Power supply monitoring protection circuit and power supply monitoring protection device

Abstract

The present application relates to the field of electronic technology, and in particular to a power supply monitoring and protection circuit and a power supply monitoring and protection device. The power supply monitoring and protection circuit includes: a power supply circuit, a power supply protection circuit and a voltage monitoring unit; the power supply circuit is used to receive a first voltage signal, and after processing the first voltage signal, output a second voltage signal; the power supply protection circuit is used to receive the second voltage signal output by the power supply circuit, and perform overcurrent and / or overvoltage protection on the second voltage signal; the voltage monitoring unit is used to collect the first voltage signal and the power supply voltage signals of multiple chips to be monitored, and respectively determine whether the voltage value of the first voltage signal and the power supply voltage signals of multiple chips to be monitored exceed a preset value, and if so, control the disconnection of the power supply of the corresponding chip to be monitored. The present application monitors the voltage value of each power supply signal in real time through the voltage monitoring unit, and responds accordingly according to the corresponding voltage fluctuation to protect the entire circuit system.

Description

Technical Field

[0001] The present application relates to the field of electronic technology, and in particular to a power supply monitoring and protection circuit and a power supply monitoring and protection device. Background Art

[0002] In order to ensure the working safety of electronic products and extend their working life, it is necessary to monitor and protect the power supply voltage and current of electronic products in real time.

[0003] Protecting electronic products mainly protects the components in the electronic product circuits from damage under conditions such as overvoltage, overcurrent, surge, and electromagnetic interference, so as to extend the service life of the electronic products. Figure 1 This is a schematic diagram of a power supply protection circuit structure provided in the related art, see Figure 1 As shown, the power supply 10 is used to power the monitoring module 20. The monitoring module 20 continuously monitors the supply voltage of the control module 30. When the monitoring module 20 detects that the supply voltage of the control module 20 is higher or lower than a set value, the monitoring module 20 outputs a reset signal to the control module 30 to reset the control module 30, thereby preventing damage to the control module 30. Typically, a circuit system also includes multiple other functional chips. For example, a general circuit system also includes a memory chip, various sensor chips, various communication interface chips, etc., and the protection circuits provided by related technologies cannot perform the power supply voltage monitoring and protection functions for these chips. Summary of the Invention

[0004] The present application provides a power supply monitoring and protection circuit and a power supply monitoring and protection device, which realize the monitoring and protection of the power supply voltage of multiple functional chips in a circuit system.

[0005] In a first aspect, the present application provides a power supply monitoring and protection circuit, the power supply monitoring and protection circuit comprising: a power supply circuit, a power protection circuit and a voltage monitoring unit;

[0006] The power supply circuit is configured to receive a first voltage signal, process the first voltage signal, and output a second voltage signal;

[0007] The power protection circuit is configured to receive the second voltage signal output by the power supply circuit, perform overcurrent and / or overvoltage protection on the second voltage signal, and output a third voltage signal to the voltage monitoring unit, wherein the third voltage signal is used to power the voltage monitoring unit;

[0008] The voltage monitoring unit is used to collect the first voltage signal and the power supply voltage signals of multiple chips to be monitored, and respectively determine whether the voltage value of the first voltage signal and the power supply voltage signals of the multiple chips to be monitored exceed preset values. If so, output a power supply disconnection signal, and the power supply disconnection signal is used to control the disconnection of the power supply pin of the corresponding chip to be monitored.

[0009] In one possible design, the power supply monitoring and protection circuit also includes an interrupt reset chip, which is used to collect the voltage value of the first voltage signal and determine whether the voltage value of the first voltage signal is within a preset range. If not, it outputs a first reset signal to the voltage monitoring unit; the first reset signal is used to control the voltage monitoring unit to perform a reset operation.

[0010] In one possible design, the interrupt reset chip is also used to receive an input system reset signal and output a second reset signal to the voltage monitoring unit according to the system reset signal. The second reset signal is used to control the voltage monitoring unit to perform a reset operation.

[0011] In one possible design, the chip to be monitored includes one or more of a sensor chip, a communication interface chip, and a storage chip.

