| 摘要 |
PURPOSE: To obtain the frequency synthesizer in which a time required to select a frequency is reduced. CONSTITUTION: The synthesizer is provided with a reference frequency generating section 1 generating a reference frequency, a voltage controlled oscillator 2 whose oscillating frequency changes with an input voltage, an output frequency divider 3 frequency-dividing an output frequency of the voltage controlled oscillator 2, and a time comparator section 4 comparing a time when a state change in a signal from the reference frequency generating section 1 till a signal from the output frequency divider 3 changes its state with a signal from the reference frequency generating section 1 returns its state till a signal from the output frequency divider 3 restores its state and increasing/decreasing a voltage having been outputted so far in response to the error, and an output of the time comparator section 4 is given to the voltage controlled oscillator 2. |
