| 摘要 |
PURPOSE:To correct the distortion of a signal waveform due to leakage current by providing a charge integration type operational amplifier circuit having the same characteristic as that of a charge integration type operational amplifier reading out the signal charge, and extracting the difference of the outputs of both the operation amplifiers. CONSTITUTION:The operational amplifier circuit 1 where a signal charge storage capacitor and a reset MOSFET are connected in parallel between the input and output of an operational amplifier is provided, a charge of a sensor section 4 of a solid-state image pickup device is detected and outputted via an inverse amplifier 6. The operational amplifier circuit 7 having the same constitution as the operational amplifier circuit 1 is provided, its input is grounded via a dummy capacitor 10, and an inverse amplifier 8 is provided at the output side. In extracting the difference of outputs of both the inverse amplifiers 6, 8 by a differential amplifier 9; the fluctuation at zero level due to the leakage current of the reset MOSFET of the operational amplifier circuit is compensated and the distortion is reduced. |
