一种恒跨导高增益轨到轨运算放大器
|
摘要
基于TSMC 0.18μm CMOS工艺,设计了一种新颖的恒跨导高增益轨到轨运算放大器。输入级仅由NMOS管差分对构成,采用电平移位及两路复用选择器控制技术,在轨到轨共模输入范围内实现了输入级恒跨导。中间级采用折叠式共源共栅放大器结构,运算放大器能获得高增益。输出级采用前馈型AB类推挽放大器,实现轨到轨全摆幅输出。利用密勒补偿技术进行频率补偿,运算放大器工作稳定。仿真结果表明,在1.8V电源电压下,该运算放大器的直流开环增益为129.3dB,单位增益带宽为7.22MHz,相位裕度为60.1°,整个轨到轨共模输入范围内跨导的变化率为1.44%。
A novel high gain rail-to-rail operational amplifier circuit was designed in TSMC 0.18μm CMOS process.The input stage of the circuit was composed of only NMOS differential pairs.The level shift circuit and the two channel multiplexers were used to keep the input stage constant-gmin the rail-to-rail common mode range.A folded cascode amplifier architecture was used in the intermediate stage of the amplifier to ensure that the operational amplifier could achieve high gain.The rail-to-rail output was achieved by the feedforward class AB pushpull amplifier in the output stage.The Miller compensation was used to ensure that the operational amplifier could operate in a stable state.Simulation results showed that the DC open loop gain of the operational amplifier was 129.3 dB when the amplifier operated at 1.8 V power supply voltage,the unit gain bandwidth was 7.22 MHz,the phase margin was 60.1°,and the overall transconductance variation was only 1.44% over the rail-to-rail common mode input range.
A novel high gain rail-to-rail operational amplifier circuit was designed in TSMC 0.18μm CMOS process.The input stage of the circuit was composed of only NMOS differential pairs.The level shift circuit and the two channel multiplexers were used to keep the input stage constant-gmin the rail-to-rail common mode range.A folded cascode amplifier architecture was used in the intermediate stage of the amplifier to ensure that the operational amplifier could achieve high gain.The rail-to-rail output was achieved by the feedforward class AB pushpull amplifier in the output stage.The Miller compensation was used to ensure that the operational amplifier could operate in a stable state.Simulation results showed that the DC open loop gain of the operational amplifier was 129.3 dB when the amplifier operated at 1.8 V power supply voltage,the unit gain bandwidth was 7.22 MHz,the phase margin was 60.1°,and the overall transconductance variation was only 1.44% over the rail-to-rail common mode input range.
引文
[1]赵双,刘云涛.恒跨导轨对轨CMOS运算放大器的设[J].微电子学,2016,46(3):302-305,310.
[2]HOGERVORST R,TERO J P,ESCHAUZIER R G H,et al.A compact power-efficient 3VCMOS rail-torail input/output operational amplifier for VLSI cell libraries[J].IEEE J Sol Sta Circ,1994.29(12):1505-1513.
[3]齐步坤.轨到轨CMOS运算放大器研究与设计[D].天津:天津大学,2009.
[4]LEE B,HIGMAN T.1.2 V constant-gm rail-to-rail CMOS op-amp input stage with new overlapped transition regions technique for ECG amplifier[C]//35th Annu Int Conf EMBC.Osaka,Japan.2013:3451-3454.
[5]傅锐飞.一种低压功耗CMOS轨对轨运算放大器的设计[D].成都:电子科技大学,2009.
[6]DUBEY A K,NAGARIA R K,PAL P K,et al.Enhanced slew rate,constant-gm rail-to-rail opamp using 1:2current mirror biasing technique[C]//Int Conf Comput,Commun&Autom.Noida,India.2017:1612-1618.
[7]马玉杰,高俊丽,后永奇,等.3.3V/0.18μm恒跨导轨对轨CMOS运算放大器的设计[J].电子技术应用,2012,38(11):48-50,54.
[8]李有慧.一种输入输出轨到轨CMOS运算放大器的设计[J].电子科技,2015,28(6):165-169.
[9]王丹,姜宇,郭桂良,等.一种低压高性能的Rail-toRail运算放大器[J].微电子学与计算机,2017,34(2):68-72.
[2]HOGERVORST R,TERO J P,ESCHAUZIER R G H,et al.A compact power-efficient 3VCMOS rail-torail input/output operational amplifier for VLSI cell libraries[J].IEEE J Sol Sta Circ,1994.29(12):1505-1513.
[3]齐步坤.轨到轨CMOS运算放大器研究与设计[D].天津:天津大学,2009.
[4]LEE B,HIGMAN T.1.2 V constant-gm rail-to-rail CMOS op-amp input stage with new overlapped transition regions technique for ECG amplifier[C]//35th Annu Int Conf EMBC.Osaka,Japan.2013:3451-3454.
[5]傅锐飞.一种低压功耗CMOS轨对轨运算放大器的设计[D].成都:电子科技大学,2009.
[6]DUBEY A K,NAGARIA R K,PAL P K,et al.Enhanced slew rate,constant-gm rail-to-rail opamp using 1:2current mirror biasing technique[C]//Int Conf Comput,Commun&Autom.Noida,India.2017:1612-1618.
[7]马玉杰,高俊丽,后永奇,等.3.3V/0.18μm恒跨导轨对轨CMOS运算放大器的设计[J].电子技术应用,2012,38(11):48-50,54.
[8]李有慧.一种输入输出轨到轨CMOS运算放大器的设计[J].电子科技,2015,28(6):165-169.
[9]王丹,姜宇,郭桂良,等.一种低压高性能的Rail-toRail运算放大器[J].微电子学与计算机,2017,34(2):68-72.