PURPOSE: To simply obtain standardized pulses in the range of a low level to a high level equal to the power source voltage by a method wherein CCD drive system is composed of a plurality of MOSFETs and a capacitor, and the β-ratio of a driver FET to a load FET is set at a value of one figure optionally selected.

CONSTITUTION: The driver system at the final step which produces pulse ID to feed it to CCD consist of MOSFET element M1∼M3, and of capacitors C2 and CI. With the constructed driver system, there applies a pulse of counter phase to a gate In2 of element M3, while applying pulse ID or TTL or MOS level to a capacitor C2, and makes these pulse standardized ones ranging from a low level of voltage to a high level voltage through a boolstrap circuit consisting of element M1∼M3 and boots capacity C2. Accordingly, it can facilitate the level changeable by setting a value smaller by one figure than a value which is decided in a normal logic circuit for channel width/channel length of element M3 as against the element M2.