Band-gap reference source circuit capable of adjusting convex curve temperature curvature compensation

Abstract

The invention relates to the technical field of integrated circuit design, in particular to a band-gap reference source circuit capable of adjusting convex curve temperature curvature compensation, which comprises a basic sub-1V band-gap reference circuit, a low-temperature curvature compensation circuit, a high-temperature curvature compensation circuit and a reference voltage output circuit. The reference voltage of a convex curve can be effectively compensated in a wide temperature range, the temperature drift of the reference voltage is improved, and meanwhile the design requirements for low voltage and low power consumption are met.

Description

Technical Field

[0001] The invention relates to the technical field of integrated circuit design, and in particular to a bandgap reference source circuit capable of adjusting convex curve temperature curvature compensation. Background Art

[0002] Bandgap reference sources are widely used in analog, digital and mixed signal circuits, especially in battery management systems (BMS), which require high-precision monitoring of battery cell voltage to calculate the battery's state of charge. In order to accurately measure the battery cell voltage over the full temperature operating range, a low-temperature drift reference voltage source is required, while also meeting the design requirements of low voltage and low power consumption. In order to achieve a reference voltage that is stable with temperature changes, bandgap references (BGRs) are widely used. Traditional bandgap reference sources are limited by the common collector structure of parasitic vertical bipolar junction transistors (BJTs), and the minimum power supply voltage must be higher than 1.25V, which cannot meet the requirements of contemporary battery-powered products for low voltage and low power consumption. In addition, the performance of BGRs will be severely degraded due to process variations and device mismatches, resulting in significant temperature drift problems, and the final output reference voltage may present a convex or concave curve in terms of temperature characteristics. Although a variety of temperature compensation technologies have been proposed to improve the temperature drift of the reference voltage, such as exponential curvature compensation and piecewise nonlinear compensation, it is still difficult to achieve high accuracy and high stability within a wide temperature range (-40°C to 140°C) while taking into account low voltage and low power consumption. Summary of the invention

[0003] The present invention provides a bandgap reference source circuit with a function of adjusting the temperature curvature compensation of a convex curve, which can effectively compensate for the reference voltage of the convex curve in a wide temperature range, improve the temperature drift of the reference voltage, and meet the design requirements of low voltage and low power consumption.

[0004] In order to achieve the purpose of the present invention, the technical solution adopted is: a bandgap reference source circuit with adjustable convex curve temperature curvature compensation, including a basic sub-1V bandgap reference circuit, a low temperature curvature compensation circuit, a high temperature curvature compensation circuit and a reference voltage output circuit; the basic sub-1V bandgap reference circuit is used to generate a positive temperature coefficient current I PT and negative temperature coefficient current I NT The low temperature curvature compensation circuit is used to generate a negative temperature coefficient compensation current I in the low temperature range NTC The high temperature curvature compensation circuit is used to generate a positive temperature coefficient compensation current I in a high temperature range. PTC The reference voltage output circuit is copied by a current mirror, and the positive temperature coefficient current I output by the basic sub-1V bandgap reference circuit is weighted. PT and negative temperature coefficient current I NT Synthesize preliminary temperature compensation reference current I ref , and then with the resistor ROUT Multiplication generates a reference voltage V with a convex curve characteristic. ref0 The reference voltage output circuit converts the negative temperature coefficient compensation current I NTC and positive temperature coefficient compensation current I PTC Superimpose and then add resistance R TC Multiply them to generate the low temperature compensation voltage V NTC And high temperature compensation voltage V PTC , achieving a reference voltage V based on a convex curve characteristic ref0 The segmented temperature curvature compensation finally obtains the reference voltage V that is independent of temperature. ref .

