摘要
基于SOC应用,采用CSMC 0.5μm DPDM CMOS工艺,设计了一种恒定跨导的Rail-to-Rail CMOS运算放大器。该运算放大器采用平方根电路恒定输入级总跨导;同时运用Class AB推挽电路作输出级,获得高驱动能力和低谐波失真。在5 V单电源工作电压、30 pF负载电容和10 KΩ负载电阻情况下,经过Hspice仿真,运放的直流开环增益达到98 dB,相位裕度为65°,输入级跨导最大偏差低于17%。
Based on SOC application, a Rail-to-Rail CMOS operational amplifier core with constant transconductance is presented. The operational amplifier will be realized in the CSMC 0. 5 μm DPDM CMOS process. The op amp applies square-root circuit to keep the total transconductor of the input stage constant. Meanwhile, a class AB output stage is also developed to ensure large dynamic range, strong driving capability and low harmonic distortion. With a single power supply of 5 V and 30 pF load-capacitance, 10 kΩ-load resistance in simulation, the whole circuit is simulated by Hspice, it is shown that the Rail to Rail operational amplifier has an open loop gain of 98 dB, a unit gain frequency of 6 MHz, a phase margin of 65 degree and a low transconductor deviation of 17% .
出处
《电子器件》
EI
CAS
2006年第3期710-713,717,共5页
Chinese Journal of Electron Devices