SIGNAL PROCESSING CIRCUIT OF CHARGE GENERATION TYPE DETECTION ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide a signal procesing circuit of charge generation type detection element capable of reducing the direct current offset error of power voltage and reducing high frequency noise against the power voltage. SOLUTION: A signal processing circuit 1 of a charge generation type detection element 109 is provided with a charge-voltage conversion circuit 100 for converting the charge generated in the charge generation type detection element 109 to voltage. The charge-voltage conversion circuit 100 includes a capacitor 111 accumulating the charge generated in the charge generation type detection element 109, an operation amplifier 110 feedback-connected to the capacitor 111, and a switch 107 connected in parallel to the capacitor 111 and discharging the charge accumulated in the capacitor 111. The switch 107 includes a first transistor 101 generating a first clock feed-through and a second transistor 102 generating a second clock feed-through. The switch 107 is so constituted that at least a part of the first clock feed-through is cancelled by the second clock feed-through.