宽温度范围高精度基准电压源设计

Design of a wide-temperature-range and high-precision voltage reference

针对传统Brokaw型带隙基准电压源温度系数较高的问题,采用高阶曲率补偿方法,利用PN结反向饱和电流随温度敏感变化的原理,通过将与基准电压温度系数呈相反趋势的补偿电流注入到基准核心部分,对基准输出电压进行温度补偿,实现了宽温度范围内基准电压源的高精度输出。电路基于0.18μm BCD工艺设计。仿真结果表明,在3.3 V电源电压下,基准输出电压为1.978 V,在-40~+150℃温度范围内,基准电压的温度系数为5.82×10^(-6)/℃,低频时电源抑制比(PSRR)为79.4 dB。

A high-order curvature compensation method was used to solve the problem of high temperature coefficient of the traditional Brokaw bandgap reference.Since the reverse saturation current of PN junction changes sensitively with temperature and its trend with temperature is opposite to the reference voltage,it was inputed into the core part of the reference as the compensation current,and the temperature compensation of the output voltage was realized.As a result,a high precision output of the reference was obtained over a wide temperature range.The circuit was designed based on 0.18μm BCD process.The simulation results show that the output voltage is 1.978 V under 3.3 V supply voltage.The temperature coefficient of the reference voltage is 5.82×10^(-6)/℃in the temperature range of-40~+150℃.The PSRR is 79.4 dB at low frequency.