NOR Flash chip voltage abnormity protection circuit

Abstract

The invention discloses a voltage abnormity protection circuit for a NOR Flash chip, and relates to the field of safety protection, and the voltage abnormity protection circuit for the NOR Flash chip comprises a power supply module which is used for supplying working voltage to a temperature detection module, an overvoltage detection module and an undervoltage detection module; the temperature detection module is used for detecting whether the temperature of the NOR Flash chip is abnormal or not and disconnecting the loop where the switch control module is located when the temperature is abnormal; the overvoltage detection module is used for detecting whether the voltage of the NOR Flash chip is overvoltage or not and disconnecting the loop where the switch control module is located when the voltage is overvoltage; the method has the advantages that whether a loop of the processor signal data interface and the NOR Flash chip data signal interface is disconnected or not is selectively controlled by detecting information such as the temperature and the voltage of the NOR Flash chip, and the situation that communication transmission information is abnormal due to the fact that the NOR Flash chip sends a wrong instruction in an unstable state is avoided.

Description

Technical Field

[0001] The invention relates to the field of safety protection, and in particular to a NOR Flash chip voltage abnormality protection circuit. Background Art

[0002] NOR Flash chip, also known as NOR flash memory, is a non-volatile memory commonly used in embedded systems and storage devices such as smartphones, printers, digital cameras, TWS headphones, AMOLED screens, etc. In these devices, NOR Flash is used to store program code and firmware to ensure the normal operation of the device.

[0003] When the product loses power, the process of the voltage gradually decreasing from the normal value to 0 may cause the NOR Flash chip to be in an unstable state. In an unstable state, the NOR Flash chip may send erroneous instructions, causing abnormal communication transmission information, which needs to be improved. Summary of the invention

[0004] The object of the present invention is to provide a NOR Flash chip voltage abnormality protection circuit to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A NOR Flash chip voltage abnormality protection circuit, comprising:

[0007] A power supply module, used to supply working voltage to the temperature detection module, the overvoltage detection module, and the undervoltage detection module;

[0008] The temperature detection module is used to detect whether the temperature of the NOR Flash chip is abnormal. If it is abnormal, the circuit where the switch control module is located is disconnected;

[0009] Overvoltage detection module, used to detect whether the voltage of NOR Flash chip is overvoltage, and disconnect the circuit where the switch control module is located when overvoltage occurs;

[0010] An undervoltage detection module is used to detect whether the voltage of the NOR Flash chip is undervoltage, and disconnect the circuit where the switch control module is located when undervoltage occurs;

[0011] The switch control module is used to establish the communication between the processor data signal and the NOR Flash chip data signal when the loop is turned on;

[0012] The output end of the power supply module is connected to the input end of the temperature detection module, the input end of the overvoltage detection module, and the input end of the undervoltage detection module. The output end of the temperature detection module is connected to the first input end of the switch control module. The output end of the overvoltage detection module is connected to the second input end of the switch control module. The output end of the undervoltage detection module is connected to the third input end of the switch control module.

[0013] As a further solution of the present invention: the power supply module includes a first resistor, a first capacitor, a second capacitor, and a voltage regulator. A 12V voltage is introduced into one end of the first resistor, the other end of the first resistor is connected to one end of the first capacitor and the input end of the voltage regulator, the other end of the first capacitor is grounded, the ground end of the voltage regulator is grounded, the output end of the voltage regulator is connected to one end of the second capacitor, the input end of the temperature detection module, the input end of the overvoltage detection module, and the input end of the undervoltage detection module, and the other end of the second capacitor is grounded.

[0014] As a further solution of the present invention: the temperature detection module includes a temperature sensor, a second resistor, a first potentiometer, a third capacitor, a first diode, and a second diode. The working voltage is introduced into the power supply end of the temperature sensor, the ground end of the temperature sensor is grounded, the output end of the temperature sensor is connected to one end of the second resistor, the other end of the second resistor is connected to one end of the first potentiometer, the other end of the first potentiometer is connected to one end of the third capacitor and the cathode of the first diode, the other end of the third capacitor is grounded, the anode of the first diode is connected to the anode of the second diode, and the cathode of the second diode is connected to the first input end of the switch control module.

