A novel low-voltage operational amplifier for low-power pipelined ADCs  

作　　者：范明俊 任俊彦 过瑶 李宁 叶凡 李联 

机构地区：[1]State Key Laboratory of ASIC & System, Fudan University [2]Micro-Nanoelectronics Science and Technology Innovation Platform, Fudan University

出　　处：《Journal of Semiconductors》2009年第1期82-85,共4页半导体学报（英文版）

摘　　要：A novel low-voltage two-stage operational amplifier employing class-AB architecture is presented. The structure utilizes level-shifters and current mirrors to create the class-AB behavior in the first and second stages. With this structure, the transconductances of the two stages are double compared with the normal configuration without class-AB behaviors with the same current consumption. Thus power can be saved and the operation frequency can be increased. The nested cascode miller compensation and symmetric common-mode feedback circuits are used for large unit-gain bandwidth, good phase margin and stability. Simulation results show that the sample-and-hold of the 12-bit 40-Ms/s pipelined ADC using the proposed amplifier consumes only 5.8 mW from 1.2 V power supply with signal-to-noise-and-distortion ratio 89.5 dB, spurious-free dynamic range 95.7 dB and total harmonic distortion -94.3 dB with Nyquist input signal frequency.A novel low-voltage two-stage operational amplifier employing class-AB architecture is presented. The structure utilizes level-shifters and current mirrors to create the class-AB behavior in the first and second stages. With this structure, the transconductances of the two stages are double compared with the normal configuration without class-AB behaviors with the same current consumption. Thus power can be saved and the operation frequency can be increased. The nested cascode miller compensation and symmetric common-mode feedback circuits are used for large unit-gain bandwidth, good phase margin and stability. Simulation results show that the sample-and-hold of the 12-bit 40-Ms/s pipelined ADC using the proposed amplifier consumes only 5.8 mW from 1.2 V power supply with signal-to-noise-and-distortion ratio 89.5 dB, spurious-free dynamic range 95.7 dB and total harmonic distortion -94.3 dB with Nyquist input signal frequency.

关 键 词：low-voltage operational amplifier CLASS-AB two-stage amplifier low-power pipelined ADC 

分 类 号：TN722[电子电信—电路与系统] TM933[电气工程—电力电子与电力传动]