[0005] As an optimization solution of the present invention, the basic sub-1V bandgap reference circuit includes a PNP type BJT tube Q 1 、PNP type BJT tube Q 2 , operational amplifier OP1, operational amplifier OP2, PMOS tube M 1 、PMOS tube M 2 、PMOS tube M 3 , resistor R 1 and resistor R 2 , PNP type BJT tube Q 1 And PNP type BJT tube Q 2 The base and collector of the PNP BJT tube Q are connected together and connected to GND. 1 The emitters of are connected to the inverting input terminals of the operational amplifier OP1 and the inverting input terminals of the operational amplifier OP2. 2 The emitter of 2 The non-inverting input terminal of the operational amplifier OP2 is connected to the non-inverting input terminal of the operational amplifier OP1 through the resistor R 1 Connected to GND, PMOS tube M 1 The gate of the PMOS tube M is connected to the output terminal of the operational amplifier OP1. 1 The source and power supply V DD Connected, PMOS tube M 1 The drain of the PMOS tube M is connected to the same-direction input terminal of the operational amplifier OP1; 2 The gate of the PMOS tube M2 is connected to the output of the operational amplifier OP2, and the source of the PMOS tube M2 is connected to the power supply V DD Connected, PMOS tube M 2 The drain of the PMOS tube M is connected to the inverting input terminal of the operational amplifier OP2. 3 The gate of the PMOS tube M is connected to the output terminal of the operational amplifier OP2. 3 The source and power supply V DD Connected, PMOS tube M3 The drain of is connected to the non-inverting input terminal of the operational amplifier OP2.

[0006] As an optimization solution of the present invention, the low temperature curvature compensation circuit includes a PMOS tube M C1 、PMOS tube M C2 、PMOS tube M C3 、PMOS tube M C4 、NMOS tube M C5 and NMOS tube M C6 , PMOS tube MC 1 The gate of the PMOS tube M 1 The gate of PMOS tube M is connected to C1 The source and power supply V DD Connected, PMOS tube M C2 The gate of the PMOS tube M 3 The gate of PMOS tube M is connected to C2 The source and power supply V DD Connected, PMOS tube M C2 The drain of NMOS tube M C6 The drain of PMOS tube M C3 The source and power supply V DD Connected, PMOS tube M C3 The gate and drain are connected together and connected to the NMOS tube M C6 The drain of PMOS tube M C4 The gate of the PMOS tube M C3 The gate of PMOS tube M is connected to C4 The source and power supply V DD Connected, PMOS tube M C4 The drain of the reference voltage output circuit is connected to the temperature curvature compensation input terminal V TC Connected, NMOS tube M C5 The source of NMOS tube M is connected to GND. C5 The gate and drain are connected together and connected to the PMOS tube M C1 The drain of NMOS tube M C6 The gate of NMOS tube M C5 The gate of NMOS tube M is connected to C6 The source of is connected to GND.

[0007] As an optimization solution of the present invention, the PMOS tube M C1 With PMOS tube M 1 A 1:1 current mirror is formed to copy the negative temperature coefficient current I NT ; PMOS tube M C2 With PMOS tube M 3The current mirror of C1:1 is formed to copy the positive temperature coefficient current C of C1 multiplier. 1 I PT ; NMOS tube M C6 With NMOS tube M C5 The current mirror of C2:1 is formed to copy the negative temperature coefficient current C of C2 times 2 I NT ; Negative temperature coefficient compensation current I NTC Through the PMOS tube M C3 With PMOS tube M C4 The 1:C3 current mirror is formed to copy the negative temperature coefficient compensation current C of C3 multiple 3 I NTC , and further output to the temperature curvature compensation input terminal V of the reference voltage output circuit TC .

[0008] As an optimization solution of the present invention, the high temperature curvature compensation circuit includes a PMOS tube M C7 、PMOS tube M C8 、PMOS tube M C9 、PMOS tube M C10 、NMOS tube M C11 and NMOS tube M C12 , PMOS tube M C7 The gate of the PMOS tube M 3 The gate of PMOS tube M is connected to C7 The source and power supply V DD Connected, PMOS tube M C8 The gate of the PMOS tube M 1 The gate of PMOS tube M is connected to C8 The source and power supply V DD Connected, PMOS tube M C8 The drain of NMOS tube M C12 The drain of PMOS tube M C9 The source and power supply V DD Connected, PMOS tube M C9 The gate and drain are connected together and connected to the NMOS tube M C12 The drain of PMOS tube M C10 The gate of the PMOS tube M C9 The gate of PMOS tube M is connected to C10 The source and power supply V DD Connected, PMOS tube M C10 The drain of the reference voltage output circuit is connected to the temperature curvature compensation input terminal V TC Connected, NMOS tube M C11 The source of NMOS tube M is connected to GND.C11 The gate and drain are connected together and connected to the PMOS tube M C7 The drain of NMOS tube M C12 The gate of NMOS tube M C11 The gate of NMOS tube M is connected to C12 The source of is connected to GND.