[0012] In one possible design, the power supply protection circuit is used to monitor whether the current value of the second voltage signal exceeds a preset value, and output a first flag signal to the voltage monitoring unit based on the monitoring result. The first flag signal includes two flag states, and the two flag states of the first flag signal respectively indicate that the current value of the second voltage signal is in an overcurrent state and a non-overcurrent state.

[0013] In one possible design, the power supply protection circuit is used to monitor whether the voltage value of the second voltage signal exceeds a preset value, and output a second flag signal to the voltage monitoring unit based on the monitoring result, and the second flag signal includes two flag states, and the two flag states of the second flag signal respectively indicate that the voltage value of the second voltage signal is in an overvoltage state and a non-overvoltage state.

[0014] In a possible design, at least one first voltage sampling circuit is further included; the first voltage sampling circuit includes a first resistor and a second resistor;

[0015] The first end of the first resistor is used to receive the first voltage signal or the second voltage signal, the second end of the first resistor is connected to the first end of the second resistor, the second end of the second resistor is grounded, the first end of the second resistor is a sampling output end, and the first end of the second resistor is connected to the voltage sampling terminal on the voltage monitoring unit.

[0016] In one possible design, a second voltage sampling circuit is further included, wherein the second voltage sampling circuit includes a third resistor and a fourth resistor;

[0017] The first end of the third resistor is used to receive the first voltage signal, the second end of the third resistor is connected to the first end of the fourth resistor, and the second end of the fourth resistor is grounded; the first end of the fourth resistor is a sampling output end, and the first end of the fourth resistor is connected to the voltage sampling terminal of the interrupt reset chip.

[0018] In a possible design, it also includes a first capacitor and a fifth resistor, the first end of the fifth resistor is connected to the current output terminal of the power protection circuit, the second end of the fifth resistor is grounded, and the first capacitor is connected in parallel at both ends of the fifth resistor.

[0019] In a second aspect, the present application also provides a power supply monitoring and protection device, which includes a power supply monitoring and protection circuit as described in any one of the above items.

[0020] With the power supply monitoring and protection circuit provided in the first aspect, the voltage monitoring unit U1 monitors the voltage values ​​of each power supply signal in real time, dynamically identifies voltage fluctuations anywhere in the circuit system, and responds accordingly. This enables real-time monitoring of the power supply to each external chip and the power supply at each level within the board, protecting the entire circuit system.

[0021] The beneficial effects provided in the above-mentioned second aspect and the various possible designs of the above-mentioned second aspect can be referred to the beneficial effects brought about by the above-mentioned first aspect and the various possible implementation methods of the first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of a power supply protection circuit structure provided in the related art;

[0023] Figure 2 A schematic diagram of the power supply monitoring and protection circuit structure provided in an embodiment of the present application. DETAILED DESCRIPTION

[0024] 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.

[0025] 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.

[0026] 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.

[0027] In the related art, when the circuit system is powered on, the monitoring module will continuously monitor the power supply voltage of the control module. Depending on the application scenario of the product, the set value corresponding to the power supply voltage monitored by the monitoring module may be different. When the power supply voltage of the control module monitored by the monitoring module is lower than the set voltage value, the monitoring module will output a low level to the reset pin of the control module, so that the control module is reset, thereby protecting the safety of the circuit system. Generally, the circuit system also includes multiple other functional chips. Generally, the circuit system also includes storage chips, various sensor chips, various communication interface chips, etc. In the related art, after the control module is reset, the other functional chips are still in normal power supply mode. Under this working condition, if the power supply voltage of other functional chips is abnormal, it cannot be monitored in time and protected. Therefore, the protection circuit of the related art still has certain defects.

[0028] In order to overcome the technical defects existing in the above-mentioned related technologies, the present application provides a power supply monitoring and protection circuit and a power supply monitoring and protection device, which includes: a power supply circuit, a power protection circuit and a voltage monitoring unit; the power supply circuit is used to receive a first voltage signal, and the voltage monitoring unit is used to collect the first voltage signal and the power supply voltage signals of multiple chips to be monitored, and respectively determine whether the voltage value of the first voltage signal and the power supply voltage signals of multiple chips to be monitored exceed the preset value. If so, a power supply disconnection signal is output to control the disconnection of the power supply pin of the corresponding chip to be monitored, thereby realizing power supply voltage monitoring and protection of multiple functional chips.

