Wide supply voltage range high precision reference circuit

Abstract

This invention relates to integrated circuit technology and includes a wide power supply voltage range high-precision reference circuit. The circuit comprises a reference voltage generation circuit, a high-temperature segmented compensation circuit, a load drive circuit, and a final-stage amplifier output circuit. The reference voltage generation circuit outputs a positive-temperature characteristic control signal to the load drive circuit and a positive-temperature extraction control signal to the high-temperature segmented compensation circuit. The output of the load drive circuit is connected to the final-stage amplifier output circuit, and the extraction current input of the high-temperature segmented compensation circuit is connected to the output of the final-stage amplifier output circuit. This invention features a wide power supply voltage range, low temperature drift, high precision, and low process dependence.

Description

Technical Field

[0001] This invention relates to integrated circuit technology. Background Technology

[0002] In signal acquisition systems, the reference circuit is a core component ensuring the accuracy of analog-to-digital signal conversion. Its role spans the entire process of signal conditioning, analog-to-digital conversion, digital-to-analog conversion, and data processing, directly impacting the system's measurement accuracy, stability, and reliability. In industrial control, automotive electronics, and other fields, sensors or signal sources often operate in high common-mode voltage environments, such as 12V / 24V battery systems and long-distance transmission lines in industrial settings. For example, industrial power supplies often experience voltage fluctuations due to line losses and load variations; a 12V power supply may drop to 9V or boost to 15V. In automobiles, battery voltage can fluctuate significantly, dropping to 6V during startup and rising to 14.5V during charging. Traditional solutions require adding linear regulators or isolation circuits to stabilize the input voltage before connecting it to the reference chip if the power supply voltage fluctuations are large or the common-mode voltage is high. This increases the number of components in the system and raises costs.

[0003] Low temperature coefficient and low power consumption reference circuit design are crucial in ADC, DAC, FLASH, and DRAM designs. Traditional reference circuits employ a bandgap structure, which is simple, has low power consumption, and is easy to implement. The most widely used first-order temperature compensation structure has a temperature coefficient of approximately 40ppm / ℃ to 60ppm / ℃. However, first-order compensation methods cannot cover the higher-order temperature terms of VBE. Temperatures exceeding 110℃ cause a surge in carrier concentration and leakage current in semiconductor devices. Furthermore, the temperature characteristics of higher-order compensation circuits are highly dependent on process technology, and the inflection point for the surge in temperature drift varies across different fabrication processes. Traditional reference circuit structures often fail to simultaneously achieve a wide power supply voltage range, low temperature drift, high accuracy, and low process dependence. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a high-temperature segmented compensation circuit that uses a resistor current branch to realize an adjustable temperature compensation point and performs curvature compensation on the reference source to obtain a high-precision reference voltage.

[0005] The technical solution adopted by the present invention to solve the aforementioned technical problem is a high-precision reference circuit with a wide power supply voltage range, characterized in that it includes a reference voltage generation circuit, a high-temperature segmented compensation circuit, a load driving circuit, and a final stage amplification output circuit.

[0006] The reference voltage generation circuit outputs a positive temperature characteristic control signal to the load drive circuit and a positive temperature extraction control signal to the high-temperature segmented compensation circuit. The output of the load drive circuit is connected to the final stage amplifier output circuit, and the extraction current input of the high-temperature segmented compensation circuit is connected to the output of the final stage amplifier output circuit. The extraction current of the high-temperature segmented compensation circuit is positively correlated with the positive temperature extraction control signal.

[0007] The reference voltage input terminal VREF of the reference voltage generation circuit is connected to the output terminal of the final stage amplifier output circuit. The two differential input terminals of the reference voltage generation circuit are connected to the voltage divider resistor string. The reference voltage input terminal is grounded through the voltage divider resistor string and transistor Q3.

[0008] The output terminal of the final stage amplifier output circuit is grounded through a resistor. The output terminal of the final stage amplifier output circuit is also connected to the high-temperature segmented compensation circuit and the base of transistor Q3.

[0009] The high-temperature segmented compensation circuit includes a positive temperature input current mirror, an amplification unit, and a current extraction unit. The mirror current signal output terminal of the positive temperature input current mirror is connected through the amplification unit and the current extraction unit. The positive temperature extraction control signal of the reference voltage generation circuit serves as the control current signal of the positive temperature input current mirror.

