| 摘要 |
PROBLEM TO BE SOLVED: To obtain a CV conversion circuit for differential type switched capacitor for converting a substantial capacitive difference (signal factor) of two sensor capacitors to a voltage signal with high gain by a first stage operational amplifier even for a differential electrostatic capacitor type sensor with large offset capacity. SOLUTION: In operation of the electron charge transfer, first and second charged sensor capacitors Csa, Csb, and a correction capacitor Coa are separated from a charging voltage source±Vd and a correction voltage source±Voc, and the first and second sensor capacitors Csa, Csb and the correction capacitor Coa are connected with an inverting input terminal of an operational amplifier 1. Then, a charged electron charge, in which the first and second sensor capacitors Csa, Csb, and the correction capacitor Coa are added, is transferred to a feed-back capacitor Ccv and a voltage proportional to the added charged electron charge is generated at an output of the operational amplifier 1. COPYRIGHT: (C)2007,JPO&INPIT
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