摘要 |
A phase-locked loop includes an oscillator, a phase detector coupled to the oscillator, a charge pump coupled to the phase detector, a filter coupled to the charge pump, a voltage controlled oscillator, and a fractional frequency divider. The voltage controlled oscillator sends a VCO signal to the divider which sends an output signal to the phase detector. The divider comprises a prescaler that divides the VCO signal by an integer number and the divider emits a first signal representing the result of the division. The phase-locked loop comprises an accumulator coupled to the divider and a digital-analog converter that receives the first signal and outputs a DAC signal aligned with the first signal. The phase-locked loop comprises a circuit coupled to the digital-analog converter and to the prescaler to synchronize the DAC signal with a signal output from the prescaler.
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