Chip low-temperature self-heating circuit based on adaptive temperature compensation

Abstract

A chip low-temperature self-heating circuit based on adaptive temperature compensation comprises a temperature acquisition circuit, a comparator circuit, a micro-control unit, a power driving circuit and a heating resistor network, and adopts a segmented temperature compensation technology and a local heating mode. The temperature rise speed is automatically adjusted, so that a key chip in the alternating current charging pile is rapidly and stably heated in a low-temperature environment, and the reliability of the heating circuit is further improved through the dual-heating control design; compared with a conventional heating box or a heating pad and the like for heating the whole circuit board, the chip low-temperature self-heating circuit based on self-adaptive temperature compensation can reduce temperature fluctuation in a temperature control process and reduce electric energy waste in a heating process while ensuring stable work of the alternating current charging pile in a low-temperature environment.

Description

Technical Field

[0001] The present invention relates to the technical field of low-temperature resistance of the main control board of charging piles, and specifically to a chip low-temperature self-heating circuit based on adaptive temperature compensation. Background Technique

[0002] With the popularization of new energy vehicles, charging piles, as key infrastructure, have been widely used. In the cold north, the environment can reach as low as -40°C, and the performance of the chips on the main control board of charging piles will significantly decline. Charging piles often face problems such as difficult startup, unstable operation, and even damage. Existing solutions such as heating boxes or heating pads mostly rely on external heaters or self-heating circuits with fixed power to heat the entire circuit board, resulting in problems such as uncontrollable heating rate and excessive heating coverage, leading to large temperature fluctuations during the temperature control process and waste of electric energy. Summary of the Invention

[0003] The purpose of the present invention is to provide a chip low-temperature self-heating circuit based on adaptive temperature compensation to solve the problems raised in the above background technique. Through segmented temperature compensation technology, dual heating control design, and local heating scheme, the key chips on the main control board of AC charging piles can be automatically and quickly heated up in a low-temperature environment, and the heating rate can be automatically reduced when approaching the constant temperature range, so that the temperature can finally be stably maintained within the temperature range suitable for the operation of the chips. Compared with existing heating methods such as heating boxes and heating pads, it can reduce the temperature fluctuations during the temperature control process and at the same time reduce the waste of electric energy in the way of heating the entire circuit board by existing heating boxes and heating pads.

