| 摘要 |
PROBLEM TO BE SOLVED: To provide a synchronous delay circuit device which can secure appropriate delay time by means of a precise operation and which is constituted in small scale. SOLUTION: The synchronous delay circuit device is provided with an input buffer 3, a clock driver 4, a dummy delay circuit 5 and delay circuit strings 1 and 2 constituted of the prescribed number of delay circuits having prescribed delay time, a frequency measuring circuit 10 showing a result measuring the frequency of an external clock C1, K1 and outputting a frequency measuring signal and a delay time control circuit 11 controlling prescribed delay time by controlling the travel speed of the pulse or the edge of the delay circuit strings 1 and 2 in accordance with the frequency measuring signal, which has the similar constitution as a former device. The delay time control circuit 11 controls prescribed delay time corresponding to the measuring result of the frequency of the external clock CLK 1 in the delay time control circuit 11. Thus, the clock or the edge is prevented from extending from the delay circuit string 1 at the time of using the low frequency. |
