SEMICONDUCTOR DIFFERENTIAL AMPLIFIER HAVING FEEDBACK BIAS CONTROL FOR STABILIZATION

摘要

Tsi?idis-1 16. SEMICONDUCTOR DIFFERENTIAL AMPLIFIER HAVING FEEDBACK BIAS CONTROL FOR STABILIZATION An MOS differential amplifier includes a pair of substantially identical branches, each branch having a signal input MOS transistor feeding a separate MOS load transistor. Both branches are supplied current by a single current-source MOS transistor. In order to stabilize the(source-to-drain) bias voltages of the signal input and load transistors against fluctuations caused by semiconductor wafer-to-wafer processing variations, an auxiliary amplifier branch is added (for sensing the bias voltage) together with a feedback loop to the currentsource (for controlling the current in response to the sensing of the bias voltage).