[0004] To achieve the above object, the present invention provides the following technical solution: A chip low-temperature self-heating circuit based on adaptive temperature compensation, comprising a temperature acquisition circuit 1, a comparator circuit 2, a micro-control unit 3, a power drive circuit 4, and a heating resistor network 5; the output end of the temperature acquisition circuit 1 is connected to the power drive circuit 4 through the comparator circuit 2 and the micro-control unit 3, and the power drive circuit 4 is connected to the heating resistor network 5; the temperature acquisition circuit 1 includes a thermistor R1, a capacitor C1, and a resistor R2. One end of the thermistor R1 is connected to GND, and the other end is connected to the power supply VCC through the resistor R2. The capacitor C1 is connected in parallel with the thermistor R1. The node between the thermistor R1 and the resistor R2 is connected to the input end (temp-in) of the single-chip microcomputer U2 in the micro-control unit 3 on the one hand, and to the resistor R6 in the comparator circuit 2 on the other hand; the comparator circuit 2 includes a comparator U1, resistors R6, R7, R8, R9, R10, and R11. The positive input end (pin 3) of the comparator U1 is connected to the resistor R7 on the one hand. The other end of the resistor R7 is connected to the resistors R8 and R9. The other end of the resistor R8 is connected to the power supply VCC, and the other end of the resistor R9 is connected to GND. The positive input end (pin 3) of the comparator U1 is connected to the output end (pin 1) of the comparator U1 through the resistor R11 on the other hand. The negative input end (pin 2) of the comparator U1 is connected to the node between the thermistor R1 and the resistor R2 in the temperature acquisition circuit 1 through the resistor R6. The output end (pin 1) of the comparator U1 is connected to the power supply VCC through the resistor R10 on the one hand, and to the output end (pwm-out) of the single-chip microcomputer U2 in the micro-control unit 3 and the resistor R3 in the power drive circuit 4 on the other hand; the micro-control unit 3 includes a single-chip microcomputer U2. The temperature signal input end (temp-in) of the single-chip microcomputer U2 is connected to the node between the thermistor R1 and the resistor R2 in the temperature acquisition circuit 1. The output end (pwm-out) of the single-chip microcomputer U2 is connected to the output end (pin 1) of the comparator U1 in the comparator circuit 2 and the resistor R3 in the power drive circuit 4; the power drive circuit 4 includes a PNP transistor Q1, an NPN transistor Q2, resistors R3, R4, R5, and a MOS transistor Q3. One end of the resistor R3 is connected to the output end (pwm-out) of the single-chip microcomputer U2 in the micro-control unit 3, and the other end is simultaneously connected to the bases of the transistors Q1 and Q2. The emitter of the transistor Q1 is connected to the power supply VCC1. The collector of the transistor Q1 is connected to the collector of the transistor Q2. The emitter of the transistor Q2 is connected to GND. One end of the resistor R4 is connected to the collectors of the transistors Q1 and Q2, and the other end is connected to GND through the resistor R5. The node between the resistors R4 and R5 is connected to the gate of the MOS transistor Q3. The source of the MOS transistor Q3 is connected to GND, and the drain of the MOS transistor Q3 is connected to the heating resistor network 5;The heating resistance network 5 includes 12 resistors (resistor R12 to resistor R23). Resistor R12, resistor R13, and resistor R14 are connected in series to form the first resistor series circuit. Resistor R15, resistor R16, and resistor R17 are connected in series to form the second resistor series circuit. Resistor R18, resistor R19, and resistor R20 are connected in series to form the third resistor series circuit. Resistor R21, resistor R22, and resistor R23 are connected in series to form the fourth resistor series circuit. The four resistor series circuits are connected in parallel. The nodes between resistor R12, resistor R15, resistor R18, and resistor R21 are connected to the power supply VCC1. The nodes between resistor R14, resistor R17, resistor R20, and resistor R23 are connected to the drain of MOS transistor Q3 in the power driving circuit 4.;

[0005] Further, the heating resistance network 5 is arranged around the heating target chip 6.

[0006] Further, pin 8 of the comparator U1 is connected to the power supply VCC, and pin 4 of the comparator U1 is connected to GND.

[0007] Further, the comparator U1 is a dual-channel comparator LM193.

[0008] Further, the comparator U1 is a dual-channel comparator LM393B.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows: The chip low-temperature self-heating circuit based on adaptive temperature compensation can automatically and rapidly increase the temperature of the key chip on the main control board of the AC charging pile in a low-temperature environment, and automatically reduce the heating rate when approaching the constant temperature range, so that the temperature can finally be stably maintained within the temperature range suitable for the chip to work. Compared with the existing heating methods such as heating boxes and heating pads, it can reduce the temperature fluctuation during the temperature control process. At the same time, the local heating scheme can reduce the power waste of the existing heating boxes and heating pads for the overall heating of the circuit board. Description of the Drawings

[0010] Figure 1 It is the structural block diagram of the present invention; Figure 2 It is the circuit schematic diagram of the present invention; Figure 3 It is the schematic diagram of the layout of the local heating resistance network.

