一款高性能共源共栅运算放大器设计

摘要

基于CSMC O.5μm标准CMOS工艺,采用复用型折叠式共源共栅结构,设计一种折叠式共源共栅运算放大器.该电路在5V电源电压下驱动5 pF负载电容,采用Cadence公司的模拟仿真工具Spectre对电路进行仿真.结果表明,电路开环增益达到了71.7 dB,单位增益带宽为52.79 MHz,开环相位裕度为60.45°.%The folded-cascode operational amplifier has the characteristics of high gain and large bandwidth. Such amplifiers are widely used in integrated circuits for radio communication. The recycling folded cascode structure based on CMOS process with CSMC 0. 5μm standard was adopted to design a folded-cascode operational amplifier and its performance parameters. The 5 pF load capacitance of the amplifying circuit is driven by 5 V power supply. The simulation tool Spectre made by Cadence was employed for the circuit simulation. The simulation result shows that the open loop gain of the circuit is up to 71. 7 dB, the unity gain bandwidth is 52. 79 MHz and the phase margin is 60.45°.