Digital clock waveform generator and method for generating a clock signal

Abstract

A digital clock waveform generator and method for generating a clock signal are provided for a microprocessor or other digital circuit to provide on chip generation of internal clock signals having the same frequency as or a higher or lower frequency than an externally applied clock signal. In one embodiment, the waveform generator includes a delay chain and a control unit that matches the propagation delay of the delay chain to the period of an input timing signal. The waveform generator provides precise control of the duty cycles of the internally generated clock signals, and allows for rapid starting and stopping of the internal clock signals for power reduction functions. The waveform generator may further provide a system clock, and may include circuitry to precisely control the phase relationships between the various clock signals. The waveform generator is easily manufactured with digital circuitry that automatically compensates for changing environmental conditions such as operating voltage and temperature.