| 摘要 |
PROBLEM TO BE SOLVED: To provide a technology of canceling an offset of an input signal applied to a correlated double sampling circuit. SOLUTION: The correlated double sampling circuit includes: an amplifier 16 with an input and an output; an input terminal receiving the input signal; an input capacitor 11 connected to the input terminal for first and second time phases; a feedback capacitor 18 connected to the output of the amplifier at the second time phase; a capacitor 15 connected between the amplifier input and a node for connection to the input capacitor and the feedback capacitor and for maintaining an offset cancel level for the second time phase; and a means for giving a first reference level to the capacitor maintaining the offset cancel level for the first time phase, and even when a circuit gain is varied, the correlated double sampling circuit cancels the offset of the input signal by applying the reference level to the capacitor maintaining the offset cancel level and varying the reference level with the circuit gain. COPYRIGHT: (C)2007,JPO&INPIT
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