[0015] As a further solution of the present invention: the overvoltage detection module includes:

[0016] The voltage division detection unit is used to detect whether the voltage of the NOR Flash chip is over-voltage, and provide a driving signal to the isolation feedback unit when over-voltage occurs;

[0017] The isolation feedback unit is used to stop outputting the voltage signal supplied to the switch control module when working;

[0018] The output end of the voltage division detection unit is connected to the first input end of the isolation feedback unit, the second input end of the isolation feedback unit is connected to the output end of the power supply module, and the output end of the isolation feedback unit is connected to the second input end of the switch control module.

[0019] As a further solution of the present invention: the voltage divider detection unit includes a fourth resistor, a fourth capacitor, a second potentiometer, a fifth resistor, and a third diode. One end of the fourth resistor introduces the NOR Flash chip voltage, the other end of the fourth resistor is connected to one end of the fourth capacitor and one end of the second potentiometer, the other end of the fourth capacitor is grounded, the other end of the second potentiometer is grounded, the sliding end of the second potentiometer is connected to one end of the fifth resistor, the other end of the fifth resistor is connected to the cathode of the third diode, and the anode of the third diode is connected to the first input end of the isolation feedback unit.

[0020] As a further solution of the present invention: the isolation feedback unit includes a third optocoupler, a sixth resistor, a fourth diode, and a fifth diode. The first end of the third optocoupler is connected to the output end of the voltage divider detection unit, the second end of the third optocoupler is grounded, the fourth end of the third optocoupler is connected to the anode of the fifth diode, the cathode of the fifth diode is grounded, the third end of the third optocoupler is connected to one end of the sixth resistor and the anode of the fourth diode, the other end of the sixth resistor is connected to the working voltage, and the cathode of the fourth diode is connected to the second input end of the switch control module.

[0021] As a further solution of the present invention: the undervoltage detection module includes:

[0022] The voltage amplification detection unit is used to detect whether the voltage of the NOR Flash chip is undervoltage, and provide a driving signal to the isolation feedback unit when undervoltage occurs;

[0023] An isolation control unit is used to stop outputting a voltage signal supplied to a switch control module when in operation;

[0024] The input end of the voltage amplification detection unit is connected to the output end of the power supply module and the second input end of the isolation control unit, the output end of the voltage amplification detection unit is connected to the first input end of the isolation control unit, and the output end of the isolation control unit is connected to the third input end of the switch control module.

[0025] As a further solution of the present invention: the voltage amplification detection unit includes a seventh resistor, an eighth resistor, a fourth transistor, and a fourth amplifier, one end of the seventh resistor is connected to the working voltage, the other end of the seventh resistor is connected to the collector of the fourth transistor, the base of the fourth transistor is connected to one end of the eighth resistor and the NOR Flash chip voltage, the other end of the eighth resistor is grounded, the emitter of the fourth transistor is connected to the inverting end of the fourth amplifier, the non-inverting end of the fourth amplifier is connected to the reference voltage, and the output end of the fourth amplifier is connected to the first input end of the isolation control unit.

[0026] As a further solution of the present invention: the isolation control unit includes a fifth optocoupler, a ninth resistor, a sixth diode, and a seventh diode. The first end of the fifth optocoupler is connected to the output end of the voltage amplification detection unit, the second end of the fifth optocoupler is grounded, the third end of the fifth optocoupler is connected to the anode of the seventh diode, the cathode of the seventh diode is grounded, the fourth end of the fifth optocoupler is connected to one end of the ninth resistor and the anode of the sixth diode, the other end of the ninth resistor is connected to the working voltage, and the cathode of the sixth diode is connected to the third input end of the switch control module.