[0009] As an optimization solution of the present invention, the PMOS tube M C7 With PMOS tube M 3 A 1:1 current mirror is formed to copy the positive temperature coefficient current I PT ; PMOS tube M C8 With PMOS tube M 1 The current mirror D1:1 is formed to copy the negative temperature coefficient current D1 with the D1 multiplier. 1 I NT ; NMOS tube M C12 With NMOS tube M C11 The current mirror D2:1 is formed to copy the positive temperature coefficient current D with the D2 multiplier. 2 I PT ; Positive temperature coefficient compensation current I PTC Through the PMOS tube M C9 With PMOS tube M C10 The 1:D3 current mirror formed by the tube copies the positive temperature coefficient compensation current D of D3 multiplier 3 I PTC , and further output to the temperature curvature compensation input terminal V of the reference voltage output circuit TC .

[0010] As an optimization solution of the present invention, the reference voltage output circuit includes a PMOS transistor M 4 、PMOS tube M 5 , resistor R 3 and resistor R TC , PMOS tube M 4 The gate of the PMOS tube M 3 The gate of PMOS tube M 4 The source and power supply V DD Connected, PMOS tube M 4 The drain and reference voltage V ref The output end is connected to the PMOS tube M 5 The gate of the PMOS tube M 1 The gate of PMOS tube M 5 The source and power supply V DD Connected, PMOS tube M 5 The drain and reference voltage V ref Connected, resistor R 3In series with the reference voltage V ref Output terminal and temperature curvature compensation input terminal V TC Between, the resistor R TC Connected in series to the temperature curvature compensation input terminal V TC Between 1 and GND.

[0011] As an optimization solution of the present invention, the PMOS tube M 4 With PMOS tube M 3 A proportional current mirror is formed to copy the positive temperature coefficient current I PT , PMOS tube M 5 With PMOS tube M 1 A proportional current mirror is formed to copy the negative temperature coefficient current I NT , the negative temperature coefficient compensation current C input from the low temperature curvature compensation circuit 3 I NTC And the positive temperature coefficient compensation current D input from the high temperature curvature compensation circuit 3 I PTC , through the resistor R TC Forming low temperature compensation voltage V NTC And high temperature compensation voltage V PTC , superimposed on the reference voltage V with a convex curve characteristic ref0 Output end.

[0012] The present invention has positive effects: 1) The present invention provides a sub-1V bandgap reference source circuit with adjustable convex curve temperature curvature compensation, adopts a piecewise linear compensation method in a wide temperature range, accurately compensates the reference voltage of the convex curve for temperature, and significantly reduces temperature drift. Experimental results show that within the temperature range of -40℃ to 140℃, the temperature coefficient (TC) can be as low as 1.67ppm / ℃, which is significantly improved compared with the prior art; 2) The present invention can work at a power supply voltage as low as 1.3V, meeting the low voltage requirements of battery-powered products; at a power supply voltage of 1.8V, the circuit power consumption is less than 20μA; measurement results show that the linear adjustment rate of the reference voltage in the low power supply voltage range of 1.3 to 1.8V is less than 0.08% / V, ensuring the stability and accuracy of the output voltage; using TSMC's standard 0.18μm, 1P6M, CMOS process, the chip active area is only 0.009mm². BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0014] Figure 1 is a system block diagram of the present invention; Figure 2 It is a circuit schematic diagram of the present invention. DETAILED DESCRIPTION

