摘要 |
A DLL circuit includes a counter control circuit. The counter control circuit includes an inverter, a NAND gate, a shift register, a clocked inverter, and a NOR gate. When a reset signal RST of an H level, or a smallest address signal CMIN indicating the smallest value of the address is input, the counter control circuit forces a signal REV to be switched to an H level and generates a counter control signal ADD and a signal EN of an H level, whereby the counter enters a force up mode. As a result, the delay clock CLKD can be set in phase with a reference clock CLK stably.
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