SYNCHRONIZING METHOD FOR DELAY SYNCHRONIZING LOOP, DELAY SYNCHRONIZING LOOP, AND SEMICONDUCTOR DEVICE PROVIDED WITH THE DELAY SYNCHRONIZING LOOP

摘要

PROBLEM TO BE SOLVED: To perform accurate delay synchronizing operation with low power consumption. SOLUTION: In a synchronizing method for a delay synchronizing loop, a phase of an external clock ECK is made coincident with an external clock with a phase of dummy data DDT outputted to the outside synchronizing with an internal clock ICK in which the external clock ECK is delayed by the prescribed delay time by chancing a delay time, delay synchronizing operation generating the internal clock ICK synchronizing with the external clock ECK is performed only when a delay synchronizing command DLC indicating start of delay synchronizing operation is supplied from a CPU not shown in a figure, when the synchronizing command DLC is not supplied, a delay time changed by the time is held.