[0015] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0017] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0018] like Figure 1 As shown, the present invention comprises a basic sub-1V bandgap reference circuit, a low temperature curvature compensation circuit, a high temperature curvature circuit and a reference voltage output circuit. The basic sub-1V bandgap reference circuit is used to generate a positive temperature coefficient current I PT and negative temperature coefficient current I NT , and I PT and I NT The reference current I of the preliminary temperature compensation is synthesized according to the weight ratio ref , and then with the resistor R OUT Multiplication generates a reference voltage V with a convex curve characteristic. ref0 ; The low temperature curvature compensation circuit is used in the low temperature range, according to the positive temperature coefficient current I PT and negative temperature coefficient current I NT , generating a negative temperature coefficient compensation current I NTC , and then with the resistor R TC Multiply to generate low temperature compensation voltage V NTC ; The high temperature curvature compensation circuit is used in the high temperature range, according to the input positive temperature coefficient current I PT and negative temperature coefficient current I NT , generating a positive temperature coefficient compensation current I PTC , and then with the resistor R TC Multiply to generate high temperature compensation voltage V PTC Finally, the reference voltage output circuit generates a reference voltage V having a convex curve characteristic. ref0 The low temperature compensation voltage V NTC And high temperature compensation voltage V PTC Superposition is performed to achieve a reference voltage V with a convex curve characteristic. ref0 The segmented temperature curvature compensation finally obtains the reference voltage V that is independent of temperature. ref .

[0019] like Figure 2 As shown, the basic sub-1V bandgap reference circuit includes a PNP type BJT tube Q 1 、PNP type BJT tube Q 2 , operational amplifier OP1, operational amplifier OP2, PMOS tube M 1 、PMOS tube M 2 、PMOS tube M 3 , resistor R 1 and resistor R 2 Among them, the PNP type BJT tube Q 1 And PNP type BJT tube Q 2 The base and collector of the PNP BJT tube Q are connected together and connected to the ground GND. 1 The emitter of is connected to the inverting input of the operational amplifier OP1 and the inverting input of the operational amplifier OP2 at the same time, and the PNP type BJT tube Q 2 The emitter of 2 The non-inverting input terminal of the operational amplifier OP2 is connected to the non-inverting input terminal of the operational amplifier OP1 through the resistor R 1 The inverting input terminal of the operational amplifier OP1 is connected to the inverting input terminal of the operational amplifier OP2, and the PMOS tube M 1 The gate, source, and drain of the operational amplifier OP1 are connected to the output terminal, power supply V DD , the same-direction input terminal of the operational amplifier OP1 is connected, and the PMOS tube M 2 The gate, source, and drain of the operational amplifier OP2 are connected to the output terminal, power supply V DD , the reverse input terminal of the operational amplifier OP2 is connected, and the PMOS tube M 3 The gate, source, and drain of the operational amplifier OP2 are connected to the output terminal, power supply V DD , the same-direction input terminal of the operational amplifier OP2 is connected; according to the temperature characteristics of the bipolar transistor and the virtual short and virtual open characteristics of the operational amplifier, the resistor R 1 and R 2 The negative temperature coefficient current I NT and positive temperature coefficient current I PT , and then through the PMOS tube M 1 And PMOS tube M 3 The image is copied to the low-temperature curvature compensation circuit, high-temperature curvature compensation circuit and reference voltage output circuit of the next level for further processing.

