Timing control circuit and semiconductor storage device

Abstract

Disclosed is a timing control circuit which receives a first clock having a period Tand a group of second clocks of L different phases (where L is a positive integer) spaced apart from each other at substantially equal intervals and which generates a fine timing signal delayed from the rising edge of the first clock by a delay td of approximately td=m·T+n·(T/L), where m and n are non-negative integers. The timing control circuit has a coarse delay circuit and a fine delay circuit. The coarse delay circuit counts the rising edges of the first clock after an activate signal is activated and generates a coarse timing signal delayed from the first clock by approximately m·T. The fine delay circuit has a circuit which, after the activate signal is activated, detects a second clock, which has a rising edge that immediately follows the rising edge of the first clock, from among the group of L-phase second clocks. Using the edge-detection information, the fine delay circuit generates a fine timing signal for which the amount of delay from the coarse timing signal is approximately n·(T/L). The values of m and n can be set by registers.