| 摘要 |
<p>PURPOSE:To execute the quick operation of a microcomputer without giving the influence of the higher harmonics of an oscillation clock to a microcomputer peripheral integrated circuit by generating the operation clock of a high frequency based on the oscillation clock of a low frequency generated by an oscillator. CONSTITUTION:This circuit is provided with the oscillator 1 generating the oscillation clock of a prescribed frequency, an integrator 22 executing charge and discharge, a voltage control oscillator 23 generating the oscillation clock corresponding to this charge and discharge, a frequency divider 24 frequency- dividing the oscillation clock of the voltage control oscillator 23, a phase comparator 9 generating a correction signal so as to synchronize the oscillation clock and the frequency dividing clock by the shifting time of the oscillation clock of the oscillator 1 and the frequency dividing clock of the frequency divider 24, and control circuits 17 and 18 controlling the charge and discharge of the integrator 22 in accordance with the correction signal of the phase comparator 9. Then, the voltage control oscillator 23 generates the multiplying clock of the oscillation clock of the oscillator 1 so as to use it as the operation clock of the microcomputer.</p> |