[0027] As a further solution of the present invention: the switch control module includes a first MOS tube, a second MOS tube, a third MOS tube, and a third resistor. The S pole of the first MOS tube is connected to the processor signal data interface, the G pole of the second MOS tube is connected to the output end of the temperature detection module, the D pole of the first MOS tube is connected to the D pole of the second MOS tube, the G pole of the second MOS tube is connected to the output end of the overvoltage detection module, the S pole of the second MOS tube is connected to one end of the third resistor, the other end of the third resistor is connected to the D pole of the third MOS tube, the G pole of the third MOS tube is connected to the output end of the undervoltage detection module, and the S pole of the third MOS tube is connected to the NOR Flash chip data signal interface.

[0028] Compared with the prior art, the beneficial effect of the present invention is that the present invention selectively controls whether to disconnect the loop between the processor signal data interface and the NOR Flash chip data signal interface by detecting the temperature, voltage and other information of the NOR Flash chip, thereby avoiding the situation where the NOR Flash chip sends erroneous instructions in an unstable state, causing abnormal communication transmission information. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The figure is a schematic diagram of a NOR Flash chip voltage abnormality protection circuit.

[0030] Figure 2 This is the circuit diagram of the power supply module.

[0031] Figure 3 This is the circuit diagram of the temperature detection module.

[0032] Figure 4 This is the circuit diagram of the overvoltage detection module.

[0033] Figure 5 This is the circuit diagram of the undervoltage detection module.

[0034] Figure 6 This is the circuit diagram of the switch control module. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] See also Figure 1 , a NOR Flash chip voltage abnormality protection circuit, comprising:

[0037] A power supply module is used to supply a working voltage VCC to the temperature detection module, the overvoltage detection module, and the undervoltage detection module;

[0038] The temperature detection module is used to detect whether the temperature of the NOR Flash chip is abnormal. If it is abnormal, the circuit where the switch control module is located is disconnected;

[0039] Overvoltage detection module, used to detect whether the voltage of NOR Flash chip is overvoltage, and disconnect the circuit where the switch control module is located when overvoltage occurs;

[0040] An undervoltage detection module is used to detect whether the voltage of the NOR Flash chip is undervoltage, and disconnect the circuit where the switch control module is located when undervoltage occurs;

[0041] The switch control module is used to establish the communication between the processor data signal and the NOR Flash chip data signal when the loop is turned on;

[0042] The output end of the power supply module is connected to the input end of the temperature detection module, the input end of the overvoltage detection module, and the input end of the undervoltage detection module. The output end of the temperature detection module is connected to the first input end of the switch control module. The output end of the overvoltage detection module is connected to the second input end of the switch control module. The output end of the undervoltage detection module is connected to the third input end of the switch control module.

[0043] In this example: See Figure 2 The power supply module includes a first resistor R1, a first capacitor C1, a second capacitor C2, and a voltage regulator U1. A 12V voltage is introduced into one end of the first resistor R1, and the other end of the first resistor R1 is connected to one end of the first capacitor C1 and the input end of the voltage regulator U1. The other end of the first capacitor C1 is grounded, and the ground end of the voltage regulator U1 is grounded. The output end of the voltage regulator U1 is connected to one end of the second capacitor C2, the input end of the temperature detection module, the input end of the overvoltage detection module, and the input end of the undervoltage detection module, and the other end of the second capacitor C2 is grounded.

[0044] After the 12V voltage is input, the stabilizer U1 outputs a stable voltage, which is used as the working voltage VCC of the temperature detection module, overvoltage detection module, and undervoltage detection module.

[0045] In this example: See Figure 3 The temperature detection module includes a temperature sensor U2, a second resistor R2, a first potentiometer RP1, a third capacitor C3, a first diode D1, and a second diode D2. The power supply end of the temperature sensor U2 introduces a working voltage VCC, the ground end of the temperature sensor U2 is grounded, the output end of the temperature sensor U2 is connected to one end of the second resistor R2, the other end of the second resistor R2 is connected to one end of the first potentiometer RP1, the other end of the first potentiometer RP1 is connected to one end of the third capacitor C3 and the cathode of the first diode D1, the other end of the third capacitor C3 is grounded, the anode of the first diode D1 is connected to the anode of the second diode D2, and the cathode of the second diode D2 is connected to the first input end of the switch control module.

