| 摘要 |
PURPOSE:To erase the stationary voltage deviation emerging among the output terminals of each detecting means, by applying the controllable compensating voltage to one side of the positive and negative signal charge detecting means synchronously with the timing of transfer. CONSTITUTION:The voltage variable circuit 10 is provided at the side of the charge amplifier CA<-> that functions as a signal charge detecting means of one side. The circuit 10 is formed into a source follower amplifier with the insulated gate field effect transistor (IGFET)QA functioning as an amplifying active element and the IGFET QL functioning as a negative active element. The gain of the means 10 can be controlled by the voltage variable control voltage VB which is applied to the gate of IGFETQL. Thus the 2nd phase transfer voltage phi2 to be applied to the gate of IGFETQA is applied to the input terminal of the charge amplifier CA<-> for negative signal charge detection via the coupling capacity CC and after the level is varied to a proper value. |
