US Patent 11405041 Programmable frequency DLL

A DLL circuit that has a programmable output frequency is provided. In various embodiments, the DLL circuit comprises an input configured to receive an input clock defining an input clock period; an output configured to provide a DLL output clock; a delay line configured to receive the input clock, wherein the delay line comprises a plurality of delay stages, each configured to generate one of a plurality of delay line output clocks, each of the delay line output clocks having a phase relative to the input clock based on a delay of the delay line; a clock generation circuit, configured to generate the DLL output clock based on a selected plurality of the delay line output clocks; and a control circuit configured to select which of the delay line output clocks the clock generation circuit uses to generate the DLL output clock.