[0010] The positive temperature input current mirror includes transistors Q14 and Q15 with their bases connected together. The emitter of transistor Q14 is connected to the power supply VIN through resistor R12, and its base is connected to the common base and collector of the current mirror. The collector serves as the connection point for the positive temperature extraction control signal. The emitter of transistor Q15 is connected to the power supply VIN through resistor R17, and its collector serves as the output terminal and is grounded through adjustable resistor R13.

[0011] The amplification unit includes:

[0012] The base of transistor Q16 is connected to the common base of the positive temperature input current mirror, and the emitter is connected to the power supply VIN through resistor R17.

[0013] Transistor Q18 has its base connected to the output terminal of the positive temperature input current mirror, its collector connected to the collector of transistor Q16, and its emitter grounded through resistor R14.

[0014] The base of transistor Q17 is connected to the common base of the positive temperature input current mirror, the emitter is connected to the power supply through resistor R17, and the collector is used as the output terminal of the amplification unit.

[0015] Transistor Q19 has its base connected to the collector of transistor Q16, its collector connected to the collector of transistor Q17, and its emitter grounded through resistor R14.

[0016] The current extraction unit includes transistors Q20 and Q21. The collector and base of transistor Q20 are connected to the output of the amplifier unit, and the emitter is connected to the emitter of transistor Q21 through resistor R15.

[0017] The base of transistor Q21 is connected to the base of transistor Q20, the emitter is grounded through resistor R16, and the collector is connected to the current input terminal VF.

[0018] The load drive circuit includes:

[0019] The collector of transistor Q22 is connected to the power supply VIN through resistor R18, and the base is connected to the control signal input terminal.

[0020] Transistor Q24 has its emitter connected to the power supply VIN, its base and collector shorted together, and its collector connected to the emitter of Q23 through resistor R19.

[0021] The base of transistor Q23 is connected to the emitter of Q22;

[0022] Transistor Q25 has its collector and base connected to the emitter of Q23, and its emitter is grounded through resistors R20 and R21.

[0023] Transistor Q26 has its base connected to the base of transistor Q25, its emitter grounded through resistor R21, and its collector connected to the first output terminal VD.

[0024] The base and emitter of transistor Q27 are connected to the first output terminal VD, and the emitter is connected to the power supply VIN through resistor R22.

[0025] The base of transistor Q28 is connected to the base of transistor Q24, and the emitter is connected to the power supply VIN.

[0026] Transistor Q29 has its emitter connected to power supply VIN via resistor R23, and its base and collector connected to the collector of transistor Q28.

[0027] Transistor Q30 has its emitter connected to power supply VIN and its base connected to the base of transistor Q29.

[0028] Transistor Q31 has its collector connected to the collector of transistor Q29, its emitter grounded through resistor R24, and its base used as the bias voltage input.

[0029] Transistor Q32 has its emitter grounded through resistor R25, and its base and collector connected to the collector of transistor Q30. The collector is connected to the second output terminal VE.

[0030] The final stage amplifier output circuit includes:

[0031] Transistor Q1 has its emitter connected to the power supply VIN, its base connected to the first output terminal VD of the load drive circuit, and its collector connected to the final stage output terminal.

[0032] Transistor Q2 has its collector connected to the final stage output terminal, its base connected to the second output terminal VE of the load drive circuit, and its emitter grounded.

[0033] The final stage output is grounded through resistors R4 and R5 connected in series, and the connection point of resistors R4 and R5 is connected to the current extraction input terminal VF.

[0034] The base of transistor Q3 is connected to the current extraction input terminal VF, and the collector is grounded.

[0035] The final stage output is connected to the emitter of transistor Q3 through resistors R1, R2 and R3 connected in series. The connection point of resistors R1 and R2 is connected to the first differential input terminal VA of the reference voltage generation circuit, and the connection point of resistors R2 and R3 is connected to the second differential input terminal VB of the reference voltage generation circuit.

[0036] This invention integrates high input voltage tolerance and high common-mode rejection capability, requiring no additional components, reducing the number of components in the system (eliminating LDOs, large capacitors, optocouplers, etc.), lowering PCB layout complexity, improving system reliability, reducing component failure points, and lowering system cost. Compared with traditional bandgap reference circuits, this invention features a wide power supply voltage range, low temperature drift, high accuracy, and low process dependence. This invention can achieve adjustable temperature inflection point compensation by changing the resistance value of resistor R13 based on the measured temperature drift curve of the reference chip's output, supporting a maximum operating temperature of 175℃. The power supply voltage range VIN of this invention can support up to 40V, with a high power supply rejection ratio. When applied at the system board level, it eliminates the need for additional linear regulators, large capacitors, and optocouplers, significantly reducing system complexity and failure points. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the overall circuit structure of the present invention.

