PURPOSE: To simplify the constitution by providing a couple of voltage holding means holding voltage of each capacitor and a couple of switch means connected between input and output of the voltage holding means corresponding to each capacitor so as to decrease the number of switches controlling the inversion of charge transfer.

CONSTITUTION: The voltage holding circuits 3, 4 are provided to the charge recombination type A/D converter so as to hold the voltage stored in capacitors C1, C2 by on/off control of switches S1∼S3 applied to an operational amplifier 1. Further, switches S4, S5 are provided between the input and output of the holding circuits 3, 4 so as to process the charge in the capacitors C1, C2 by the operational amplifier 1 and a comparator 2. Moreover, one charge in the capacitors C1, C2 is applied respectively as a reference voltage to the comparator 2, where the voltage is compared with an analog input voltage Vs, and the number of switches whether or not inverting the transfer of charge is decreased so as to attain ease of control.