| 摘要 |
PROBLEM TO BE SOLVED: To accurately adjust a delay amount of a strobe signal relatively to a wide frequency range and to execute a setup margin test.SOLUTION: An interface circuit 5 that is provided in a semiconductor device 1 includes a delay circuit 25 for delaying a strobe signal DQS received from an external memory device 2. The delay circuit 25 includes a first adjustment circuit 26 for rough adjustment including a plurality of delay elements DE and a second adjustment circuit 27 for precise adjustment. The first adjustment circuit 26 includes: a bypass line which is connected in parallel with a part of the plurality of delay elements DE and has a delay amount smaller than a delay amount of the entire partial delay elements connected in parallel; and selectors 54-57 for selecting and outputting the strobe signal DQS that passes a part of the plurality of delay elements DE, or the strobe signal DQS that passes the bypass line connected in parallel.SELECTED DRAWING: Figure 19 |
