华中科技大学学报（自然科学版）2011，Vol.39Issue(1)：19-23,5.
前馈型轨到轨恒跨导恒增益CMOS运算放大器
Feedforward rail to rail constant-gm constant gain CMOS operational amplifiers
摘要
Abstract
A rail-to-rail operational amplifier(OPA) with constant transconductance(gm) and constant gain was introduced. The input stage was a complementary differential pair controlled by the unity current mirror to realize rail-to-rail common-mode input and constant gm. Based on the relationship between the voltage gain and the common mode level, a novel feedforward constant gain control block was presented, turning on or off an additional current source to maintain the voltage gain unchanged.The feedforward class-AB structure was adopted in the output stage of the OPA to ensure rail-to-rail output. Sample chips were taped out with Chartered 0. 35 μm process. The simulation and test results indicate that the low-frequency gain and unity-gain bandwidth of the proposed OPA circuit were 125dB and 8. 879 MHz respectively, and the voltage gain changes only about 1.69％ over the commonmode input range.关键词
运算放大器/前馈控制/恒增益/恒跨导/轨到轨Key words
operational amplifier/ forward control/ constant transconductance/ constant gain/ rail-to-rail分类
信息技术与安全科学引用本文复制引用
张为,彭彦豪,齐步坤,姜宇..前馈型轨到轨恒跨导恒增益CMOS运算放大器[J].华中科技大学学报（自然科学版）,2011,39(1):19-23,5.基金项目
天津市科技支撑计划重点资助项目(10ZCKFGX3600) （10ZCKFGX3600）
天津大学自主创新基金资助项目. （）