[0038] Figure 2 This is a circuit diagram of the reference voltage generation circuit of the present invention.

[0039] Figure 3 This is the circuit diagram of a high-temperature segmented compensation circuit.

[0040] Figure 4 This is a circuit diagram of a load drive circuit. Detailed Implementation

[0041] The present invention mainly includes a reference voltage generation circuit, a load driving circuit, a high temperature segmented compensation circuit, a resistor circuit, and transistors Q1, Q2, and Q3.

[0042] To achieve a wide input voltage range (VIN), the high-precision reference circuit differs from the traditional bandgap structure by having two power rails: VREF and VIN. The circuit using VREF as the power rail includes resistors R1, R2, R3, R4, and R5, transistor Q3, and part of the reference voltage circuit. It utilizes the negative temperature coefficient of the PN junction diode of the base-emitter voltage VBE of transistor Q3, which is superimposed with the positive temperature coefficient of the base-emitter voltage difference (ΔVBE) between Q4 and Q5 in the reference voltage generation circuit, to achieve first-order temperature compensation. ΔVBE is generated by utilizing the virtual short input characteristic of the five-transistor op-amp composed of Q4, Q5, R6, R7, and Q11. The voltage drop across resistor R2 is exactly equal to ΔVBE, so the current flowing through resistor R2 has a positive temperature coefficient. The reference voltage output VREF is equal to the voltage drops across resistors R1, R2, and R3, superimposed with the VBE voltage of transistor Q3, and then superimposed with the voltage drop across resistor R5. The circuitry around the VIN power rail is solely responsible for the load drive circuitry and the Class AB output transistor, providing a fast-response, high-current output capability. Simply put, VREF generation is independent of the VIN voltage, thus satisfying the requirement for a wide power supply voltage range.

[0043] This invention employs two advanced temperature compensation methods. First, it utilizes the different temperature characteristics of different resistors, splitting resistor R1 to achieve simple second-order compensation of the reference voltage's temperature characteristics. Second, the high-temperature segmented temperature compensation uses current I2 to draw current flowing through resistor R4, changing the voltage drop across resistor R5, thereby achieving VREF output drift compensation at different temperature inflection points. The high-temperature segmented compensation circuit utilizes a positive temperature current I... PTAT The voltage drop across the adjustable resistor R13 is mirrored to an adjustable voltage drop. As the voltage drop across R13 increases with temperature, transistor Q18 turns on, Q19 enters the cutoff region, and transistor Q20 turns on, allowing current to flow. This current is mirrored to transistor Q21, ultimately achieving high-order compensation at the adjustable temperature inflection point. The magnitude of the compensation current can be adjusted by changing I. PTAT This can reduce reliance on wafer fabrication process devices to some extent.

[0044] See Figure 1The negative terminals VA and VB of resistor R1 and R2 serve as the input signals for the reference voltage generation module. Resistors R1, R2, and R3 are connected in series to the emitter of transistor Q3. The collector of Q3 is connected to ground, and its base is connected to the positive terminal of resistor R5. The other end of resistor R5 is also connected to ground. The negative terminal of resistor R4 is connected to resistor R5, and its other end is connected to the reference voltage output VREF. The other end of resistor R1 is connected to the reference voltage output VREF. The reference voltage output VREF also serves as the power rail for part of the circuitry of the reference voltage generation module. The wide power supply voltage VIN of the reference circuit serves as the power rail, providing operating voltage for the reference voltage generation module, the load drive circuit, the high-temperature segmented compensation circuit, and transistors Q1 and Q2. The emitter of transistor Q1 is connected to VIN, its base is connected to the output VD of the load drive circuit, and its collector is connected to the collector of transistor Q2, and also connected to the output VREF of the reference circuit. The base of Q2 is connected to the output VE of the load drive circuit, and its emitter is connected to ground. The reference voltage generation circuit provides a positive temperature current IPTAT to the high temperature segment compensation circuit. The input / output terminals of the high temperature segment compensation circuit are connected to the base VF of transistor Q3.