[0011] In the figure: 1. Temperature acquisition circuit; 2. Comparator circuit; 3. Micro control unit; 4. Power driving circuit; 5. Heating resistance network; 6. Heating target chip. Detailed Embodiments

[0012] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a 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 those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0013] Please refer to Figure 1 , Figure 2 and Figure 3, the present invention provides a technical solution: a chip low-temperature self-heating circuit based on adaptive temperature compensation, including a temperature acquisition circuit 1, a comparator circuit 2, a micro-control unit 3, a power drive circuit 4 and a heating resistor network 5; the output end of the temperature acquisition circuit 1 is connected to the power drive circuit 4 through the comparator circuit 2 and the micro-control unit 3, and the power drive circuit 4 is connected to the heating resistor network 5; the temperature acquisition circuit 1 includes a thermistor R1, a capacitor C1 and a resistor R2. One end of the thermistor R1 is connected to GND, and the other end is connected to the power supply VCC through the resistor R2. The capacitor C1 is connected in parallel with the thermistor R1. The node between the thermistor R1 and the resistor R2 is connected to the input end (temp-in) of the single-chip microcomputer U2 in the micro-control unit 3 on the one hand, and to the resistor R6 in the comparator circuit 2 on the other hand. The comparator circuit 2 includes a comparator U1, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10 and a resistor R11. The positive input end (pin 3) of the comparator U1 is connected to the resistor R7 on the one hand. The other end of the resistor R7 is connected to the resistor R8 and the resistor R9. The other end of the resistor R8 is connected to the power supply VCC, and the other end of the resistor R9 is connected to GND. The positive input end (pin 3) of the comparator U1 is connected to the output end (pin 1) of the comparator U1 through the resistor R11 on the other hand. The negative input end (pin 2) of the comparator U1 is connected to the node between the thermistor R1 and the resistor R2 in the temperature acquisition circuit 1 through the resistor R6. The output end (pin 1) of the comparator U1 is connected to the power supply VCC through the resistor R10 on the one hand, and to the output end (pwm-out) of the single-chip microcomputer U2 in the micro-control unit 3 and the resistor R3 in the power drive circuit 4 on the other hand. The micro-control unit 3 includes a single-chip microcomputer U2. The temperature signal input end (temp-in) of the single-chip microcomputer U2 is connected to the node between the thermistor R1 and the resistor R2 in the temperature acquisition circuit 1. The output end (pwm-out) of the single-chip microcomputer U2 is connected to the output end (pin 1) of the comparator U1 in the comparator circuit 2 and the resistor R3 in the power drive circuit 4. The power drive circuit 4 includes a PNP triode Q1, an NPN triode Q2, a resistor R3, a resistor R4, a resistor R5 and a MOS tube Q3. One end of the resistor R3 is connected to the output end (pwm-out) of the single-chip microcomputer U2 in the micro-control unit 3, and the other end is simultaneously connected to the base of the triode Q1 and the base of the triode Q2. The emitter of the triode Q1 is connected to the power supply VCC1. The collector of the triode Q1 is connected to the collector of the triode Q2. The emitter of the triode Q2 is connected to GND. One end of the resistor R4 is connected to the collector of the triode Q1 and the collector of the triode Q2, and the other end is connected to GND through the resistor R5. The node between the resistor R4 and the resistor R5 is connected to the gate of the MOS tube Q3. The source of the MOS tube Q3 is connected to GND, and the drain of the MOS tube Q3 is connected to the heating resistor network 5.The heating resistance network 5 includes 12 resistors (resistor R12 to resistor R23). Resistor R12, resistor R13, and resistor R14 are connected in series to form the first resistor series circuit. Resistor R15, resistor R16, and resistor R17 are connected in series to form the second resistor series circuit. Resistor R18, resistor R19, and resistor R20 are connected in series to form the third resistor series circuit. Resistor R21, resistor R22, and resistor R23 are connected in series to form the fourth resistor series circuit. The four resistor series circuits are connected in parallel. The nodes between resistor R12, resistor R15, resistor R18, and resistor R21 are connected to the power supply VCC1. The nodes between resistor R14, resistor R17, resistor R20, and resistor R23 are connected to the drain of MOS transistor Q3 in the power drive circuit 4. Further, the heating resistance network 5 is arranged around the heating target chip to achieve local heating.

