Considerations of a Common-mode Feedback Circuit in the CMOS Inverter-based Differential Amplifier
Details
Push-pull CMOS inverter is effective for high-speed, low-power operations, but it has poor CMRR and PSRR characteristics. Common-mode feedback circuits with transistor-pairs operating triode-region is implemented in the push-pull CMOS pseude-differential amplifier. SPICE simulations indicate improvement of CMRR and PSRR. A single common-mode feedback circuit in the push-pull CMOS differential amplifier is also effective. It suppresses the common-mode offset voltage caused by charge injection of switch transistors in the comparator using push-pull CMOS differential amplifiers.
