一种分段补偿带隙基准电压源的设计

The Design of a Piecewise Compensated Bandgap Voltage Reference

针对一阶温度补偿的基准电压源仍有较高的温度系数的问题,本文提出一种分段补偿的设计方法,以降低基准电压源输出电压随温度的漂移。利用带负电阻放大器的增益对温度敏感的特性产生一个随温度变化的电压信号,用该电压信号驱动一个PMOS管在3个温度段内对基准电路注入或抽取电流的方式进行分段补偿。仿真结果表明:当温度在-40~125℃范围内变化时,基准电压仅变化0.311mV,温度系数为1.89×10-6℃^(-1),电源抑制比在低频时为-90dB。该带隙基准源在温度为-15℃、34℃、76℃时,基准电压对温度的函数曲线的的曲率为0,在标准工艺下温漂系数较低。该研究可为ADC、线性稳压器、DC/DC转换器等电路提供高精度的基准电压。

For first-order temperature compensation of the reference voltage source is still high temperature coefficient, this paper proposes a design method of piecewise compensation to reduce the temperature drift. A voltage signal following the temperature variation is produced by an amplifier with negative resistance of which gain is sensitive to temperature. Drived by this voltage signal, a PMOS transistor is used to inject or extract electricity current for the reference circuit in three temperature segments as a pattern of piecewise compensation. The simulation results indicate that the reference voltage of circuit only change 0. 311 mV and its temperature coefficient is 1.89 × 10-6℃-1 in the temperature range（TR） from -40 ℃ to 125 ℃. Its PSRR is -90 dB at low frequency. When the temperature of the bandgap reference voltage source is at -15 ℃, 34 ℃ and 76 ℃, the curvature of the reference voltage to the temperature is 0, and the temperature drift coefficient is lower in the standard process： The study can provide a high precision voltage reference for ADC, linear voltage regulator and DC/DC converter circuit.