Systems and methods to create offset signal using sinewave generator with programmable amplitude and phase

摘要

A system for generating a control signal for a capacitive sensor includes a waveform generator configured to generate a digital waveform, a first sigma-delta modulator (SDM) configured to generate a first output corresponding to the control signal based on the digital waveform and first adjustment data and a second SDM configured to generate a second output corresponding to an offset signal based on the digital waveform and second adjustment data. The first SDM is configured to selectively adjust a phase and an amplitude of the control signal and the second SDM is configured to selectively adjust a phase and an amplitude of the offset signal.