Phase-locked loop circuit including a plurality of capacitor cells and method of controlling the same

Abstract

A phase-locked loop circuit includes an oscillator including a plurality of capacitor cells, and a control logic circuit that receives an output from the oscillator. The control logic circuit compares a target frequency with a first frequency of a first signal output from the oscillator, generates a first input code to control at least a portion of the plurality of capacitor cells to output a signal having the target frequency based on the comparison, generates a first output code corresponding to the first input code when the first input code is within a predetermined range of input codes, and controls at least two capacitor cells from among the plurality of capacitor cells based on the first output code. The oscillator may output a second signal having a second frequency through an electrical path including capacitor cells other than grounded capacitor cells from among the plurality of capacitor cells.