Novel phase locked loop with digital control techniques

A new type of first-order phase-locked loop (PLL) that has good performance and operates with very simple digital control techniques is proposed. This digitally controlled PLL is composed of a clock generator with its frequency close to that of the input signal, a binary quantized phase comparator, a random walk filter an up-down counter, a digital hold circuit, a D/A converter a sawtooth wave generator, and a voltage comparator. Performance characteristics of the loop are analyzed theoretically and verified by experiments