[0029] Figure 2 For a schematic diagram of the power supply monitoring and protection circuit structure provided in the embodiment of this application, please refer to Figure 2 As shown, the power supply monitoring and protection circuit includes: a power supply circuit U4, a power protection circuit U2 and a voltage monitoring unit U1.

[0030] The power supply circuit U4 is used to receive a first voltage signal VIN and output a second voltage signal after processing the first voltage signal VIN. The first voltage signal VIN can be understood as the total input voltage signal of the circuit. The power supply circuit U4 processes the total input voltage signal and then supplies power to each chip in the circuit. The second voltage signal is the voltage signal output by the power supply circuit after processing. The second voltage signal is generally used to power each functional module. The power supply protection circuit U2 is used to receive the second voltage signal output by the power supply circuit U4 and perform overcurrent and / or overvoltage protection on the second voltage signal to avoid damage to subsequent devices due to excessive current or excessive voltage. At the same time, the power supply protection circuit U2 also outputs a third voltage signal to the voltage monitoring unit U1. The third voltage signal is used to power the voltage monitoring unit U1 to meet the power supply requirements of the voltage monitoring unit U1. The voltage monitoring unit U1 is used to collect the first voltage signal VIN and the power supply voltage signals of multiple chips to be monitored, and respectively determine whether the voltage value of the first voltage signal VIN and the power supply voltage signals of multiple chips to be monitored exceed preset values. If so, it outputs a power supply disconnection signal. The power supply disconnection signal is used to control the disconnection of the power supply pin of the corresponding chip to be monitored, so that the corresponding functional chip stops working, thereby avoiding damage to the device.

[0031] It can be understood that in actual operating conditions, the power supply circuit U4 processes the input first voltage signal VIN and outputs a second voltage signal to power each functional module, which can be understood as a chip. In some application scenarios, based on power supply requirements, multiple power supply voltages with different voltage values ​​can be output simultaneously to meet the power supply requirements of different functional modules. For example, by outputting two voltage signals of 12V and 3.3V to power different functional modules.

[0032] In some embodiments, the power supply circuit U4 includes a rectifier circuit, a voltage conversion circuit, and the like. When the input first voltage signal VIN is alternating current (AC), the rectifier circuit can convert the input AC power into direct current (DC). The voltage conversion circuit can convert the voltage value of the first voltage signal VIN to output a power supply voltage signal with a voltage value that matches the output voltage value.

[0033] It can be understood that in order to achieve overcurrent and overvoltage protection for the subsequent chip, the second voltage signal output by the power supply circuit U4 is first input into the power protection circuit U2. The power protection circuit U2 can perform overcurrent and overvoltage protection on the second voltage signal to ensure the safety of the subsequent devices.

[0034] In some embodiments, the power protection circuit U2 includes an overcurrent protection circuit to perform overcurrent detection on the input second voltage signal. When the current value is too large or too small, a first flag signal is output to the voltage monitoring unit U1. The first flag signal includes two flag states, and the two flag states of the first flag signal respectively indicate that the current value of the second voltage signal is in an overcurrent state and a non-overcurrent state. For example, when the current value does not meet the set value, that is, it is greater than the maximum set value or less than the minimum set value, the state of the first flag signal is output as 1. Otherwise, the state of the first flag signal is output as 0. When the voltage monitoring unit U1 receives the first flag signal with a state of 1, it determines that the current value of the current power supply signal does not meet the requirements.

[0035] In some embodiments, the power supply protection circuit U2 includes an overvoltage protection circuit, which is used to monitor whether the voltage value of the second voltage signal exceeds a preset value, and output a second flag signal to the voltage monitoring unit U1 based on the monitoring result. The second flag signal includes two flag states, and the two flag states of the second flag signal respectively indicate that the voltage value of the second voltage signal is in an overvoltage state and a non-overvoltage state.

[0036] In some embodiments, the power protection circuit U2 includes both an overcurrent protection circuit and an overvoltage protection circuit to perform overcurrent and overvoltage detection on the input second voltage signal, thereby providing overvoltage and overcurrent protection for subsequent devices.

