摘要 |
In a feedback amplifier circuit, a first switching device executes an auto-zero operation by inputting a signal outputted from an amplifier to an input terminal of the amplifier during an auto-zero operation interval prior to an amplification interval. A first capacitor accumulates and holds an offset voltage at the output terminal of the amplifier during the auto-zero operation interval, and cancels an offset voltage at the input terminal of the amplifier by an accumulated and held offset voltage during an amplification interval subsequent to the auto-zero operation interval. A second switching device grounds the feedback point of the feedback circuit during the auto-zero operation interval. A second capacitor blocks a DC voltage, and accumulates and holds an offset voltage at an output terminal of the amplifier, and cancels an offset voltage at an input terminal of the amplifier by the accumulated and held offset voltage during an amplification interval. |