【摘要】 设计了一个1.5 V低功耗轨至轨CMOS运算放大器。电路设计中为了使输入共模电压范围达到轨至轨性能,采用了NMOS管和PMOS管并联的互补差动对输入结构,并采用成比例的电流镜技术实现了输入级跨导的恒定。在中间增益级设计中,采用了适合在低压工作的低压宽摆幅共源共栅结构;在输出级设计时,为了提高效率,采用了简单的推挽共源级放大器作为输出级,使得输出电压摆幅基本上达到了轨至轨。当接100 pF电容负载和1 kΩ电阻负载时,运放的静态功耗只有290μW,直流开环增益约为76 dB,相位裕度约为69°,单位增益带宽约为1 MHz。更多还原

【Abstract】 A 1.5 V low power rail-to-rail CMOS operational amplifier was designed.In order to enable the input common mode voltage range to achieve rail-to-rail,the NMOS tube and the PMOS tube parallel supplementary differential input pair was used in circuit structure,and proportional current mirror technology was adopted to realize the constant trans-conductance of input stage.In the middle gain stage design,the low voltage,wide-swing cascode structure was adopted,which was suitable to work in low voltage.In the output stage,the push-pull common source stage amplifier was used to improve efficiency,output voltage swing basically reached rail-to-rail.The results show that it has only 290 μW static power,76 dB DC open-loop gain,1 MHz unity-gain bandwidth and 69° phase margin with 100 pF load capacitance and 1 kΩ load resistance.更多还原