| 摘要 |
PROBLEM TO BE SOLVED: To provide a read circuit wherein an output value after subtraction is not affected by the offset voltage of an operational amplifier that reads a signal from sample-and-hold capacitors, even if a read gain is set equal with or less than 1 in a circuit that determines a difference between signals held by two sample-and-hold capacitors. SOLUTION: In two operational amplifiers provided for reading signals held in two sample-and-hold capacitors, each of the operational amplifiers samples an offset voltage of the other in reset operation and, in addition, also samples its own offset voltage and the signal read circuit includes a means for reading the sampled offset voltage and adding the offset voltage to an output of each of the operational amplifiers in read operation. COPYRIGHT: (C)2007,JPO&INPIT
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