Phase lock loop for frequency synthesizer, has oscillator to produce signals with phase difference based on control voltage, and control unit to control multiplexer to provide predetermined fractions of signal

摘要

The loop has a comparator (2) for producing a control voltage based on a difference between a reference and feedback signal. An oscillator produces signals with a phase difference based on the control voltage. A control unit (14) controls a multiplexer (12) to provide fixed fraction of the signals. A divider (8) receives another signal with an average period of a real fraction of the signals to produce feedback signal.