Patent ID: 7932752
Filing Date: 2011-04-26
Classification: H04N

Abstract:
1. A correlated double sampling circuit including a first input terminal, a second input terminal, a first output terminal, a second output terminal, a first feedback capacitor, a second feedback capacitor, a first sampling capacitor, a second sampling capacitor, and an operational amplifier, comprising: the first sampling capacitor divided into a plurality of portions to sample a signal of a feed-through portion input to the first input terminal at a plurality of sampling points, the plurality of portions being connected in parallel with each other; the second sampling capacitor divided into a plurality of portions to sample a signal of a data portion input to the second input terminal at a plurality of sampling points, the plurality of portions being connected in parallel with each other; a plurality of sampling switches respectively connected in series with the plurality of portions of the first sampling capacitor; a plurality of sampling switches respectively connected in series with the plurality of portions of the second sampling capacitor; an averaging switch for calculating a first average value of a plurality of sampling values respectively obtained by sampling by the plurality of portions of the first sampling capacitor, and an averaging switch for calculating a second average value of a plurality of sampling values respectively obtained by sampling by the plurality of portions of the second sampling capacitor, wherein a difference between the first average value and the second average value is amplified using a value determined from a ratio of the first sampling capacitor, the second sampling capacitor, the first feedback capacitor, and the second feedback capacitor.