| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a delay control circuit which delays a strobe signal by using a variable delay circuit including a plurality of unit delay elements and which performs an operation test of all the unit delay elements in a short time, not depending on the nonuniformity in the unit delay time of each chip. Ž<P>SOLUTION: The delay control circuit 1 includes a reference variable delay circuit 3 which delays a reference clock signal, a strobe variable delay circuit 17 which delays the strobe signal, and the delay control circuit 9 for testing which sets a delay time for testing on the variable delay circuits 3 and 17 having the same constitution. On the occasion of testing the two variable delay circuits 3 and 17, the delay time for testing is set on the circuits 3 and 17 and the reference clock signal delayed through the reference variable delay circuit 3 is input to the strobe variable delay circuit 17. On the occasion of testing, besides, the delay control circuit 9 for testing increases the delay time for testing for one side and decreases it for the other, while the total delay time is left fixed. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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