A 100 MHz 100 dB operational amplifier with multipath nested Miller compensation structure

A multipath nested structure which overcomes the bandwidth reduction in the conventional nested structure by appending an independent feedforward path for high frequencies is presented. At low frequencies, the opamp behaves as a three-stage nested Miller-compensated amplifier, while at high frequencies the opamp has the nature and bandwidth of a two-stage amplifier with simple pole splitting. In this fashion, the concept circumvents the classical DC-gain/high-frequency-performance dilemma. No pole-zero doubles occur, because the two regions of operation can be independently and closely matched, unaffected by variations in the parameters of the IC process in which the amplifier is fabricated.<>