一种带共模反馈电路的套筒式全差分运算放大器  

A Telescopic Fully Differential Amplifier with CMFB Circuit

作　　者：成东波[1] 孙玲玲[1] 洪慧[1] 章少杰[1] 吴国峰[1] 

机构地区：[1]杭州电子科技大学射频电路与系统教育部重点实验室,杭州310018

出　　处：《微电子学》2011年第3期336-340,共5页Microelectronics

基　　金：浙江省自然科学基金资助项目(Y1090877);长三角科技合作项目资助(2008C16017)

摘　　要：基于Chartered 0.35μm工艺,设计了一种带共模反馈电路的套筒式全差分运算放大器。该电路主要由套筒式结构的主运放、偏置电路和共模反馈电路组成。仿真结果表明,设计的电路开环增益为79.4 dB,单位增益带宽为179 MHz,相位裕度为75.5°(负载Cload=3 pF),功耗为2.31 mW。提出了一种全新的全差分运放增益测试方法,可以比较准确地测得运放的低频增益。对通过流片的电路进行测试和分析,结果与仿真指标基本接近,达到预先设计的要求。Based on Chartered 0.35 μm process,a telescopic fully differential amplifier with CMFB circuit was designed.The circuit was composed of a telescopic amplifier,a biasing circuit and a CMFB circuit.Simulation results showed that the amplifier had an open-loop gain of 79.4 dB,a unity-gain bandwidth of 179 MHz,and a phase margin of 75.5° at a capacitive load of 3 pF,and it dissipated a power of 2.31 mW.Moreover,a new open-loop gain test circuit was proposed to accurately test low frequency gain of the fully differential operational amplifier.Finally,the tape-out amplifier was tested and analyzed,and results indicated that the proposed amplifier achieved its design goal in general.

关 键 词：套筒式结构 运算放大器 共模反馈电路 

分 类 号：TN492[电子电信—微电子学与固体电子学]