second threshold voltage is, for example, 2.5V.

[0107] Based on the description of the above embodiments, exemplarily, a possible implementation manner of the buck circuit 130. Figure 6 Shows Figure 1 the schematic structural diagram of the buck circuit in Figure 6 As shown, the buck circuit 130 may include: a buck converter chip U3, a filtering component 131, and a second feedback component 132.

[0108] The power supply pin IN of the buck converter chip U3 is electrically connected to the output terminal of the power supply voltage output circuit 110, the switch pin SW2 of the buck converter chip U3 is electrically connected to the input terminal of the filtering component 131, the output terminal of the filtering component 131 is respectively electrically connected to the input terminal of the second feedback component 132 and the power supply terminal of the microprocessor 200, and the output terminal of the second feedback component 132 is electrically connected to the feedback pin FB2 of the buck converter chip U3.

[0109] In some examples, the buck circuit 130 may further include: an eleventh capacitor C11.

[0110] The first plate of the eleventh capacitor C11 is electrically connected to the power supply pin IN of the buck converter chip U3, and the second plate of the eleventh capacitor C11 is grounded.

[0111] The buck converter chip U3 is used to convert the first supply voltage into a pulse voltage and transmit the pulse voltage to the filtering component 131.

[0112] A filtering component 131 for converting a pulsed voltage into a second supply voltage.

[0113] A second feedback component 132 for obtaining the second supply voltage from the filtering component 131 and transmitting a second feedback voltage to the buck converter chip U3 according to the second supply voltage to adjust the second supply voltage.

[0114] Among them, the working principle of the buck circuit 130 for bucking down the third supply voltage is similar to that for bucking down the first supply voltage, so it will not be elaborated here.

[0115] In some examples, the filtering component 131 may include: a second inductor L2, a sixth capacitor C6, a seventh capacitor C7, and an eighth capacitor C8.

[0116] The first end of the second inductor L2 is electrically connected to the switch pin SW2 of the buck converter chip U3, and the second end of the second inductor L2 is respectively electrically connected to the first plate of the sixth capacitor C6, the first plate of the seventh capacitor C7, the first plate of the eighth capacitor C8, and the input end of the second feedback component 132.

[0117] In some examples, the second feedback component 132 may include: a thirteenth resistor R13 and a fourteenth resistor R14.

[0118] The first end of the thirteenth resistor R13 is electrically connected to the output end of the filtering component 131, the second end of the thirteenth resistor R13 is electrically connected to the first end of the fourteenth resistor R14, the feedback pin FB2 of the buck converter chip U3 is electrically connected between the second end of the thirteenth resistor R13 and the first end of the fourteenth resistor R14, and the second end of the fourteenth resistor R14 is grounded.

[0119] Among them, the stability of the second supply voltage can be ensured by the filtering component 131.

[0120] In addition, the buck circuit 130 in this application is implemented in a specific implementation manner of a buck converter BUCK, which can be applicable to a wide voltage operating range (for example, 7 - 40V), has high conversion efficiency, a small volume, and better electromagnetic compatibility performance.

[0121] The embodiment of this application also provides a circuit breaker, which includes: a microprocessor 200, a memory 300, and the power supply circuit 100 provided by the embodiment of this application.

[0122] The output end of the power supply circuit 100 is respectively electrically connected to the power supply end of the microprocessor 200 and the power supply end of the memory 300.

[0123] Among them, the circuit breaker further includes a trip controller 400, and the trip controller 400 is electrically connected to the microprocessor 200.

[0124] The circuit breaker provided by the embodiment of the present application has the same beneficial effects as the power supply circuit provided by the embodiment of the present application, and will not be elaborated here.

