CN-224232131-U - Band gap reference circuit with temperature compensation

Abstract

The utility model provides a bandgap reference circuit with temperature compensation. The band gap reference circuit comprises a band gap reference source circuit, a low temperature compensation circuit and a high temperature compensation circuit, wherein the band gap reference source circuit comprises a first transistor, the output end of the band gap reference source circuit provides reference voltage, the low temperature compensation circuit comprises a first operational amplification circuit, the first input end of the first operational amplification circuit receives first reference voltage, the second input end of the first operational amplification circuit is coupled with the first transistor, the high temperature compensation circuit comprises a second operational amplification circuit, the first input end of the second operational amplification circuit receives second reference voltage, the second input end of the first operational amplification circuit is coupled with the first transistor, when the temperature is lower than a low temperature threshold value, the first operational amplification circuit generates first compensation current for compensating the reference voltage of the band gap reference source circuit, and when the temperature is higher than a high temperature threshold value, the second operational amplification circuit generates second compensation current for compensating the reference voltage of the band gap reference source circuit. The bandgap reference circuit can inhibit drift of temperature on reference voltage. Meanwhile, the compensation mode is simple in structure, quantization precision can be improved, and dynamic characteristics and linearity of a quantization circuit result are optimized.

Inventors

• LIAO YONG
• YE JUN
• QIAN WENRONG
• LUO XUESONG

Assignees

• 厦门市必易微电子技术有限公司

Dates

Publication Date

20260512

Application Date

20250515

Claims (7)

1. 1. A bandgap reference circuit with temperature compensation, comprising: the band gap reference source circuit comprises a first transistor, wherein the output end of the band gap reference source circuit provides reference voltage; The low temperature compensation circuit comprises a first operational amplifier circuit, wherein a first input end of the first operational amplifier circuit receives a first reference voltage, a second input end of the first operational amplifier circuit is coupled with a first transistor, and The high-temperature compensation circuit comprises a second operational amplification circuit, wherein a first input end of the second operational amplification circuit receives a second reference voltage, and a second input end of the second operational amplification circuit is coupled with the first transistor; When the temperature is lower than the low temperature threshold value, the first operational amplifier circuit generates a first compensation current for compensating the reference voltage of the band gap reference source circuit, and when the temperature is higher than the high temperature threshold value, the second operational amplifier circuit generates a second compensation current for compensating the reference voltage of the band gap reference source circuit.
2. 2. The bandgap reference circuit of claim 1, wherein the bandgap reference source circuit includes a resistor through which a first compensation current flows to raise the reference voltage when the temperature is below the low temperature threshold, and through which a second compensation current flows to raise the reference voltage when the temperature is above the high temperature threshold.
3. 3. The bandgap reference circuit of claim 2, wherein the first operational amplifier circuit includes: a first compensation transistor, wherein the control terminal of the first compensation transistor receives a first reference voltage, the first terminal of the first compensation transistor is coupled to the power supply terminal, the second terminal of the first compensation transistor is coupled to the reference ground, and The control end of the second compensation transistor is coupled with the first end of the first transistor, the first end of the second compensation transistor is coupled with the resistor, the second end of the second compensation transistor is coupled with the reference ground, and the control end and the second end of the first transistor are coupled with the reference ground.
4. 4. A bandgap reference circuit as claimed in claim 3 wherein the first compensation transistor and the second compensation transistor comprise N-type metal oxide semiconductor field effect transistors (NMOS).
5. 5. The bandgap reference circuit of claim 2, wherein the second operational amplifier circuit includes two pairs of third and fourth compensation transistors.
6. 6. The bandgap reference circuit of claim 5, wherein the high temperature compensation circuit further comprises a current mirror, an input terminal of the current mirror being coupled to the output terminal of the second operational amplifier circuit, and an output terminal of the current mirror being coupled to the resistor.
7. 7. The bandgap reference circuit of claim 5, wherein the third compensation transistor and the fourth compensation transistor comprise P-type metal oxide semiconductor field effect transistors (PMOS).

Description

Band gap reference circuit with temperature compensation Technical Field The present utility model relates to the field of electronics, and in particular, but not exclusively, to a bandgap reference circuit with temperature compensation. Background The bandgap reference circuit provides a reference voltage, wherein the accuracy of the reference voltage is the most important indicator of the bandgap reference circuit. Fig. 1 shows a conventional bandgap reference circuit. The band gap reference circuit does not have a temperature compensation function, so that when the band gap reference circuit is applied with high precision, a larger variation range exists between the reference voltage VREF at high and low temperatures, and the quantization precision of a subsequent quantization circuit is affected. Particularly, in the high and low temperature states, the voltage deviation of the reference voltage VREF is large, which deteriorates the quantization accuracy of the subsequent circuits and affects the dynamic characteristics and linearity of the final result. Some existing bandgap reference circuits have temperature compensation circuits, but temperature compensation circuits are generally complex, resulting in increased chip cost. Therefore, there is a need for a bandgap reference circuit with temperature compensation and simple circuitry that can reduce chip cost and compensate for variations in reference voltage VREF due to temperature variations. Disclosure of utility model At least in view of one or more of the problems in the background art, the present utility model provides a bandgap reference circuit with temperature compensation. The band gap reference circuit comprises a band gap reference source circuit, a low temperature compensation circuit and a high temperature compensation circuit, wherein the band gap reference source circuit comprises a first transistor, the output end of the band gap reference source circuit provides reference voltage, the low temperature compensation circuit comprises a first operational amplification circuit, the first input end of the first operational amplification circuit receives first reference voltage, the second input end of the first operational amplification circuit is coupled with the first transistor, the high temperature compensation circuit comprises a second operational amplification circuit, the first input end of the second operational amplification circuit receives second reference voltage, the second input end of the second operational amplification circuit is coupled with the first transistor, when the temperature is lower than a low temperature threshold value, the first operational amplification circuit generates first compensation current for compensating the reference voltage of the band gap reference source circuit, and when the temperature is higher than the high temperature threshold value, the second operational amplification circuit generates second compensation current for compensating the reference voltage of the band gap reference source circuit. Optionally, the bandgap reference source circuit includes a resistor through which the first compensation current or the second compensation current flows to raise the reference voltage. Optionally, the first operational amplifier circuit comprises a first compensation transistor, wherein a control end of the first compensation transistor receives a first reference voltage, a first end of the first compensation transistor is coupled to the power supply end, a second end of the first compensation transistor is coupled to the reference ground, and a second compensation transistor, wherein a control end of the second compensation transistor is coupled to the first end of the first transistor, a first end of the second compensation transistor is coupled to the resistor, a second end of the second compensation transistor is coupled to the reference ground, and a control end and a second end of the first transistor are coupled to the reference ground. Optionally, the first compensation transistor and the second compensation transistor comprise N-type metal oxide semiconductor field effect transistors (NMOS). Optionally, the second operational amplifier circuit includes two pairs of third and fourth compensation transistors. Optionally, the high temperature compensation circuit further includes a current mirror, an input terminal of the current mirror is coupled to an output terminal of the second operational amplifier circuit, and an output terminal of the current mirror is coupled to the resistor. Optionally, the third compensation transistor and the fourth compensation transistor comprise P-type metal oxide semiconductor field effect transistors (PMOS). The band-gap reference circuit provided by the utility model can inhibit drift of temperature on reference voltage, and meanwhile, the compensation mode is simple in structure, can improve quantization precision, and optimizes dynamic characteristics a