一种带曲率补偿的高精度带隙基准源

A Curvature-Compensated High Precision Bandgap Reference

基于SMIC 0.18μm CMOS工艺,设计了一款低温漂高PSRR的带隙基准电压源。采用全新的曲率补偿电路架构,使输出基准电压源具有超低温漂系数。采用共源共栅电流镜带负反馈的结构,提高了核心电路的PSRR。利用Cadence Spectre EDA软件对电路进行设计和仿真,结果表明,在-40℃-100℃温度范围内,电路的温漂系数仅为1.8×10-6/℃,电压变化范围小于0.3mV,在1.85-5V的宽电压范围内均能正常工作,电源抑制比在低频时高达-111dB,在1kHz时也达到-98.07dB,功耗仅为23.7μW,非常适合于高性能系统集成应用。

A low temperature-drift and high precision bandgap voltage reference was designed in the SMIC 0.18- /μW CMOS process. A new curvature compensated circuit structure was adopted, which had made the coefficient of the temperature-drift smaller. The structure of cascode current mirror with negative feedback was used to improve the PSRR of the core circuitry. It was designed and simulated by Cadence Spectre EDA software tools. The simulation results demonstrated that the temperature coefficient was only 1.8 × 10-6/℃ , and the voltage variation was less than 0.3 mV at the temperature range of --40 ℃ to 100 ℃. It could operate steadily with a wide supply voltage range of 1.85-5 V. The power supply rejection ratios of -- 111 dB and -- 98. 07 dB were achieved at low frequency and 1 kHz respectively. It consumed only 23.7 μW, which made it suitable for the applications of high performance system level integration.