Td converter, pll circuit, td converting method, and clock generating method

Abstract

Provided is a TD converter including: a plurality of oscillators which at least include a first oscillator and a second oscillator receiving control signals input thereto, respectively, and operating in operating modes with oscillation frequencies different from each other, respectively, wherein each control signal indicates a time difference between a reference clock and a target clock; and a computation circuit which calculates a digital output value depending on the time difference, by using a plurality of pieces of phase information retained according to the reference clock in the plurality of oscillators, respectively.