Patent ID: 9148600
Filing Date: 2015-09-29
Classification: H03G,H04N

Abstract:
1. A programmable gain amplifier, comprising: a sampling circuit configured to perform correlated double sampling on an input signal using a reference voltage; a source follower; a first capacitor connected between the sampling circuit and the source follower; and an error amplifier connected between an input terminal of the source follower and an output terminal of the source follower, the error amplifier being configured to reset a voltage of the output terminal of the source follower to the reference voltage during a source follower reset operation that resets the source follower, wherein, the error amplifier includes a plurality of switches, a second capacitor, and an amplifier configured to amplify a difference between the reference voltage and an output voltage of the second capacitor, the switches are arranged to store an offset of the amplifier in the second capacitor during an error amplifier reset operation that resets the error amplifier, and the switches are arranged to reset the voltage of the output terminal of the source follower to the reference voltage and reset the voltage of the input terminal of the source follower to the input voltage during the source follower reset operation.