[0014] Further, the heating resistance network 5 is arranged around the heating target chip 6.

[0015] Further, pin 8 of the comparator U1 is connected to the power supply VCC, and pin 4 of the comparator U1 is connected to GND.

[0016] Further, the comparator U1 is a dual-channel comparator LM193.

[0017] Further, the comparator U1 is a dual-channel comparator LM393B.

[0018] Working principle: The temperature acquisition circuit 1 simultaneously sends the acquired temperature signal to the comparator circuit 2 and the micro-control unit 3. The micro-control unit 3 performs arithmetic processing on the temperature signal and outputs a heating signal to control the power drive circuit 4 to turn on the heating resistance network 5 to achieve local heating and constant temperature control of the target chip area on the circuit board. The function of the comparator circuit 2 is to prevent the single-chip microcomputer U2 in the micro-control unit 3 from working unstably or being in a fault state when the device is initially powered on in a too-low temperature environment. At this time, it is necessary to rely on the comparator circuit 2 to start heating to achieve rapid temperature rise. When the temperature rises to a temperature value suitable for the chip to work stably, the micro-control unit 3 automatically adjusts the heating rate to achieve heating and constant temperature control. The comparator circuit 2 and the micro-control unit 3 jointly participate in realizing dual heating control.

[0019] During the operation of the circuit, different control methods are adopted in different temperature ranges to ensure the rapidity and stability of the heating process. When the temperature is too low, the comparator circuit 2 and the micro-control unit 3 jointly participate in the heating control to achieve rapid heating. When the temperature rises to a certain range, the micro-control unit 3 participates in the heating control to automatically adjust the heating and rising speed. The specific ranges are divided into the rapid heating section jointly controlled by the comparator circuit 2 and the micro-control unit 3, the rising section alternately controlled by the comparator circuit 2 and the micro-control unit 3, the speed-adjusting heating section controlled by the micro-control unit 3, and the constant temperature section controlled by the micro-control unit 3. Each temperature range section can be set and modified by changing the parameters of the resistance element and the single-chip microcomputer program.

[0020] In the temperature acquisition circuit 1, the resistance value of the resistor R2 is 50 KΩ, and the thermistor R1 is a negative temperature coefficient thermistor with a resistance value of 10 KΩ (at 25 °C). During the heating process, according to the temperature parameters of the target chip, the temperature values of the temperature range separation points are set as: -20 °C, -16 °C, -10 °C, 0 °C (each separation point can be adjusted according to actual needs). The resistance values of the thermistor R1 corresponding to each temperature value are: 70.58 KΩ, 58.41 KΩ, 44.12 KΩ, 28.02 KΩ respectively. The voltage value of the power supply VCC is DC 3.3 V. According to circuit analysis and calculation, at -20 °C, -16 °C, -10 °C, 0 °C, the temperature signal values output by the temperature acquisition circuit 1 are: 1.93 V, 1.78 V, 1.55 V, 1.19 V respectively. The resistor R2 and the capacitor C1 form an RC filter circuit to filter out the noise in the temperature signal.