[0046] The temperature sensor U2 detects the NOR Flash chip information. When the temperature of the NOR Flash chip exceeds the threshold, the temperature sensor U2 outputs a voltage that is sufficient to turn on the first diode D1 (voltage-stabilizing diode) through the second resistor R2 and the first potentiometer RP1, providing a high level for the first MOS tube V1, disconnecting the first MOS tube V1, and disconnecting the processor data signal and the NOR Flash chip data signal communication.

[0047] In this example: See Figure 4 , the overvoltage detection module includes:

[0048] The voltage division detection unit is used to detect whether the voltage of the NOR Flash chip is over-voltage, and provide a driving signal to the isolation feedback unit when over-voltage occurs;

[0049] The isolation feedback unit is used to stop outputting the voltage signal supplied to the switch control module when working;

[0050] The output end of the voltage division detection unit is connected to the first input end of the isolation feedback unit, the second input end of the isolation feedback unit is connected to the output end of the power supply module, and the output end of the isolation feedback unit is connected to the second input end of the switch control module.

[0051] In this example: See Figure 4 The voltage division detection unit includes a fourth resistor R4, a fourth capacitor C4, a second potentiometer RP2, a fifth resistor R5, and a third diode D3. One end of the fourth resistor R4 introduces the NOR Flash chip voltage, the other end of the fourth resistor R4 is connected to one end of the fourth capacitor C4 and one end of the second potentiometer RP2, the other end of the fourth capacitor C4 is grounded, the other end of the second potentiometer RP2 is grounded, the sliding end of the second potentiometer RP2 is connected to one end of the fifth resistor R5, the other end of the fifth resistor R5 is connected to the cathode of the third diode D3, and the anode of the third diode D3 is connected to the first input end of the isolation feedback unit.

[0052] The NOR Flash chip voltage VIN is input, and after being divided by the fourth resistor R4 and the second potentiometer RP2, it is output to the third diode D3 through the fifth resistor R5. When the NOR Flash chip voltage VIN is not over-voltage, the third diode D3 (voltage regulator diode) is not turned on. When the NOR Flash chip voltage VIN is over-voltage, the third diode D3 (voltage regulator diode) is turned on.

[0053] In this example: See Figure 4 The isolated feedback unit includes a third optocoupler U3, a sixth resistor R6, a fourth diode D4, and a fifth diode D5. The first end of the third optocoupler U3 is connected to the output end of the voltage divider detection unit, the second end of the third optocoupler U3 is grounded, the fourth end of the third optocoupler U3 is connected to the anode of the fifth diode D5, the cathode of the fifth diode D5 is grounded, the third end of the third optocoupler U3 is connected to one end of the sixth resistor R6 and the anode of the fourth diode D4, the other end of the sixth resistor R6 is connected to the working voltage VCC, and the cathode of the fourth diode D4 is connected to the second input end of the switch control module.

[0054] After the third diode D3 is turned on, the voltage at the first end of the third optical coupler U3 is input, the internal light-emitting diode of the third optical coupler U3 emits light, and the internal photosensitive transistor of the third optical coupler U3 is turned on, so that the high level at the fourth diode D4 is converted to a low level, and the second MOS tube V2 is converted from on to off, and the processor data signal and the NOR Flash chip data signal communication are disconnected. The fifth diode D5 acts as a light-emitting diode to indicate the on state of the second MOS tube V2.

[0055] In this example: See Figure 5 , the undervoltage detection module includes:

[0056] The voltage amplification detection unit is used to detect whether the voltage of the NOR Flash chip is undervoltage, and provide a driving signal to the isolation feedback unit when undervoltage occurs;

[0057] An isolation control unit is used to stop outputting a voltage signal supplied to a switch control module when in operation;

[0058] The input end of the voltage amplification detection unit is connected to the output end of the power supply module and the second input end of the isolation control unit, the output end of the voltage amplification detection unit is connected to the first input end of the isolation control unit, and the output end of the isolation control unit is connected to the third input end of the switch control module.

