给出了两种应用于两级CMOS运算放大器的密勒补偿技术的比较,用共源共栅密勒补偿技术设计出的CMOS运放与直接密勒补偿相比,具有更大的单位增益带宽、更大的摆率和更小的信号建立时间等优点,还可以在达到相同补偿效果的情况下极大地减小版图尺寸.通过电路级小信号等效电路的分析和仿真,对两种补偿技术进行比较,结果验证了共源共栅密勒补偿技术相对于直接密勒补偿技术的优越性.
The differences between two methods of Miller compensation in CMOS operational amplifier (opamp) with the structure of folded-cascode are discussed here. Compared with Miller compensation opamp, the cascoded-Miller compensation amplifier can obtain greater gain bandwidth product (GB) and slew rate (SR), the setting time can also be made shorter, the area of the whole circuit can be decreased by reducing the value of the capacitor for compensation without depressing performance. The advantages of cascoded-Miller compensation technology over Miller compensation are represented through the analysis and simulation of the equivalent circuits.