一种高精度超低功耗基准电压源

A High Precision and Ultra Low Power Voltage Reference Source

提出了一种超低功耗、无BJT的基于亚阈值CMOS特性的基准电压源。采用正负温度系数电流求和的方式来获得与温度无关的电流,再转换成基准电压;采用共源共栅电流镜来提高电源电压抑制比和电压调整率。基于SMIC 0.18μm CMOS工艺进行仿真,结果表明,在-20℃~135℃温度范围内,温漂系数为2.97×10^(-5)/℃;在0.9~3.3V电源电压范围内,电压调整率为0.089%;在频率为100Hz时,电源电压抑制比为-74dB,电路功耗仅有230nW。

An ultra low power dissipation voltage reference source without BJT based on sub-threshold characteristic of CMOS was presented. The current which was independent of temperature was obtained by the sum of currents with negative and positive temperature coefficients, and then converted into a reference voltage. A cascode current mirror was used to increase the power supply rejection ratio （PSRR） and reduce the line sensitivity of the circuit. Based on SMIC 0. 18 μm CMOS process, the simulated results showed that the voltage＇s temperature coefficient was 2.97 10^-5/℃ at a temperature range from-20 ℃ to 135 ℃. The line sensitivity was 0. 089% at a supply voltage range from 0.9 to 3.3 V. The PSRR was-74 dB at 100 Hz frequency. The power dissipation of the circuit was only 230 nW.