Patent ID: 7446602

Claim:
A switched capacitor amplifier having an operational amplifier and switched capacitors, for amplifying a differential voltage between voltages inputted to a plus (+) input terminal and a minus (−) input terminal of the operational amplifier while an offset including a noise of the operational amplifier is compensated, and outputting an amplified voltage between a plus (+) output terminal and a minus (−) output terminal, the switched capacitor amplifier comprising: a first switched capacitor one terminal of which is connected with the plus (+) input terminal and an other terminal of which is applied with an input voltage; a second switched capacitor one terminal of which is connected with the minus (−) input terminal and an other terminal of which is applied with an input voltage; a third switched capacitor which is inserted between the plus (+) input terminal and the plus (+) output terminal and provided to set an amplification factor in cooperation with the first switched capacitor and store a plus (+) compensation voltage for compensating for an offset, which is applied to the plus (+) input terminal; and a fourth switched capacitor which is inserted between the minus (−) input terminal and the minus (−) output terminal and provided to set an amplification factor in cooperation with the second switched capacitor and store a minus (−) compensation voltage for compensating for an offset, which is applied to the minus (−) input terminal.