[0037] In one application scenario, when a device or functional module in the subsequent stage fails, causing the current flowing through the power protection circuit U2 to exceed the set value, the power protection circuit U2 outputs a first flag signal to the voltage monitoring unit U1 to cut off the power supply of the corresponding functional module or cut off the power supply of the entire circuit system, thereby achieving the purpose of overcurrent protection of the circuit system.

[0038] In one application scenario, when a device or functional module in the subsequent stage fails, causing the voltage value flowing through the power protection circuit U2 to exceed the set value, the power protection circuit U2 outputs a first flag signal to the voltage monitoring unit U1 to cut off the power supply of the corresponding functional module or cut off the power supply of the entire circuit system, thereby achieving the purpose of overvoltage protection of the circuit system.

[0039] When the power protection circuit U2 detects that the voltage and current values ​​of the power supply signal have returned to normal, it outputs a first flag signal indicating a normal state to the voltage monitoring unit U1. The voltage monitoring unit U1 then controls the circuit system to resume power supply to restore the normal working mode.

[0040] In some embodiments, the chip to be monitored includes a sensor chip, a communication interface chip, and a memory chip. For example, the chip to be detected includes a temperature monitoring chip, an RS485 communication interface chip, and a memory chip. For example, see Figure 2 As shown in FIG, the circuit system in this embodiment includes a sensor chip U5, an external communication interface chip U6 and a storage chip U7.

[0041] In some embodiments, the power supply monitoring and protection circuit further includes an interrupt reset chip U3, which is used to collect the voltage value of the first voltage signal VIN and determine whether the voltage value of the first voltage signal VIN is within a preset range. If not, the interrupt reset chip U3 outputs a first reset signal to the voltage monitoring unit U1; the first reset signal is used to control the voltage monitoring unit U1 to perform a reset operation to cut off the power supply circuit to the voltage monitoring unit U1 to protect the voltage monitoring unit U1. When the interrupt reset chip U3 detects that the voltage value of the first voltage signal VIN has returned to normal, it outputs a first reset signal in a different state to restore the circuit system to normal working mode.

[0042] In some embodiments, after receiving the first reset signal output by the interruption reset chip U3 , the voltage monitoring unit U1 further outputs a control signal to control the power supply circuit U4 to be disconnected to prevent subsequent devices from being damaged.

[0043] In some embodiments, the interrupt reset chip U3 is also used to receive an input system reset signal NRST, and output a second reset signal to the voltage monitoring unit U1 according to the system reset signal NRST. The second reset signal is used to control the voltage monitoring unit U1 to perform a reset operation. For example, when an external interrupt requires resetting the entire circuit system, the system reset signal NRST can be input to the interrupt reset chip U3, and the voltage monitoring unit U1 can reset the entire circuit system according to the system reset signal NRST to stop working. It can be understood that the above-mentioned first reset signal, system reset signal NRST and second reset signal can be level signals or pulse signals. For example, outputting a high-level signal indicates that the reset signal is valid, and outputting a low-level signal indicates that the reset signal is invalid.

[0044] It is understandable that the above-mentioned setting values ​​in this application can be set to different values ​​according to specific application scenarios.

[0045] In some embodiments, the voltage monitoring unit U1 is an integrated circuit chip with multiple ADC sampling channels. Generally, the voltage monitoring unit U1 can be an integrated circuit with at least a 16-bit ADC peripheral, which can significantly improve sampling accuracy and control errors within a few millivolts. For example, the voltage monitoring unit U1 can be an FPGA (Field Programmable Gate Array) with multiple ADC sampling channels; or, the voltage monitoring unit U1 can be a DSP (Digital Signal Processing) with multiple ADC sampling channels; or, the voltage monitoring unit U1 can be a CPU (Central Processing Unit) with multiple ADC sampling channels; or, the voltage monitoring unit U1 can be an MCU (Microcontroller Unit) with multiple ADC sampling channels.

[0046] In this embodiment, the ADC detection period of the voltage monitoring unit U1 can be set to 10KHz, so as to monitor the voltage value of each power supply in real time.