[0021] Comparator circuit 2 is to prevent the single-chip microcomputer U2 in the microcontroller unit 3 from working unstably or being in a fault state when the device is powered on for the first time in a too low temperature environment, to achieve automatic startup of rapid heating when the temperature is lower than -20°C. At the same time, to suppress the noise interference caused at the temperature critical point, improve the stability of the circuit, and reduce the temperature fluctuation, a hysteresis circuit is added to achieve constant temperature control in the range of -20°C to -16°C. The resistance value of resistor R6 is 1KΩ, the resistance value of resistor R7 is 1KΩ, the resistance value of resistor R8 is 7.6KΩ, the resistance value of resistor R9 is 10KΩ, the resistance value of resistor R10 is 20KΩ, the resistance value of resistor R11 is 100KΩ, and the voltage value of power supply VCC is DC3.3V. According to the above resistance values, it can be calculated that no matter how the output terminal (pin 1) of comparator U1 changes, the voltage at the positive input terminal (pin 3) of comparator U1 is always less than or equal to 1.93V. When the temperature is lower than -20°C, the voltage output by the temperature acquisition circuit 1 to the negative input terminal (pin 2) of comparator U1 is greater than 1.93V, and the output terminal (pin 1) of comparator U1 outputs a low level to make the MOS tube Q3 in the power drive circuit 4 conduct, and the heating resistor network 5 works. At this time, the voltage at the positive input terminal (pin 3) of comparator U1 is 1.78V. As the temperature gradually rises, when the temperature is higher than -16°C, the voltage output by the temperature acquisition circuit 1 to the negative input terminal (pin 2) of comparator U1 is less than 1.78V, and the output terminal (pin 1) of comparator U1 outputs a high level, and the heating resistor network 5 is controlled to stop heating through the power drive circuit 4. At this time, the voltage at the positive input terminal (pin 3) of comparator U1 becomes 1.93V. When the temperature drops below -20°C again, the above working process is repeated; in the circuit, the output states of the output terminal (pin 1) of comparator U1 and the output terminal (pwm-out) of the single-chip microcomputer U2 in the microcontroller unit 3 are both high levels when the heating stops, and the internal circuits are both open-drain outputs. Therefore, the output signals of comparator circuit 2 and the microcontroller unit 3 do not affect each other.

[0022] When the single-chip microcomputer U2 in the microcontroller unit 3 detects that the temperature is lower than -20°C, it outputs a heating signal simultaneously with the comparator circuit 2. The single-chip microcomputer U2 outputs a pulse width modulation signal to drive the MOS tube Q3 through a drive circuit mainly composed of triode Q1 and triode Q2, so that the heating resistor network 5 composed of resistors R12 to R23 works. When the temperature is lower than -20°C, the single-chip microcomputer U2 automatically adjusts the duty cycle of the pulse width modulation signal to make the conduction amount of the MOS tube Q3 reach the maximum value, so that the heating resistor network 5 heats up rapidly. When the temperature acquisition circuit 1 detects that the temperature around the target chip rises to between -20°C and -10°C, the single-chip microcomputer U2 adjusts the duty cycle of the pulse width modulation signal to appropriately reduce the conduction amount of the MOS tube Q3 to prevent the temperature from overshooting due to too fast heating speed. When the ambient temperature approaches 0°C, the single-chip microcomputer U2 adjusts the duty cycle of the pulse width modulation signal to gradually reduce the conduction amount of the MOS tube Q3, and finally maintains a dynamic balance near the 0°C temperature to achieve temperature constancy.

[0023] According to the ambient temperature, there are specifically the following five working states: When the temperature is lower than -20°C, the resistance value of the thermistor R1 is greater than or equal to 70.58 KΩ. The voltage at the negative input terminal (pin 2) of the comparator U1 is higher than 1.93 V, and the voltage at the positive input terminal (pin 3) of the comparator U1 is 1.93 V, lower than the voltage at the negative input terminal (pin 2) of the comparator U1. The output terminal (pin 1) of the comparator U1 outputs a low level. At this time, regardless of whether the state of the output terminal (pwm-out) of the single-chip microcomputer U2 is at a high level (fault state) or a low level (normal state), the signal transmitted to the power drive circuit 4 is a low level. The low level makes the MOS transistor Q3 in the power drive circuit 4 conduct, realizing rapid heating. This stage is the stage where the comparator circuit 2 and the micro-control unit 3 jointly control the rapid heating section.

