PURPOSE: To speed up the operation of the circuit and to reduce energy consumption by replacing a D-latch, which does not require a reset means, with a D-latch having two-input OR function.

CONSTITUTION: Since the inverted output of a D-latch 14 is turned to a high level in a reset state, an input to a D-latch 11 is set at the high level even when the output of a D-latch 16 is in any state, and since there is no influence upon operations, the reset means is not required for the slave latch of a flip-flop circuit in the final step. Then, the function of a multiple input OR circuit is allocated again to a transistor allocated to the reset means of this slave latch, and the two-input OR circuit is taken into the D-latch without increasing the number of serially connected gate logic stages. Thus, an area to be occupied by the circuit can be reduced, and current consumption can be lowered.