[0047] Please continue to see Figure 1 As shown, in some embodiments, the power supply monitoring and protection circuit further includes at least one first voltage sampling circuit; the first voltage sampling circuit includes a first resistor R1 and a second resistor R2; the first end of the first resistor R1 is used to receive a first voltage signal, the second end of the first resistor R1 is connected to the first end of the second resistor R2, the second end of the second resistor R2 is grounded, the first end of the second resistor R2 is a sampling output end, and the first end of the second resistor R2 is connected to the ADC voltage sampling terminal on the voltage monitoring unit U1. Resistors R1 and R2 are voltage-dividing resistors that divide the external input first voltage signal VIN and various internal board-level voltages and then provide them to the ADC voltage sampling pin of the voltage monitoring unit U1, so that the voltage monitoring unit U1 can collect the voltage value of the first voltage signal VIN.

[0048] In some embodiments, the power supply monitoring and protection circuit includes two first voltage sampling circuits, wherein one first voltage sampling circuit is used to collect the voltage value of the first voltage signal VIN, and the other first voltage sampling circuit is used to collect the power supply voltage VDD for each chip.

[0049] In this embodiment, the ADC pin software of the voltage monitoring unit U1 is used to sample the power supply of each chip inside and outside the board, thereby improving the voltage sampling accuracy and performing real-time monitoring of the sampled voltage value, thereby improving the monitoring accuracy and response speed of the circuit system and improving the safety of the circuit system.

[0050] The ADC pins on the voltage monitoring unit U1 collect real-time voltage data from the power supplies of various chips within the board and externally. By monitoring these voltages in real time, the voltage monitoring unit U1 dynamically identifies voltage fluctuations anywhere in the circuit system and responds accordingly. This allows for real-time monitoring of the power supply to various external chips and the power supply levels within the board, protecting the entire circuit system.

[0051] In this embodiment, the voltage monitoring unit U1 uses a combination of software and hardware to collect and monitor the voltages in the circuit. By comparing the collected voltage with the set threshold, it monitors whether the power supply voltages at all levels in the board are normal. When the voltage value collected by the ADC on the board is greater than or less than the threshold, the software starts to prompt that the voltage is abnormal. When the voltage in the board continues to be abnormal, the software works to output a control signal to cut off the working voltage of the circuit to protect the circuit. For example, when the power supply voltage of a chip in the board continues to be abnormal, the software works to output a control signal to control the power supply pin of the chip to be cut off to protect the circuit system.

[0052] In some embodiments, when the voltage monitoring unit U1 detects an abnormal supply voltage on a particular chip, it responds by shutting off the power supply to the corresponding chip and outputting an alarm signal or displaying an alarm message. This alarm signal can be uploaded to the control center for prompt action. This combination of software and hardware allows for real-time monitoring of the power supply at all levels of the system to protect the entire circuit.

[0053] Please continue to see Figure 1 As shown, in some embodiments, the power supply monitoring and protection circuit further includes a second voltage sampling circuit, which includes a third resistor R3 and a fourth resistor R4. The first end of the third resistor R3 is used to receive the first voltage signal VIN, the second end of the third resistor R3 is connected to the first end of the fourth resistor R4, and the second end of the fourth resistor R4 is grounded. The first end of the fourth resistor R4 is a sampling output end, and the first end of the fourth resistor R4 is connected to the voltage sampling terminal of the interrupt reset chip U3, so that the interrupt reset chip U3 can collect the first voltage signal VIN.

[0054] Please continue to see Figure 1 As shown, in some embodiments, the power supply monitoring protection circuit further includes a first capacitor C1 and a fifth resistor R5, wherein the first end of the fifth resistor R5 is connected to the current output terminal of the power supply protection circuit U2, the second end of the fifth resistor is grounded, and the first capacitor is connected in parallel to both ends of the fifth resistor. After the second voltage signal is processed by the overvoltage and overcurrent protection of the power supply protection circuit U2, power is supplied to each subsequent chip. The overcurrent protection current threshold of the power supply protection circuit U2 is determined by the fifth resistor R5. The voltage threshold of the overvoltage protection of the power supply protection circuit U2 is determined according to the supply voltage of each chip.

