| 摘要 |
<p>PURPOSE:To shorten the internal clock generation time of a voltage control type oscillator in the case a vibrator restarts oscillation by adding a device which can select and output other output voltage than an output voltage of a low-pass filter as a control voltage of the voltage control type oscillator of an internal clock generating device using a PLL circuit. CONSTITUTION:Between a low-pass filter(LPF) 12 and a voltage control type oscillating circuit(VCO) 13, a selecting device 16 is provided so that a control voltage of the VCO 13 can be selected and switched between an output voltage of a voltage generating device 21 and an output voltage of the LPF 12, and by a selecting device control signal 20, an output voltage of an external voltage generating device 21 is selected, when a vibrator restarts vibration from a vibration stop state.</p> |