[0045] See Figure 2 Voltages VA and VB, as input signals, are connected to the bases of transistors Q4 and Q5, respectively. The emitters of Q4 and Q5 are connected together and also connected to the collector of transistor Q11. The collectors of transistors Q4 and Q5 are connected to the negative terminals of resistors R6 and R7, respectively. The positive terminals of the two resistors are connected together and connected to the power rail VREF. The negative terminals of resistors R6 and R7 are connected to the bases of transistors Q6 and Q7, respectively. The emitters of Q6 and Q7 are connected together and also connected to the collector of transistor Q12. The collectors of Q6 and Q7 are connected to the collectors of transistors Q8 and Q9, respectively. The collector and base of Q8 are connected to the base of Q9, and the emitters of Q8 and Q9 are connected together and connected to the power rail VIN. The collector of transistor Q9 is connected to the base of transistor Q10 and the positive terminal of resistor R8. The emitter of Q10 is connected to the power rail VIN. The collector of Q10 is connected to the lower plate of capacitor C1, and the upper plate of C1 is connected to the negative terminal of resistor R8. The collector of transistor Q10 is connected to the collector of Q13, and the output voltage is VC, which is provided as an output signal to the load drive circuit. The positive terminals of resistors R9, R10, and R11 are connected to the emitters of transistors Q11, Q12, and Q13, respectively, and their negative terminals are all connected to ground. The positive terminal of resistor RP is connected to the emitter of transistor QP, and its negative terminal is connected to ground. The collector of transistor QP is the module output pin, used to provide the positive temperature current signal I. PTAT ,exist Figure 3 In the diagram, this pin is connected to the collector of transistor Q14.

[0046] The voltage drop across resistor R2 is the base-emitter voltage difference between Q4 and Q5, i.e.

[0047] △VBE 4，5 The current flowing through R2 is Then the reference circuit output If we ignore the effects of the base current of transistor Q3 and the input / output current I2 of the high-temperature segmented compensation circuit on resistors R4 / R5, the voltage... Substituting this equation into the equation for the output VREF of the reference circuit, we have: This equation shows that the output VREF of the reference circuit is independent of VIN over a wide power supply voltage range.

[0048] The base current of transistor Q3 flows through resistor R5. The base current also has temperature characteristics, which can compensate for the output temperature drift to a certain extent. If the VREF temperature drift curve does not require the base current of Q3 to compensate for the temperature drift, the base mirror compensation circuit can be used to eliminate the influence on the voltage drop of resistor R5. Since the base mirror compensation circuit is not in this invention, it will not be described here.

[0049] In the circuit, resistors R1, R2, R3, R4, and R5 can be of the same type, such as polysilicon resistors or metal thin-film resistors. If high-order temperature compensation is required, resistor R1 can be split, and resistors with different temperature characteristics can be connected in a resistor string to achieve the desired result.

[0050] Figure 3 This is a schematic diagram of the high-temperature segmented compensation circuit of the present invention. The positive terminal of resistor R12 is connected to the power supply VIN, and the negative terminal is connected to the emitter of transistor Q14. The base and collector of Q14 are connected to the bases of transistors Q15, Q16, and Q17. The collector of transistor Q15 is connected to the positive terminal of variable resistor R13 and also to the base of transistor Q18. The collector of Q18 is connected to the collector of Q16 and the base of Q19. The collector of Q19 is connected to the collector of Q17 and the collector of Q20. The emitters of Q18 and Q19 are connected to the positive terminal of resistor R14. The emitter of transistor Q20 is connected to the positive terminal of resistor R15. The base of Q20 is connected to the base of transistor Q21. The emitter of Q21 is connected to the negative terminal of resistor R15 and also to the positive terminal of R16. The negative terminals of variable resistor R13, resistors R14, and R16 are all connected to ground potential. The emitters of transistors Q15, Q16, and Q17 are connected to the negative terminal of resistor R17, and the positive terminal is connected to the power supply VIN.