[0020] like Figure 2 As shown, the low temperature curvature compensation circuit includes a PMOS tube M C1 、PMOS tube M C2 、PMOS tube MC3 、PMOS tube M C4 、NMOS tube M C5 、NMOS tube M C6 Among them, the PMOS tube M C1 The gate, source, and drain of the PMOS tube M in the basic sub-1V bandgap reference circuit are 1 The gate, power supply V DD 、NMOS tube M C5 The drain of PMOS tube M C2 The gate, source, and drain of the PMOS tube M in the basic sub-1V bandgap reference circuit are 3 The gate, power supply V DD 、NMOS tube M C6 The drain of PMOS tube M C3 The source and power supply V DD Connected, PMOS tube M C3 The gate and drain are connected together and connected to the NMOS tube M C6 The drain of PMOS tube M C4 The gate, source and drain of the PMOS tube M C3 The gate, power supply V DD , the temperature curvature compensation input terminal V of the reference voltage output circuit TC Connected, NMOS tube M C5 The source of NMOS tube M is connected to GND. C5 The gate and drain are connected together and connected to the PMOS tube M C1 The drain of NMOS tube M C6 The gate, source, and drain of the NMOS tube M C5 Gate, GND, PMOS tube M C2 The drain of PMOS tube M C1 Compared with the PMOS tube M in the basic sub-1V bandgap reference circuit 1 A 1:1 current mirror is formed to copy the negative temperature coefficient current I NT ; PMOS tube M C2 Compared with the PMOS tube M in the basic sub-1V bandgap reference circuit 3 The current mirror of C1:1 is formed to copy the positive temperature coefficient current C of C1 multiplier. 1 I PT ; NMOS tube M C6 With NMOS tube M C5 The current mirror of C2:1 is formed to copy the negative temperature coefficient current C of C2 times 2 I NT ; In the low temperature range, when the negative temperature coefficient current C 2 I NTGreater than the positive temperature coefficient current C 1 I PT According to Kirchhoff's current law, there will be a negative temperature coefficient compensation current I NTC From PMOS tube M C3 The drain of the NMOS tube M C6 , this negative temperature coefficient compensation current I NTC Through the PMOS tube M C3 With PMOS tube M C4 The 1:C3 current mirror formed by the tube copies the negative temperature coefficient compensation current C of C3 multiplier. 3 I NTC , and further output to the temperature curvature compensation input terminal V of the reference voltage output circuit TC ; In the medium and high temperature range, the negative temperature coefficient current C 2 I NT Less than the positive temperature coefficient current C 1 I PT The low temperature curvature compensation circuit does not work, and the PMOS tube M C3 With PMOS tube M C4 The temperature compensation range in the low temperature zone can be offset by adjusting the MOS tube size ratio coefficients C1 and C2 to achieve the temperature range range, and the amplitude of the low temperature compensation voltage can be adjusted by the ratio coefficient C3 and the resistor R TC to adjust.

[0021] like Figure 2 As shown, the high temperature curvature compensation circuit includes a PMOS tube M C7 、PMOS tube M C8 、PMOS tube M C9 、PMOS tube M C10 、NMOS tube M C11 、NMOS tube M C12 Among them, the PMOS tube M C7 The gate, source, and drain of the PMOS tube M in the basic sub-1V bandgap reference circuit are 3 The gate, power supply V DD 、NMOS tube M C11 The drain of PMOS tube M C8 The gate, source, and drain of the PMOS tube M in the basic sub-1V bandgap reference circuit are 1 The gate, power supply V DD 、NMOS tube M C12 The drain of PMOS tube M C9 The source and power supply V DD Connected, PMOS tube M C9 The gate and drain are connected together and connected to the NMOS tube M C12The drain of PMOS tube M C10 The gate, source and drain of the PMOS tube M C9 The gate, power supply V DD , the temperature curvature compensation input terminal V of the reference voltage output circuit TC Connected, NMOS tube M C11 The source of NMOS tube M is connected to GND. C11 The gate and drain are connected together and connected to the PMOS tube M C7 The drain of NMOS tube M C12 The gate, source, and drain of the NMOS tube M C11 The gate, GND, PMOS tube M C8 The drain of the PMOS tube M is connected. C7 Compared with the PMOS tube M in the basic sub-1V bandgap reference circuit 3 A 1:1 current mirror is formed to copy the positive temperature coefficient current I PT ; PMOS tube M C8 Compared with the PMOS tube M in the basic sub-1V bandgap reference circuit 1 The current mirror D1:1 is formed to copy the negative temperature coefficient current D1 with the ratio of D1. 1 I NT ; NMOS tube M C12 With NMOS tube M C11 The current mirror D2:1 is formed to copy the positive temperature coefficient current D with the D2 multiplier. 2 I PT ; In the high temperature range, when the positive temperature coefficient current D 2 I PT Greater than the negative temperature coefficient current D 1 I NT When, according to Kirchhoff's current law, there will be a positive temperature coefficient compensation current I PTC From PMOS tube M C9 The drain of the NMOS tube M C12 , further this positive temperature coefficient compensation current I PTC Through the PMOS tube M C9 With PMOS tube M C10 The 1:D3 current mirror formed by the tube copies the positive temperature coefficient compensation current D of D3 multiplier 3 I PTC , and further output to the temperature curvature compensation input terminal V of the reference voltage output circuit TC ; In the medium and low temperature range, the positive temperature coefficient current D 2 I PT Less than the negative temperature coefficient current D 1 I NT, the high temperature curvature compensation circuit does not work, PMOS tube M C9 With PMOS tube M C10 The temperature compensation range in the high temperature zone can be offset by adjusting the MOS tube size ratio coefficients D1 and D2 to achieve the temperature range range, and the amplitude of the high temperature compensation voltage can be adjusted by the ratio coefficient D3 and the resistor R TC to adjust.

