高电源电压抑制比基准电压源的设计

在此通过对带隙基准电压源电路进行建模分析,针对逆变电路的中低频使用环境,设计了一个应用于高压逆变器电路中的高电源电压抑制比,低温度系数的带隙基准电压源。该电路采用1μm,700 V高压CMOS工艺,在5 V供电电压的基础上,采用一阶温度补偿,并通过设计高开环增益共源共栅两级放大器来提高电源电压抑制比,同时使用宽幅镜像电流偏置解决因共源共栅引起的输出摆幅变小的问题。基准电压源正常输出电压为2.394 V,温度系数为8 ppm/℃,中低频电压抑制比均可达到-112 dB。

Design of reference voltage source with high power supply rejection ratio

Based on modeling and analysis of the bandgap reference voltage source circuit,a bandgap reference voltagesource with high power supply rejection ratio and low temperature coefficient was designed for high-voltage low-frequency invertercircuit. CMOS process of 1 μm and 700 V high-voltage is used in this circuit,which adopts first-order temperature compensa-tion at 5 V voltage. A cascode two-stage amplifier with high open-loop gain was designed to improve the power supply rejectionratio. The wide mirror current bias circuit is used to solve the problem that the output swing becomes smaller due to the cascodecircuit. The normal output voltage of the reference voltage source is 2.394 V,its temperature coefficient is 8 ppm/℃,and its low-medium frequency voltage rejection ratio can reach -112 dB.