[0125] Finally, it should be noted that the above embodiments are only specific implementation manners of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A power supply circuit, characterized in that, The power supply circuit is applied to a circuit breaker, and the circuit breaker includes: a microprocessor; the power supply circuit includes: a power supply voltage output circuit, a detection circuit, and a step-down circuit; The input end of the power supply voltage output circuit and the input end of the detection circuit are both used to connect to a first voltage. The enable end of the power supply voltage output circuit is electrically connected to the output end of the detection circuit. The output end of the power supply voltage output circuit is electrically connected to the input end of the step-down circuit. The output end of the step-down circuit is electrically connected to the power supply end of the microprocessor; The detection circuit is used to transmit an enable signal to the power supply voltage output circuit when it detects that the first voltage is less than a first threshold voltage, and the enable signal is used to enable the power supply voltage output circuit; The power supply voltage output circuit is used to boost a second voltage to obtain a first power supply voltage and transmit the first power supply voltage to the step-down circuit after being enabled when the first voltage is less than the first threshold voltage; The step-down circuit is used to step down the first power supply voltage to obtain a second power supply voltage and transmit the second power supply voltage to the microprocessor, so that the microprocessor stores fault information in a memory, and the fault information is used to characterize that the circuit breaker has a fault.

2. The circuit according to claim 1, wherein The power supply circuit further includes: a charging circuit; The input end of the charging circuit is electrically connected to the output end of the power supply voltage output circuit, and the output end of the charging circuit is electrically connected to the charging end of the power supply voltage output circuit; The power supply voltage output circuit is further used to transmit a third power supply voltage to the charging circuit when the first voltage is equal to or greater than the first threshold voltage; The charging circuit is used to charge a first capacitor in the power supply voltage output circuit according to the third power supply voltage, so that the power supply voltage output circuit uses the voltage on the first capacitor as the second voltage, and stops charging the first capacitor when the second voltage is greater than a second threshold voltage.

3. The circuit according to claim 2, wherein The power supply voltage output circuit includes: a first capacitor, a boosting module, and a first diode; The first plate of the first capacitor and the input end of the boosting module are both electrically connected to the output end of the charging circuit. The enable end of the boosting module is electrically connected to the output end of the detection circuit. The output end of the boosting module is electrically connected to the negative electrode of the first diode. The input end of the step-down circuit is electrically connected between the output end of the boosting module and the negative electrode of the first diode. The positive electrode of the first diode is used to connect to the first voltage; The boosting module is used to boost the second voltage to obtain the first power supply voltage after being enabled.

4. The circuit according to claim 3, wherein The boosting module includes: a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a second diode, a first inductor, a first resistor, a second resistor, a third resistor, a boost converter chip, and a first feedback component; The first end of the first inductor is electrically connected to the output end of the charging circuit. The second end of the first inductor is electrically connected to the positive electrode of the second diode. The negative electrode of the second diode and the first plate of the second capacitor are both electrically connected to the negative electrode of the first diode. The switching pin of the boost converter chip is electrically connected between the second end of the first inductor and the positive electrode of the second diode. The output pin of the boost converter chip and the input end of the first feedback component are both electrically connected between the negative electrode of the second diode and the negative electrode of the first diode. The enable pin of the boost converter chip is electrically connected to the output end of the detection circuit. The feedback pin of the boost converter chip is electrically connected to the output end of the first feedback component. The power pin of the boost converter chip is grounded through the third capacitor. The first pin of the boost converter chip is respectively electrically connected to the first plate of the fourth capacitor and the first end of the first resistor. The second pin of the boost converter chip is respectively electrically connected to the first plate of the fifth capacitor and the first end of the second resistor. The third pin of the boost converter chip is electrically connected to the first end of the third resistor. The second plate of the second capacitor, the second plate of the fourth capacitor, the second plate of the fifth capacitor, the second end of the first resistor, the second end of the second resistor, the second end of the third resistor, and the ground pin of the boost converter chip are all grounded; The boost converter chip is configured to boost the second voltage through the first inductor, the second diode, and the second capacitor to obtain the first supply voltage; The first feedback component is configured to transmit a first feedback voltage to the boost converter chip according to the first supply voltage to adjust the first supply voltage.