[0024] When the temperature is between -20°C and -16°C, the resistance value of the thermistor R1 is between 70.58 KΩ and 58.41 KΩ. The voltage at the negative input terminal (pin 2) of the comparator U1 is between 1.93 V and 1.78 V. In this temperature range, the output terminal (pin 1) of the comparator U1 outputs two states: low level or high level. When the output terminal (pin 1) of the comparator U1 outputs a low level, the voltage at the positive input terminal (pin 3) of the comparator U1 is 1.78 V, and the heating is controlled by the comparator circuit 2. When the output terminal (pin 1) of the comparator U1 outputs a high level, the voltage at the positive input terminal (pin 3) of the comparator U1 is 1.93 V, and the heating is controlled by the single-chip microcomputer U2. This stage is the stage where the comparator circuit 2 and the micro-control unit 3 alternately control the heating section.

[0025] When the temperature is between -16°C and -10°C, the resistance value of the thermistor R1 is between 58.41 KΩ and 44.12 KΩ. The voltage at the negative input terminal (pin 2) of the comparator U1 is between 1.78 V and 1.55 V. The voltage at the positive input terminal (pin 3) of the comparator U1 is 1.78 V, higher than the voltage at the negative input terminal (pin 2) of the comparator U1. The output terminal (pin 1) of the comparator U1 outputs a high level. At this time, the single-chip microcomputer U2 adjusts the duty cycle of the pulse width modulation signal according to the temperature rise situation to control the heating. This stage is the stage where the micro-control unit 3 controls the speed regulation and heating section.

[0026] When the temperature is between -10°C and 0°C, the resistance value of the thermistor R1 is between 44.12 KΩ and 28.02 KΩ. The voltage at the negative input terminal (pin 2) of the comparator U1 is between 1.55 V and 1.19 V. The voltage at the positive input terminal (pin 3) of the comparator U1 is 1.78 V, higher than the voltage at the negative input terminal (pin 2) of the comparator U1. The output terminal (pin 1) of the comparator U1 outputs a high level. At this time, the single-chip microcomputer U2 adjusts the duty cycle of the pulse width modulation signal according to the temperature rise situation to control the heating, realizing slow heating.

[0027] When the temperature rises above 0°C, the resistance value of the thermistor R1 is less than 28.02 KΩ. The voltage at the negative input terminal (pin 2) of the comparator U1 is lower than 1.19 V, and the voltage at the positive input terminal (pin 3) of the comparator U1 is 1.78 V, which is higher than the voltage at the negative input terminal (pin 2) of the comparator U1. The output terminal (pin 1) of the comparator U1 outputs a high level. At the same time, after the microcontroller U2 detects that the temperature is higher than 0°C, it stops outputting the pulse width modulation signal and maintains the output of a high level. The high level turns off the MOS transistor Q3 in the power drive circuit 4, stopping the heating. This stage, like stage (4), is the constant temperature control stage controlled by the microcontrol unit 3.

[0028] Due to the implementation of the above solution, the low-temperature self-heating circuit of the chip based on adaptive temperature compensation can automatically and rapidly increase the temperature of the key chip on the main control board of the AC charging pile in a low-temperature environment, automatically reduce the heating rate when approaching the constant temperature range, and finally stably maintain within the temperature range suitable for the chip to work. Compared with the existing heating methods such as heating boxes and heating pads, it can reduce the temperature fluctuation during the temperature control process. At the same time, the local heating solution can reduce the power waste of the overall heating method of the existing heating boxes and heating pads on the circuit board.