[0051] Positive temperature current I PTAT This will be mirrored onto the branch connecting transistor Q15 and variable resistor R13, and the voltage drop across resistor R13 will be... The base voltage of transistor Q18 increases with increasing temperature. When it increases sufficiently, it can turn on transistor Q18, causing the base voltage of Q19 to gradually decrease, thus bringing Q19 into the cutoff region. Meanwhile, the base voltage of Q20 increases. As the temperature rises, VBE... Q20 As the current increases, more current gradually flows in. The current mirror formed by transistors Q20 and Q21 will mirror the current to I2. Current I2 will draw current from the adjacent... Figure 1 The current flowing through resistor R4 will no longer flow into resistor R5, thus changing the voltage drop across R5. By controlling the value of the variable resistor R13, the compensation temperature point can be set according to the VREF temperature drift curve; by adjusting I... PTAT The magnitude of the current can alter the compensation effect, thereby obtaining the VREF (velocity of free drift) at low temperatures. This novel high-temperature segmented compensation method features a simple circuit principle, low dependence on manufacturing processes, and effectively improves the accuracy of the reference circuit output.

[0052] Figure 4 This is a schematic diagram of the load drive circuit of the present invention. The VC signal output from the reference voltage generation circuit is connected to the base of transistor Q22. The emitter of Q22 is connected to the base of transistor Q23. The collector of Q22 is connected to the negative terminal of resistor R18, and the positive terminal of R18 is connected to the power rail VIN. The emitter of transistor Q23 is connected to the negative terminal of R19. The positive terminal of R19 is connected to the base and collector of transistor Q24 and the base of transistor Q28. The emitter of Q24 is connected to the power rail VIN. The collector of transistor Q23 is connected to the collector and base of transistor Q25 and the base of transistor Q26. The emitter of Q25 is connected to the positive terminal of resistor R20, and the negative terminal is connected to the positive terminal of resistor R21 and the emitter of transistor Q26. Transistor Q26's collector is connected to the collector and base of transistor Q27, thus outputting the drive signal VD. The emitter of transistor Q27 is connected to the negative terminal of resistor R22, and the positive terminal of R22 is connected to the power rail VIN. Transistor Q28's emitter is connected to the power rail VIN, and its collector is connected to the base and collector of transistors Q29, Q31, and Q30. Transistor Q29's emitter is connected to the negative terminal of resistor R23, and its positive terminal is connected to the power rail VIN. Transistor Q31's base is connected to the bias Vbias1, its emitter is connected to the positive terminal of resistor R24, and its negative terminal is grounded. Transistor Q30's emitter is connected to the power rail VIN, and its collector is connected to the collector and base of transistor Q32, thus outputting the drive signal VE. Transistor Q32's emitter is connected to the positive terminal of resistor R25, and its negative terminal is grounded.

[0053] In summary, the high-precision reference circuit with a wide power supply voltage range in this invention features a flexible dual-rail power supply design that reuses the reference voltage and a high-temperature segmented compensation method. It effectively balances the characteristics of a wide power supply voltage range, low temperature drift, and high precision. The circuit design is flexible, highly reliable, and has low process dependence. It can be more widely used in the design of precision signal processing to provide the system with a high-precision and highly stable reference voltage, maximizing the accuracy of signal and data conversion.

Claims

1. A high-precision reference circuit with a wide power supply voltage range, characterized in that: It includes a reference voltage generation circuit, a high-temperature segmented compensation circuit, a load drive circuit, and a final stage amplifier output circuit; The reference voltage generating circuit outputs a positive temperature characteristic control signal to the load drive circuit and a positive temperature extraction control signal to the high temperature segment compensation circuit. The output terminal of the load drive circuit is connected to the final stage amplification output circuit, and the extraction current input terminal of the high temperature segment compensation circuit is connected to the output terminal of the final stage amplification output circuit.

2. The high-precision reference circuit with a wide power supply voltage range as described in claim 1, characterized in that, The reference voltage input terminal VREF of the reference voltage generation circuit is connected to the output terminal of the final stage amplifier output circuit. The two differential input terminals of the reference voltage generation circuit are connected to the voltage divider resistor string. The reference voltage input terminal is grounded through the voltage divider resistor string and transistor Q3. The output terminal of the final stage amplifier output circuit is grounded through a resistor. The output terminal of the final stage amplifier output circuit is also connected to the high-temperature segmented compensation circuit and the base of transistor Q3.

3. The high-precision reference circuit with a wide power supply voltage range as described in claim 2, characterized in that, The high-temperature segmented compensation circuit includes a positive temperature input current mirror, an amplification unit, and a current extraction unit. The mirror current signal output terminal of the positive temperature input current mirror is connected through the amplification unit and the current extraction unit. The positive temperature extraction control signal of the reference voltage generation circuit serves as the control current signal of the positive temperature input current mirror.

