| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a clock generation method and a clock generation circuit, wherein uniform spectrum spread is effectively achieved with simple configuration. <P>SOLUTION: When a PLL circuit and a modulator are used and a frequency division ratio of a frequency divider for feedback in the PLL circuit is changed in accordance with modulation data generated on the basis of a modulation profile of the modulator, to perform spectrum spread by frequency modulation, a turnaround point of the modulation profile is moved to distribute frequency frequencies and the spread spectrum is spread again. The clock generation circuit comprises the PLL circuit and the modulator, and the modulator is provided with a multiple modulation profile generation circuit, and the turnaround point of the modulation profile is moved to distribute frequency frequencies, whereby the spread spectrum is spread again. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
