QUALCOMM Incorporated
METHOD OF GENERATING PRECISE AND PVT-STABLE TIME DELAY OR FREQUENCY USING CMOS CIRCUITS

Abstract:

A method of generating precise and PVT-stable time delay or frequency using CMOS circuits is disclosed. In some implementations, the method includes providing a reference voltage using a resistive module at a positive input terminal of an operational amplifier, coupling gates of a pair of p-type metal oxide semiconductor (pMOS) transistors and a compensation capacitor to an output terminal of the operational amplifier to generate a first bias signal, and coupling a pair of n-type metal oxide semiconductor (nMOS) transistors to a negative terminal of the operational amplifier to generate a second bias signal at the negative terminal, wherein the pair of nMOS transistors is substantially the same as a pair of nMOS transistors in the CMOS delay circuit.