Patent ID: 7619445

Claim:
A differential amplifier circuit comprising: an input differential stage including a first differential pair, second differential pair, and at least one load circuit connected to output pairs of said first and second differential pairs; and an amplifier stage, receiving a common output signal of said first and second differential pairs, for charging or discharging an output terminal; wherein a preset reference voltage is supplied to one of the differential inputs of said first differential pair; and wherein said differential amplifier circuit further comprises a control circuit for controlling the switching between a first state in which said output terminal is connected in a feedback fashion to the other of differential inputs of said first differential pair, the voltage at said output terminal is stored in a capacitor connected to the other of the differential inputs of said first differential pair, and first and second voltages are respectively supplied to differential inputs of said second differential pair, and a second state in which said output terminal is connected in a feedback fashion to one of differential inputs of said second differential pair, a third voltage is applied to the other of the differential inputs of said second differential pair, and the other of the differential inputs of said first differential pair is disconnected from said output terminal.