[0059] In this example: See Figure 5The voltage amplification detection unit includes a seventh resistor R7, an eighth resistor R8, a fourth transistor V4, and a fourth amplifier U4. One end of the seventh resistor R7 is connected to the working voltage VCC, the other end of the seventh resistor R7 is connected to the collector of the fourth transistor V4, the base of the fourth transistor V4 is connected to one end of the eighth resistor R8 and the NOR Flash chip voltage, the other end of the eighth resistor R8 is grounded, the emitter of the fourth transistor V4 is connected to the inverting end of the fourth amplifier U4, the non-inverting end of the fourth amplifier U4 is connected to the reference voltage VREF, and the output end of the fourth amplifier U4 is connected to the first input end of the isolation control unit.

[0060] After the NOR Flash chip voltage VIN is input, it is amplified by the fourth transistor V4 and output to the inverting terminal of the fourth amplifier U4. When the NOR Flash chip voltage VIN is not under-voltage, the inverting terminal voltage of the fourth amplifier U4 is higher than the in-phase terminal voltage, and the fourth amplifier U4 outputs a low level. When the NOR Flash chip voltage VIN is under-voltage, the inverting terminal voltage of the fourth amplifier U4 is lower than the in-phase terminal voltage, and the fourth amplifier U4 outputs a high level, triggering the fifth optocoupler U5 to turn on.

[0061] In this example: See Figure 5 The isolation control unit includes a fifth optocoupler U5, a ninth resistor R9, a sixth diode D6, and a seventh diode D7. The first end of the fifth optocoupler U5 is connected to the output end of the voltage amplification detection unit, the second end of the fifth optocoupler U5 is grounded, the third end of the fifth optocoupler U5 is connected to the anode of the seventh diode D7, the cathode of the seventh diode D7 is grounded, the fourth end of the fifth optocoupler U5 is connected to one end of the ninth resistor R9 and the anode of the sixth diode D6, the other end of the ninth resistor R9 is connected to the working voltage VCC, and the cathode of the sixth diode D6 is connected to the third input end of the switch control module.

[0062] After the fifth optical coupler U5 is turned on, the internal light-emitting diode triggers the internal phototransistor to turn on. After the phototransistor is turned on, the fourth end and the third end of the fifth optical coupler U5 are connected, so that the sixth diode D6 becomes low level, so that the turned-on third MOS tube V3 becomes cut off, and the processor data signal and the NOR Flash chip data signal communication are disconnected. The seventh diode D7 acts as a light-emitting diode to indicate the conduction state of the third MOS tube V3.

[0063] In this example: See Figure 6The switch control module includes a first MOS tube V1, a second MOS tube V2, a third MOS tube V3, and a third resistor R3. The S pole of the first MOS tube V1 is connected to the processor signal data interface, the G pole of the second MOS tube V2 is connected to the output end of the temperature detection module, the D pole of the first MOS tube V1 is connected to the D pole of the second MOS tube V2, the G pole of the second MOS tube V2 is connected to the output end of the overvoltage detection module, the S pole of the second MOS tube V2 is connected to one end of the third resistor R3, the other end of the third resistor R3 is connected to the D pole of the third MOS tube V3, the G pole of the third MOS tube V3 is connected to the output end of the undervoltage detection module, and the S pole of the third MOS tube V3 is connected to the NOR Flash chip data signal interface.

[0064] The data bit width of the NOR Flash chip is 8 bits, 16 bits, etc. Here, the data bit width of the NOR Flash chip is 16 bits as an example. The data signals D0-D15 of the ARM processor are connected one-to-one with the data signals D0-D15 of the 16-bit NOR Flash chip to realize the transmission of 16-bit data. When the temperature of the NOR Flash chip is normal and there is no undervoltage or overvoltage, the first MOS tube V1, the second MOS tube V2, and the third MOS tube V3 are all turned on, and the ARM processor data signal and the NOR Flash chip data signal are communicated and connected for data transmission.