5. The circuit according to claim 2, wherein The detection circuit includes: a first transistor, a fourth resistor, a fifth resistor, and a sixth resistor; The first end of the fourth resistor is used to connect to the first voltage. The second end of the fourth resistor is electrically connected to the first end of the fifth resistor. The gate terminal of the first transistor is electrically connected between the second end of the fourth resistor and the first end of the fifth resistor. The source terminal of the first transistor is used to connect to the power supply voltage. The drain terminal of the first transistor is electrically connected to the first end of the sixth resistor. The enable end of the power supply voltage output circuit is electrically connected between the drain terminal of the first transistor and the first end of the sixth resistor. The second ends of the fifth resistor and the sixth resistor are both grounded.

6. The circuit according to claim 2, wherein The charging circuit includes: a detection module, a control module, a first current limiting resistor, a second current limiting resistor, a second transistor, and a first triode; The first end of the first current-limiting resistor and the emitter of the first triode are both electrically connected to the output end of the power supply voltage output circuit. The second end of the first current-limiting resistor is electrically connected to the drain end of the second transistor. The source end of the second transistor and the input end of the detection module are both electrically connected to the charging end of the power supply voltage output circuit. The gate end of the second transistor is electrically connected to the first end of the second current-limiting resistor. The output end of the detection module is electrically connected to the first end of the control module. The second end of the control module is electrically connected between the second end of the first current-limiting resistor and the drain end of the second transistor. The third end of the control module is electrically connected to the base of the first triode. The collector of the first triode and the second end of the second current-limiting resistor are both electrically connected between the source end of the second transistor and the input end of the detection module; The detection module is configured to transmit a detection signal to the control module when detecting that the second voltage is greater than the second threshold voltage; The control module is configured to control the first triode to conduct according to the detection signal, so that the charging circuit stops charging the first capacitor.

7. The circuit according to claim 6, wherein The control module includes: a seventh resistor, an eighth resistor, and a controller; The first end of the seventh resistor is electrically connected between the second end of the first current-limiting resistor and the drain end of the second transistor. The second end of the seventh resistor is electrically connected to the first end of the eighth resistor. The second end of the eighth resistor is electrically connected to the second end of the controller. The first end of the controller is electrically connected to the output end of the detection module. The base of the first triode is electrically connected between the second end of the seventh resistor and the first end of the eighth resistor. The third end of the controller is grounded.

8. The circuit according to any one of claims 1-7, characterized in that, The buck circuit includes: a buck converter chip, a filtering component, and a second feedback component; The power supply pin of the buck converter chip is electrically connected to the output end of the power supply voltage output circuit. The switching pin of the buck converter chip is electrically connected to the input end of the filtering component. The output end of the filtering component is respectively electrically connected to the input end of the second feedback component and the power supply end of the microprocessor. The output end of the second feedback component is electrically connected to the feedback pin of the buck converter chip; The buck converter chip is configured to convert the first power supply voltage into a pulse voltage and transmit the pulse voltage to the filtering component; The filtering component is configured to convert the pulse voltage into the second power supply voltage; The second feedback component is configured to obtain the second power supply voltage from the filtering component and transmit a second feedback voltage to the buck converter chip according to the second power supply voltage to adjust the second power supply voltage.

9. The circuit according to claim 8, wherein The filtering component includes: a second inductor, a sixth capacitor, a seventh capacitor, and an eighth capacitor; The first end of the second inductor is electrically connected to the switching pin of the buck converter chip, and the second end of the second inductor is electrically connected to the first plate of the sixth capacitor, the first plate of the seventh capacitor, the first plate of the eighth capacitor, and the input end of the second feedback component respectively.

10. A circuit breaker, characterized in that, Comprising: A microprocessor, a memory, and a power supply circuit as described in any one of claims 1-9; The output end of the power supply circuit is electrically connected to the power supply end of the microprocessor and the power supply end of the memory respectively.

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