Quadrature demodulation for touch sensitive devices

摘要

Demodulation circuits and processes for demodulating touch signals from a touch sensor using the demodulation circuits are provided. The demodulation circuits can include circuitry configured to determine an adjustable phase delay based at least in part on a quadrature component of the touch signal or the phase-adjusted touch signal. The demodulation circuit can further include circuitry for applying the adjustable phase delay to the touch signal to compensate for phase delays in the touch signal caused by the touch sensor and/or other components. The demodulation circuit can dynamically change the adjustable phase delay to compensate for time-varying phase delays caused by the touch sensor and/or other components.

主权项

1. A demodulation circuit configured to:
determine an adjustable phase delay to be applied to a touch signal from a touch panel, the adjustable phase delay determined based at least in part on a phase-adjusted quadrature (Q) component of the touch signal; and apply the adjustable phase delay to the touch signal to generate the phase-adjusted Q component of the touch signal.