[0055] This embodiment also provides a power supply monitoring and protection device, which includes the power supply monitoring and protection circuits provided in the above embodiments. It is understood that the power supply monitoring and protection device may also include some related hardware, such as an outer shell, a circuit board, a power supply, and a communication interface, which will not be described in detail here.

[0056] Finally, it should be noted that the above embodiments are merely specific implementations of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A power supply monitoring and protection circuit, characterized in that: The power supply monitoring and protection circuit includes: a power supply circuit, a power protection circuit and a voltage monitoring unit; The power supply circuit is configured to receive a first voltage signal, process the first voltage signal, and output a second voltage signal; The power protection circuit is configured to receive the second voltage signal output by the power supply circuit, perform overcurrent and / or overvoltage protection on the second voltage signal, and output a third voltage signal to the voltage monitoring unit, wherein the third voltage signal is used to power the voltage monitoring unit; The voltage monitoring unit is used to collect the first voltage signal and the power supply voltage signals of multiple chips to be monitored, and respectively determine whether the voltage value of the first voltage signal and the power supply voltage signals of the multiple chips to be monitored exceed preset values. If so, a power supply disconnection signal is output, and the power supply disconnection signal is used to control the disconnection of the power supply pin of the corresponding chip to be monitored; the power supply monitoring protection circuit also includes an interrupt reset chip, and the interrupt reset chip is used to collect the voltage value of the first voltage signal and determine whether the voltage value of the first voltage signal is within a preset range. If not, a first reset signal is output to the voltage monitoring unit; the first reset signal is used to control the voltage monitoring unit to perform a reset operation; The interrupt reset chip is further used to receive an input system reset signal and output a second reset signal to the voltage monitoring unit according to the system reset signal. The second reset signal is used to control the voltage monitoring unit to perform a reset operation.

2. The power supply monitoring and protection circuit according to claim 1, characterized in that: The chip to be monitored includes one or more of a sensor chip, a communication interface chip and a storage chip.

3. The power supply monitoring and protection circuit according to claim 1, characterized in that: The power supply protection circuit is used to monitor whether the current value of the second voltage signal exceeds a preset value, and output a first flag signal to the voltage monitoring unit based on the monitoring result, wherein the first flag signal includes two flag states, and the two flag states of the first flag signal respectively indicate that the current value of the second voltage signal is in an overcurrent state and a non-overcurrent state.

4. The power supply monitoring and protection circuit according to claim 3, characterized in that: The power supply protection circuit is used to monitor whether the voltage value of the second voltage signal exceeds a preset value, and output a second flag signal to the voltage monitoring unit according to the monitoring result, wherein the second flag signal includes two flag states, and the two flag states of the second flag signal respectively indicate that the voltage value of the second voltage signal is in an overvoltage state and a non-overvoltage state.

5. The power supply monitoring and protection circuit according to claim 1, characterized in that: It also includes at least one first voltage sampling circuit; the first voltage sampling circuit includes a first resistor and a second resistor; The first end of the first resistor is used to receive the first voltage signal or the second voltage signal, the second end of the first resistor is connected to the first end of the second resistor, the second end of the second resistor is grounded, the first end of the second resistor is a sampling output end, and the first end of the second resistor is connected to the voltage sampling terminal on the voltage monitoring unit.

6. The power supply monitoring and protection circuit according to claim 1, characterized in that: Also included is a second voltage sampling circuit, wherein the second voltage sampling circuit includes a third resistor and a fourth resistor; The first end of the third resistor is used to receive the first voltage signal, the second end of the third resistor is connected to the first end of the fourth resistor, and the second end of the fourth resistor is grounded; the first end of the fourth resistor is a sampling output end, and the first end of the fourth resistor is connected to the voltage sampling terminal of the interrupt reset chip.

7. The power supply monitoring and protection circuit according to claim 1, characterized in that: It also includes a first capacitor and a fifth resistor, wherein the first end of the fifth resistor is connected to the current output terminal of the power protection circuit, the second end of the fifth resistor is grounded, and the first capacitor is connected in parallel at both ends of the fifth resistor.

8. A power supply monitoring and protection device, characterized in that: The invention comprises a power supply monitoring and protection circuit as described in any one of claims 1 to 7.

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