[0022] like Figure 2 As shown, the reference voltage output circuit includes a PMOS tube M 4 、PMOS tube M 5 , resistor R 3 and resistor R TC Among them, the PMOS tube M 4 The gate, source, and drain of the PMOS tube M in the basic sub-1V bandgap reference circuit are 3 The gate, power supply V DD , reference voltage V ref The output end is connected to the PMOS tube M 5 The gate, source, and drain of the PMOS tube M in the basic sub-1V bandgap reference circuit are 1 The gate, power supply V DD , reference voltage V ref The output terminal is connected to the resistor R 3 In series with the reference voltage V ref Output terminal and temperature curvature compensation input terminal V TC Between, the resistor R TC Connected in series to the temperature curvature compensation input terminal V TC Between the PMOS tube M 4 And PMOS tube M 5 , respectively, with the PMOS tube M in the basic sub-1V bandgap reference circuit 3 And PMOS tube M 1 A proportional current mirror is formed to copy the positive temperature coefficient current I PT and negative temperature coefficient current I NT The two are superimposed to form the reference current I for preliminary temperature compensation. ref , and then further through the resistor R OUT (equal to the resistance R 3 With R TC The sum of the above) produces a reference voltage V with a convex curve characteristic. ref0 At the same time, the negative temperature coefficient compensation current C input from the low temperature curvature compensation circuit 3 I NTC And the positive temperature coefficient compensation current D input from the high temperature curvature compensation circuit 3 I PTC , through the resistor RTC Forming low temperature compensation voltage V NTC And high temperature compensation voltage V PTC , and then further superimposed on the reference voltage V with the convex curve characteristics ref0 The output end realizes effective compensation for the convex curve bandgap reference voltage, and finally obtains a reference voltage V that is independent of temperature. ref .

[0023] The basic sub-1V bandgap reference circuit uses a pair of BJT transistors and two operational amplifiers to form a positive temperature coefficient current I PT and negative temperature coefficient current I NT , and then copied and summed through the current mirror to form the reference current I for preliminary temperature compensation ref , and further with the reference voltage output section resistor R OUT Multiplying them produces a reference voltage V with a convex curve characteristic. ref0 Although at a certain temperature (T 0 ) achieves a zero temperature coefficient, but due to the V BE (base-emitter voltage) and V T The nonlinear temperature characteristic of (thermal voltage) causes the temperature characteristic of the output reference voltage to present a concave-convex curve shape as a whole. The present invention specifically performs segmented temperature curvature compensation for the bandgap reference voltage of the convex curve. The temperature compensation circuit is divided into two parts: a low temperature curvature compensation circuit and a high temperature curvature compensation circuit. The appropriate positive temperature coefficient compensation current I is generated in different temperature ranges. PTC and negative temperature coefficient compensation current I NTC , and then with the reference voltage output part resistor R TC Multiply the low temperature compensation voltage V NTC And high temperature compensation voltage V PTC , and superimposed to the reference voltage V with a convex curve characteristic ref0 The output terminal finally obtains a high-precision reference voltage V that is independent of temperature. ref .

[0024] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A bandgap reference source circuit with a function of adjusting the temperature curvature compensation of a convex curve, characterized in that: The invention comprises a basic sub-1V bandgap reference circuit, a low temperature curvature compensation circuit, a high temperature curvature compensation circuit and a reference voltage output circuit; the basic sub-1V bandgap reference circuit is used to generate a positive temperature coefficient current I PT and negative temperature coefficient current I NT The low temperature curvature compensation circuit is used to generate a negative temperature coefficient compensation current I in the low temperature range NTC The high temperature curvature compensation circuit is used to generate a positive temperature coefficient compensation current I in a high temperature range. PTC The reference voltage output circuit is copied by a current mirror, and the positive temperature coefficient current I output by the basic sub-1V bandgap reference circuit is weighted. PT and negative temperature coefficient current I NT Synthesize preliminary temperature compensation reference current I ref , and then with the resistor R OUT Multiplication generates a reference voltage V with a convex curve characteristic. ref0 The reference voltage output circuit converts the negative temperature coefficient compensation current I NTC and positive temperature coefficient compensation current I PTC Superimpose and then add resistance R TC Multiply them to generate the low temperature compensation voltage V NTC And high temperature compensation voltage V PTC , achieving a reference voltage V based on a convex curve characteristic ref0 The segmented temperature curvature compensation finally obtains the reference voltage V that is independent of temperature. ref .

