低温度系数高电源抑制比宽频带带隙基准电压源的设计

Design of a Bandgap Reference with Low Temperature Coefficient High PSRR and Wide Band

本文设计了一款低温度系数高电源抑制比的带隙基准电压源。设计采用动态阈值MOS管(DTMOS)产生温度补偿电流,以降低温漂;输出部分采用一个简单的低通滤波器,以降低高频噪声,在较宽频带内提高电源抑制比。电路采用SMIC 0.18μm标准CMOS工艺实现,供电电源为1.8V,仿真结果表明:电路在-40～130℃温度范围内,温度系数为1.54×10-6℃-1,输出基准电压为1.154V,电源抑制比在10Hz处为-76dB,在100kHz处为-85dB,在15 MHz处为-63dB。本基准源具有较好的综合性能,可为数模转换电路、模数转换电路、电源管理芯片等提供高精度的基准电压,具有较大的应用价值。

A low temperature coefficient and high PSRR bandgap reference is presented in this paper.To temperature drift,a dynamic threshold MOS transistor is used to provide compensation current.A compact low-pass filter is introduced,the noise at high frequencies is reduced,and then a high PSRR over a wide frequency range is achieved.The proposed reference is implemented in SMIC 0.18μm CMOS process.The simulation results show that the temperature coefficient is 1.54×10^-6℃^-1,and an output reference voltage is1.154V for temperatures from -40℃ to 130℃ with supply voltage1.8V.The PSRR is-76dB at 10Hz,-85dB at 100kHz,and -63dB at 15MHz.The reference source has good comprehensive performance,which can provide high-precision reference voltage for digital-to-analog conversion circuit,analog-to-digital conversion circuit and power management chip,and has great application value.