System including circuitry for controlling a characteristic of a periodic signal and method for adjusting a signal

Abstract

System and circuitry controlling characteristics of periodic signals. In one embodiment adjustment circuitry modifies periodic signal characteristic. A phase detector generates analog input signals indicative of a phase difference between the periodic signal and a reference signal. Conversion circuitry translates the analog input signals into digital signals. Signal driving circuitry, comprising a current source, provides control signals to the signal driving circuitry based on the digital signals. First input circuitry provides a first adjustment signal to the adjustment circuitry. Second input circuitry provides a second adjustment signal to the adjustment circuitry in response to the control signal. The first adjustment signal is based on input of analog signals to a circuit element in the first input circuitry to control the first adjustment signal. The second input circuitry is responsive to the control signal to provide the second adjustment signal with the digital version of the input signals.