2. A bandgap reference source circuit with adjustable convex curve temperature curvature compensation according to claim 1, characterized in that: The basic sub-1V bandgap reference circuit includes a PNP BJT tube Q1, a PNP BJT tube Q2, an operational amplifier OP1, an operational amplifier OP2, a PMOS tube M1, a PMOS tube M2, a PMOS tube M3, a resistor R1 and a resistor R2. The base and collector of the PNP BJT tube Q1 and the PNP BJT tube Q2 are connected together and connected to GND. The emitter of the PNP BJT tube Q1 is connected to the inverting input terminal of the operational amplifier OP1 and the inverting input terminal of the operational amplifier OP2. The emitter of the PNP BJT tube Q2 is connected to the non-inverting input terminal of the operational amplifier OP2 through the resistor R2. The non-inverting input terminal of the operational amplifier OP1 is connected to GND through the resistor R1. The gate of the PMOS tube M1 is connected to the output terminal of the operational amplifier OP1. The source of the PMOS tube M1 is connected to the power supply V DD The drain of the PMOS tube M1 is connected to the same-direction input terminal of the operational amplifier OP1; the gate of the PMOS tube M2 is connected to the output terminal of the operational amplifier OP2, and the source of the PMOS tube M2 is connected to the power supply V DD The drain of the PMOS tube M2 is connected to the reverse input terminal of the operational amplifier OP2, the gate of the PMOS tube M3 is connected to the output terminal of the operational amplifier OP2, and the source of the PMOS tube M3 is connected to the power supply V DD The drain of the PMOS tube M3 is connected to the non-inverting input terminal of the operational amplifier OP2.

3. A bandgap reference source circuit with adjustable convex curve temperature curvature compensation according to claim 2, characterized in that: The low temperature curvature compensation circuit includes a PMOS tube M C1 、PMOS tube M C2 、PMOS tube M C3 、PMOS tube M C4 、NMOS tube M C5 and NMOS tube M C6 The gate of PMOS tube MC1 is connected to the gate of PMOS tube M1. C1 The source of the PMOS tube M is connected to the power supply VDD. C2 The gate of the PMOS tube M3 is connected to the gate of the PMOS tube M C2 The source and power supply V DD Connected, PMOS tube M C2 The drain of NMOS tube M C6 The drain of PMOS tube M C3 The source and power supply V DD Connected, PMOS tube M C3 The gate and drain are connected together and connected to the NMOS tube M C6 The drain of PMOS tube M C4 The gate of the PMOS tube M C3 The gate of PMOS tube M is connected to C4 The source and power supply V DD Connected, PMOS tube M C4 The drain of the reference voltage output circuit is connected to the temperature curvature compensation input terminal V TC Connected, NMOS tube M C5 The source of NMOS tube M is connected to GND. C5 The gate and drain are connected together and connected to the PMOS tube M C1 The drain of NMOS tube M C6 The gate of NMOS tube M C5 The gate of NMOS tube M is connected to C6 The source of is connected to GND.

4. A bandgap reference source circuit with adjustable convex curve temperature curvature compensation according to claim 3, characterized in that: PMOS tube M C1 It forms a 1:1 current mirror with the PMOS tube M1 to copy the negative temperature coefficient current I NT ; PMOS tube M C2 It forms a current mirror C1:1 with the PMOS tube M3 to copy the positive temperature coefficient current C1I with the C1 multiplier PT ; NMOS tube M C6 With NMOS tube M C5 The current mirror of C2:1 is formed to copy the negative temperature coefficient current C2I of C2 multiplier NT ; Negative temperature coefficient compensation current I NTC Through the PMOS tube M C3 With PMOS tube M C4 The 1:C3 current mirror is formed to copy the negative temperature coefficient compensation current C3I of C3 multiple NTC , and output to the temperature curvature compensation input terminal V of the reference voltage output circuit TC .

