CMRR-bandwidth extension technique for CMOS differential amplifiers

An exemplary design demonstrates how to extend the Common-Mode-Rejection-Ratio (CMRR) bandwidth of a CMOS differential amplifier. The design presented uses MOSFETs with a channel length of 180 nm. A novel circuit technique is employed that partially compensates for the output capacitance of the tail current sink, thereby more than quadrupling the CMRR bandwidth in the example considered.