一种高电源抑制比带隙基准电压源的设计

设计了一种基于反馈电路的基准电压电路。通过正、负两路反馈使输出基准电压获得了高交流电源抑制比(PSRR),为后续电路提供了稳定的电压。采用NPN型三极管,有效消除了运放失调电压对带隙基准电压精度产生的影响,并对电路进行温度补偿,大大减小了温漂。整个电路采用0.35μm CMOS工艺实现,通过spectre仿真软件在室温27℃、工作电压为4 V的条件下进行仿真,带隙基准的输出电压为1.28 V,静态电流为2μA,在-20~80℃范围内其温度系数约为18.9×10-6/℃,交流PSRR约为-107 dB。

Design of a High Power Supply Rejection Ratio Bandgap Reference Voltage

A reference voltage circuit based on feedback circuit is designed. Through the positive and negative feedback, the output reference voltage can obtain a high AC power supply rejection ratio(PSRR), which provides a stable voltage for the follow-up circuit. NPN triode is used to eliminate the influence of op amp offset voltage on the accuracy of bandgap reference voltage, and to compensate the circuit temperature, which greatly reduces the temperature drift. The whole circuit is realized by 0.35 μm CMOS process. The simulation is carried out by spectre simulation software at room temperature of 27 ℃ and working voltage of 4 V. The output voltage of bandgap reference is 1.28 V, the static current is 2 μA, the temperature coefficient is about 18.9×10-6/℃, and the AC PSRR is about –107 dB in the temperature range of –20-80 ℃. The reference voltage source has the advantages of simple structure, low power consumption and high power rejection ratio.