| 摘要 |
PURPOSE: A voltage control oscillator having a triple band function is provided to perform a mobile communication function of all frequency bands in cellular phones using different frequency bands such as GSM, DCS, and PCS. CONSTITUTION: A PLL(Phase Locked Loop) module is formed with an oscillation portion for generating a frequency signal of a specific frequency band, a voltage control oscillator of generating a frequency corresponding to intensity of input voltage, and a PLL for receiving the frequency signal of the oscillation portion and the frequency of the voltage control oscillator and changing the intensity of the voltage. The voltage control oscillator is formed with a band switching portion, the first VCO band, the second VCO band, and a resonant frequency switching portion. The band switching portion changes a transfer path of driving power to the first output terminal or the second output terminal. The first VCO band oscillates a frequency when the driving power is applied to the first output terminal. The second VCO band oscillates the frequency when the driving power is applied to the second output terminal. The resonant frequency switching portion converts the output frequency of the second VCO band to a frequency for PCS.
|
