| 摘要 |
PURPOSE:To facilitate the large scale circuit integration without needing a capacitor group as a control element by connecting a capacitor in parallel with a series circuit of resistor groups selected in response to the changeover of a switch and the switch itself. CONSTITUTION:The switch 101 switched in response to a control signal and a resistor group 102 comprising plural resistors selected in response to the changeover of the switch 101 are connected in series. A capacitor 103 is connected in parallel with the series circuit. The series capacitance of a frequency control element is changed by using the switch to select the resistors and the oscillated frequency of the crystal oscillator is controlled in response thereto.
|