4. The high-precision reference circuit with a wide power supply voltage range as described in claim 3, characterized in that, The positive temperature input current mirror includes transistors Q14 and Q15 connected at their bases. The emitter of transistor Q14 is connected to the power supply VIN through resistor R12. The base is connected to the collector as the common base of the current mirror. The collector is used as the connection point for the positive temperature jacking control signal. The emitter of transistor Q15 is connected to the power supply VIN through resistor R17, and the collector, as the output terminal, is grounded through adjustable resistor R13.

5. The high-precision reference circuit with a wide power supply voltage range as described in claim 4, characterized in that, The amplification unit includes: The base of transistor Q16 is connected to the common base of the positive temperature input current mirror, and the emitter is connected to the power supply VIN through resistor R17. Transistor Q18 has its base connected to the output terminal of the positive temperature input current mirror, its collector connected to the collector of transistor Q16, and its emitter grounded through resistor R14. The base of transistor Q17 is connected to the common base of the positive temperature input current mirror, the emitter is connected to the power supply through resistor R17, and the collector is used as the output terminal of the amplification unit. Transistor Q19 has its base connected to the collector of transistor Q16, its collector connected to the collector of transistor Q17, and its emitter grounded through resistor R14.

6. The high-precision reference circuit with a wide power supply voltage range as described in claim 4, characterized in that, The current extraction unit includes transistors Q20 and Q21. The collector and base of transistor Q20 are connected to the output of the amplifier unit, and the emitter is connected to the emitter of transistor Q21 through resistor R15. The base of transistor Q21 is connected to the base of transistor Q20, the emitter is grounded through resistor R16, and the collector is connected to the current input terminal VF.

7. The high-precision reference circuit with a wide power supply voltage range as described in claim 6, characterized in that, The load drive circuit includes: The collector of transistor Q22 is connected to the power supply VIN through resistor R18, and the base is connected to the control signal input terminal. Transistor Q24 has its emitter connected to the power supply VIN, its base and collector shorted together, and its collector connected to the emitter of Q23 through resistor R19. The base of transistor Q23 is connected to the emitter of Q22; Transistor Q25 has its collector and base connected to the emitter of Q23, and its emitter is grounded through resistors R20 and R21. Transistor Q26 has its base connected to the base of transistor Q25, its emitter grounded through resistor R21, and its collector connected to the first output terminal VD. The base and emitter of transistor Q27 are connected to the first output terminal VD, and the emitter is connected to the power supply VIN through resistor R22. The base of transistor Q28 is connected to the base of transistor Q24, and the emitter is connected to the power supply VIN. Transistor Q29 has its emitter connected to power supply VIN via resistor R23, and its base and collector connected to the collector of transistor Q28. Transistor Q30 has its emitter connected to power supply VIN and its base connected to the base of transistor Q29. Transistor Q31 has its collector connected to the collector of transistor Q29, its emitter grounded through resistor R24, and its base used as the bias voltage input. Transistor Q32 has its emitter grounded through resistor R25, and its base and collector connected to the collector of transistor Q30. The collector is connected to the second output terminal VE. The final stage amplifier output circuit includes: Transistor Q1 has its emitter connected to the power supply VIN, its base connected to the first output terminal VD of the load drive circuit, and its collector connected to the final stage output terminal. Transistor Q2 has its collector connected to the final stage output terminal, its base connected to the second output terminal VE of the load drive circuit, and its emitter grounded. The final stage output is grounded through resistors R4 and R5 connected in series, and the connection point of resistors R4 and R5 is connected to the current extraction input terminal VF. The base of transistor Q3 is connected to the current extraction input terminal VF, and the collector is grounded. The final stage output is connected to the emitter of transistor Q3 through resistors R1, R2 and R3 connected in series. The connection point of resistors R1 and R2 is connected to the first differential input terminal VA of the reference voltage generation circuit, and the connection point of resistors R2 and R3 is connected to the second differential input terminal VB of the reference voltage generation circuit.

8. The high-precision reference circuit with a wide power supply voltage range as described in claim 1, characterized in that, The current drawn by the high-temperature segmented compensation circuit is positively correlated with the positive-temperature extraction control signal.

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