[0029] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A chip low temperature self-heating circuit based on adaptive temperature compensation, characterized in that: The invention comprises a temperature acquisition circuit (1), a comparator circuit (2), a micro control unit (3), a power drive circuit (4) and a heating resistor network (5); the output end of the temperature acquisition circuit (1) is connected to the power drive circuit (4) through the comparator circuit (2) and the micro control unit (3), and the power drive circuit (4) is connected to the heating resistor network (5); the temperature acquisition circuit (1) comprises a thermistor R1, a capacitor C1 and a resistor R2, one end of the thermistor R1 is connected to GND, and the other end is connected to a power supply VCC through the resistor R2, the capacitor C1 is connected to the thermistor R1 in parallel, and the node between the thermistor R1 and the resistor R2 is connected to the input of a single chip computer U2 in the micro control unit (3) on one hand. The comparator circuit (2) comprises a comparator U1, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10 and a resistor R11. The positive input terminal (pin 3) of the comparator U1 is connected to the resistor R7 on one hand, the other end of the resistor R7 is connected to the resistor R8 and the resistor R9, the other end of the resistor R8 is connected to the power supply VCC, and the other end of the resistor R9 is connected to GND. The positive input terminal (pin 3) of the comparator U1 is connected to the output terminal (pin 1) of the comparator U1 through the resistor R11 on the other hand, and the negative input terminal (pin 2) of the comparator U1 is connected to the node between the thermistor R1 and the resistor R2 in the temperature acquisition circuit (1) through the resistor R6. The output end (pin 1) of the comparator U1 is connected to the power supply VCC via the resistor R10 on the one hand, and is connected to the output end (pwm-out) of the single-chip microcomputer U2 in the microcontroller (3) and the resistor R3 in the power drive circuit (4) on the other hand; the microcontroller (3) comprises a single-chip microcomputer U2, the temperature signal input end (temp-in) of the single-chip microcomputer U2 is connected to the node between the thermistor R1 and the resistor R2 in the temperature acquisition circuit (1), and the output end (pwm-out) of the single-chip microcomputer U2 is connected to the output end (pin 1) of the comparator U1 in the comparator circuit (2) and the resistor R3 in the power drive circuit (4); the power drive circuit (4) comprises a PNP transistor Q1, an NPN transistor Q 2. Resistor R3, resistor R4, resistor R5 and MOS tube Q3, one end of resistor R3 is connected to the output end (pwm-out) of single chip computer U2 in micro control unit (3), and the other end is connected to the base of transistor Q1 and the base of transistor Q2 at the same time, the emitter of transistor Q1 is connected to power supply VCC1, the collector of transistor Q1 is connected to the collector of transistor Q2, the emitter of transistor Q2 is connected to GND, one end of resistor R4 is connected to the collector of transistor Q1 and the collector of transistor Q2, and the other end is connected to GND via resistor R5, the node between resistor R4 and resistor R5 is connected to the gate of MOS tube Q3, the source of MOS tube Q3 is connected to GND, and the drain of MOS tube Q3 is connected to heating resistor network (5);The heating resistor network (5) includes 12 resistors (resistors R12 to R23), wherein resistors R12, R13, and R14 are connected in series to form a first resistor series circuit, resistors R15, R16, and R17 are connected in series to form a second resistor series circuit, resistors R18, R19, and R20 are connected in series to form a third resistor series circuit, resistors R21, R22, and R23 are connected in series to form a fourth resistor series circuit, and the four resistor series circuits are connected in parallel, the node between resistors R12, R15, R18, and R21 is connected to a power supply VCC1, and the node between resistors R14, R17, R20, and R23 is connected to the drain of the MOS tube Q3 in the power drive circuit (4). ; 2. The chip low temperature self-heating circuit based on adaptive temperature compensation according to claim 1 is characterized in that: The heating resistor network (5) is arranged around the heating target chip (6).

3. The chip low temperature self-heating circuit based on adaptive temperature compensation according to claim 1, characterized in that: Pin 8 of the comparator U1 is connected to the power supply VCC, and pin 4 of the comparator U1 is connected to GND.

4. The chip low temperature self-heating circuit based on adaptive temperature compensation according to claim 1, characterized in that: The comparator U1 is a dual comparator LM193.

5. The chip low temperature self-heating circuit based on adaptive temperature compensation according to claim 1, characterized in that: The comparator U1 is a dual-channel comparator LM393B.

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