Power supply rejection ratio in operational transconductance amplifiers

The power supply rejection ratio (PSRR) of operational amplifiers is analyzed. An analyzing technique based on cuts in subcircuits is presented. The technique allows hand calculation of the PSRR of any circuit. It is shown that the PSRR of the single-stage operational amplifier (OTA) is one order of magnitude better than the commonly used Miller OTA. The analyses are compared with hand calculations and SPICE level-2 simulations on a realized improved Miller OTA structure. >