Frequency Synthesizer and Phase synchronizing control device based on initial phase offsetting

摘要

A frequency synthesizer and a phase locked loop control apparatus therefor are disclosed. A frequency synthesizer including a voltage-controlled oscillator, a phase frequency detector, a charge pump, a loop filter, and a frequency divider uses a difference value between a start frequency and a target frequency obtained by converting an output frequency fed back by the voltage- And an initial phase setter for calculating an optimal initial phase offset and outputting a control signal for phase synchronization of the phase frequency detector in the closed loop state using the optimal initial phase offset.