[0065] The working principle of the present invention is as follows: a power supply module is used to supply a working voltage VCC to a temperature detection module, an overvoltage detection module and an undervoltage detection module; the temperature detection module is used to detect whether the temperature of a NOR Flash chip is abnormal, and disconnects the circuit where a switch control module is located when the temperature is abnormal; the overvoltage detection module is used to detect whether the voltage of a NOR Flash chip is overvoltage, and disconnects the circuit where a switch control module is located when the voltage is overvoltage; the undervoltage detection module is used to detect whether the voltage of a NOR Flash chip is undervoltage, and disconnects the circuit where a switch control module is located when the voltage is undervoltage; and the switch control module is used to establish communication between a processor data signal and a NOR Flash chip data signal when the circuit is turned on.

[0066] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered as exemplary and non-restrictive in all respects.

[0067] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A NOR Flash chip voltage abnormality protection circuit, characterized in that: The NOR Flash chip voltage abnormality protection circuit includes: A power supply module, used to supply working voltage to the temperature detection module, the overvoltage detection module, and the undervoltage detection module; The temperature detection module is used to detect whether the temperature of the NOR Flash chip is abnormal. If it is abnormal, the circuit where the switch control module is located is disconnected; Overvoltage detection module, used to detect whether the voltage of NOR Flash chip is overvoltage, and disconnect the circuit where the switch control module is located when overvoltage occurs; An undervoltage detection module is used to detect whether the voltage of the NOR Flash chip is undervoltage, and disconnect the circuit where the switch control module is located when undervoltage occurs; The switch control module is used to establish the communication between the processor data signal and the NOR Flash chip data signal when the loop is turned on; The output end of the power supply module is connected to the input end of the temperature detection module, the input end of the overvoltage detection module, and the input end of the undervoltage detection module. The output end of the temperature detection module is connected to the first input end of the switch control module. The output end of the overvoltage detection module is connected to the second input end of the switch control module. The output end of the undervoltage detection module is connected to the third input end of the switch control module.

2. The NOR Flash chip voltage abnormality protection circuit according to claim 1, characterized in that: The power supply module includes a first resistor, a first capacitor, a second capacitor, and a voltage regulator. A 12V voltage is introduced into one end of the first resistor, the other end of the first resistor is connected to one end of the first capacitor and the input end of the voltage regulator, the other end of the first capacitor is grounded, the ground end of the voltage regulator is grounded, the output end of the voltage regulator is connected to one end of the second capacitor, the input end of the temperature detection module, the input end of the overvoltage detection module, and the input end of the undervoltage detection module, and the other end of the second capacitor is grounded.

3. The NOR Flash chip voltage abnormality protection circuit according to claim 1, characterized in that: The temperature detection module includes a temperature sensor, a second resistor, a first potentiometer, a third capacitor, a first diode, and a second diode. The working voltage is introduced into the power supply end of the temperature sensor, the ground end of the temperature sensor is grounded, the output end of the temperature sensor is connected to one end of the second resistor, the other end of the second resistor is connected to one end of the first potentiometer, the other end of the first potentiometer is connected to one end of the third capacitor and the cathode of the first diode, the other end of the third capacitor is grounded, the anode of the first diode is connected to the anode of the second diode, and the cathode of the second diode is connected to the first input end of the switch control module.

4. The NOR Flash chip voltage abnormality protection circuit according to claim 1, characterized in that: The overvoltage detection module includes: The voltage division detection unit is used to detect whether the voltage of the NOR Flash chip is over-voltage, and provide a driving signal to the isolation feedback unit when it is over-voltage; The isolation feedback unit is used to stop outputting the voltage signal supplied to the switch control module when working; The output end of the voltage division detection unit is connected to the first input end of the isolation feedback unit, the second input end of the isolation feedback unit is connected to the output end of the power supply module, and the output end of the isolation feedback unit is connected to the second input end of the switch control module.