5. A bandgap reference source circuit with adjustable convex curve temperature curvature compensation according to claim 4, characterized in that: The high temperature curvature compensation circuit includes a PMOS tube M C7 、PMOS tube M C8 、PMOS tube M C9 、PMOS tube M C10 、NMOS tube M C11 and NMOS tube M C12 , PMOS tube M C7 The gate of the PMOS tube M3 is connected to the gate of the PMOS tube M C7 The source and power supply V DD Connected, PMOS tube M C8 The gate of the PMOS tube M1 is connected to the gate of the PMOS tube M C8 The source and power supply V DD Connected, PMOS tube M C8 The drain of NMOS tube M C12 The drain of PMOS tube M C9 The source and power supply V DD Connected, PMOS tube M C9 The gate and drain are connected together and connected to the NMOS tube M C12 The drain of PMOS tube M C10 The gate of the PMOS tube M C9 The gate of PMOS tube M is connected to C10 The source and power supply V DD Connected, PMOS tube M C10 The drain of the reference voltage output circuit is connected to the temperature curvature compensation input terminal V TC Connected, NMOS tube M C11 The source of NMOS tube M is connected to GND. C11 The gate and drain are connected together and connected to the PMOS tube M C7 The drain of NMOS tube M C12 The gate of NMOS tube M C11 The gate of NMOS tube M is connected to C12 The source of is connected to GND.

6. A bandgap reference source circuit with adjustable convex curve temperature curvature compensation according to claim 5, characterized in that: PMOS tube M C7 It forms a 1:1 current mirror with the PMOS tube M3 to copy the positive temperature coefficient current I PT ; PMOS tube M C8 It forms a current mirror D1:1 with the PMOS tube M1, and copies the negative temperature coefficient current D1I with the D1 multiple. NT ; NMOS tube M C12 With NMOS tube M C11 The current mirror D2:1 is formed to copy the positive temperature coefficient current D2I with the D2 multiplier PT ; Positive temperature coefficient compensation current I PTC Through the PMOS tube M C9 With PMOS tube M C10 The 1:D3 current mirror formed by the tube copies the positive temperature coefficient compensation current D3I with D3 multiplication factor. PTC , and output to the temperature curvature compensation input terminal V of the reference voltage output circuit TC .

7. A bandgap reference source circuit with adjustable convex curve temperature curvature compensation according to claim 6, characterized in that: The reference voltage output circuit includes a PMOS tube M4, a PMOS tube M5, a resistor R3 and a resistor R TC The gate of the PMOS tube M4 is connected to the gate of the PMOS tube M3, the source of the PMOS tube M4 is connected to the power supply VDD, and the drain of the PMOS tube M4 is connected to the reference voltage V ref The output end is connected, the gate of PMOS tube M5 is connected to the gate of PMOS tube M1, and the source of PMOS tube M5 is connected to the power supply V DD The drain of PMOS tube M5 is connected to the reference voltage V ref The output terminal is connected, and the resistor R3 is connected in series with the reference voltage V ref Output terminal and temperature curvature compensation input terminal V TC Between, the resistor R TC Connected in series to the temperature curvature compensation input terminal V TC Between 1 and GND.

8. A bandgap reference source circuit with adjustable convex curve temperature curvature compensation according to claim 7, characterized in that: PMOS tube M4 and PMOS tube M3 form a proportional current mirror to copy the positive temperature coefficient current I PT , PMOS tube M5 and PMOS tube M1 form a proportional current mirror to copy the negative temperature coefficient current I NT , the negative temperature coefficient compensation current C3I input from the low temperature curvature compensation circuit NTC And the positive temperature coefficient compensation current D3I input from the high temperature curvature compensation circuit PTC , through the resistor R TC Forming low temperature compensation voltage V NTC And high temperature compensation voltage V PTC , superimposed on the reference voltage V with a convex curve characteristic ref0 Output end.

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