| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a clock generation circuit capable of making a lock-up time short. <P>SOLUTION: The clock generation circuit 1 comprises: a spread spectrum clock generation circuit 10 generating a modulation clock SCLK with a frequency modulated based on a reference clock RCLK; and a phase comparator 20 that outputs a H level lock signal LOCK when detecting phase coincidence between the reference clock RCLK and the modulation clock SCLK. Moreover, the clock generation circuit 1 comprises a selector 50 that selects the reference clock RCLK as an output clock CLK until the H level lock signal LOCK is output, and selects the modulation clock SCLK in response to the output of the H level lock signal. <P>COPYRIGHT: (C)2012,JPO&INPIT |
