| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem of a variable modulation degree. <P>SOLUTION: A spread spectrum clock generation circuit for generating a spread spectrum signal comprises; a PLL circuit for outputting a frequency-modulated output oscillating signal, which has an oscillation circuit to output the output oscillating signal at a frequency corresponding to the value of an input oscillation control signal; and a frequency modulation unit for generating the oscillation control signal to modulate the frequency of a PLL signal fed back from the PLL circuit, monitoring a maximum value and a minimum value of the oscillation control signal, adjusting the maximum value and the minimum value of the oscillation control signal according to the monitoring result, and controlling the modulation degree of the output oscillation signal to a predetermined value. <P>COPYRIGHT: (C)2012,JPO&INPIT |