5. The NOR Flash chip voltage abnormality protection circuit according to claim 4, characterized in that: The voltage divider detection unit includes a fourth resistor, a fourth capacitor, a second potentiometer, a fifth resistor, and a third diode. One end of the fourth resistor introduces the NOR Flash chip voltage, the other end of the fourth resistor is connected to one end of the fourth capacitor and one end of the second potentiometer, the other end of the fourth capacitor is grounded, the other end of the second potentiometer is grounded, the sliding end of the second potentiometer is connected to one end of the fifth resistor, the other end of the fifth resistor is connected to the cathode of the third diode, and the anode of the third diode is connected to the first input end of the isolation feedback unit.

6. The NOR Flash chip voltage abnormality protection circuit according to claim 4, characterized in that: The isolation feedback unit includes a third optocoupler, a sixth resistor, a fourth diode, and a fifth diode. The first end of the third optocoupler is connected to the output end of the voltage divider detection unit, the second end of the third optocoupler is grounded, the fourth end of the third optocoupler is connected to the anode of the fifth diode, the cathode of the fifth diode is grounded, the third end of the third optocoupler is connected to one end of the sixth resistor and the anode of the fourth diode, the other end of the sixth resistor is connected to the working voltage, and the cathode of the fourth diode is connected to the second input end of the switch control module.

7. The NOR Flash chip voltage abnormality protection circuit according to claim 1, characterized in that: The undervoltage detection module includes: The voltage amplification detection unit is used to detect whether the voltage of the NOR Flash chip is undervoltage, and provide a driving signal to the isolation feedback unit when undervoltage occurs; An isolation control unit is used to stop outputting a voltage signal supplied to a switch control module when in operation; The input end of the voltage amplification detection unit is connected to the output end of the power supply module and the second input end of the isolation control unit, the output end of the voltage amplification detection unit is connected to the first input end of the isolation control unit, and the output end of the isolation control unit is connected to the third input end of the switch control module.

8. The NOR Flash chip voltage abnormality protection circuit according to claim 7, characterized in that: The voltage amplification detection unit includes a seventh resistor, an eighth resistor, a fourth transistor, and a fourth amplifier. One end of the seventh resistor is connected to the working voltage, the other end of the seventh resistor is connected to the collector of the fourth transistor, the base of the fourth transistor is connected to one end of the eighth resistor and the NORFlash chip voltage, the other end of the eighth resistor is grounded, the emitter of the fourth transistor is connected to the inverting end of the fourth amplifier, the non-inverting end of the fourth amplifier is connected to the reference voltage, and the output end of the fourth amplifier is connected to the first input end of the isolation control unit.

9. The NOR Flash chip voltage abnormality protection circuit according to claim 7, characterized in that: The isolation control unit includes a fifth optocoupler, a ninth resistor, a sixth diode, and a seventh diode. The first end of the fifth optocoupler is connected to the output end of the voltage amplification detection unit, the second end of the fifth optocoupler is grounded, the third end of the fifth optocoupler is connected to the anode of the seventh diode, the cathode of the seventh diode is grounded, the fourth end of the fifth optocoupler is connected to one end of the ninth resistor and the anode of the sixth diode, the other end of the ninth resistor is connected to the working voltage, and the cathode of the sixth diode is connected to the third input end of the switch control module.

10. The NOR Flash chip voltage abnormality protection circuit according to any one of claims 1 to 9, characterized in that: The switch control module includes a first MOS tube, a second MOS tube, a third MOS tube, and a third resistor. The S pole of the first MOS tube is connected to the processor signal data interface, the G pole of the second MOS tube is connected to the output end of the temperature detection module, the D pole of the first MOS tube is connected to the D pole of the second MOS tube, the G pole of the second MOS tube is connected to the output end of the overvoltage detection module, the S pole of the second MOS tube is connected to one end of the third resistor, the other end of the third resistor is connected to the D pole of the third MOS tube, the G pole of the third MOS tube is connected to the output end of the undervoltage detection module, and the S pole of the third MOS tube is connected to the NOR Flash chip data signal interface.

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