一种高精度CMOS带隙基准电路的设计

采用ASMC0.35μm CMOS工艺设计了低功耗、高电源抑制比(PSRR)、低温漂、输出1V的带隙基准源电路。该设计中,偏置电压采用级联自偏置结构,运放的输出作为驱动的同时也作为自身电流源的驱动,实现了与绝对温度成正比(PTAT)温度补偿。通过对其进行仿真验证,当温度在-40～125℃和电源电压在1.6～5V时,输出基准电压具有3.68×10-6/℃的温度系数,Vref摆动小于0.094mV;在低频时具有-114.6dB的PSRR,其中在1kHz时为-109.3dB,在10kHz时为-90.72dB。

Design of a High Precision CMOS Bandgap Reference Circuit

By using ASMC 0.35 μm complementary metal-oxide semicondutor(CMOS)model,a high performance bandgap reference circuit was designed,which is with 1 V output voltage,low power consumption,high power supply rejection ratio(PSRR)and low temperature coefficient.The cascode self-biased voltage structure for amplifier was applied,and the output of the operational amplifier(OPAMP)was used as the bias of itself and the next stage.A propertional to absolute temperature(PTAT)temperature compensation was realized.The Cadence Spectre was used for the simulation.The results show that the output voltage temperature coefficient is 3.68×10-6/℃ and the voltage swing is less than 0.094 mV at 1.6-5 V power supply voltage from-40 ℃ to 125 ℃,and the PSRR is-114.6 dB at low frequencies,where-109.3 dB at 1 kHz and-90.72 dB at 10 kHz.