Wide dynamic range capacitive sensing

摘要

A touch sensor panel configured to detect objects touching the panel as well as objects that are at a varying proximity to the touch sensor panel. The touch sensor panel includes circuitry that can configure the panel in a mutual capacitance (near field) architecture or a self-capacitance (far field and super far field) architecture. The touch sensor panel can also include circuitry that works to minimize an effect that a parasitic capacitance can have on the ability of the touch sensor panel to reliably detect touch and proximity events.

主权项

1. A method of sensing proximity events, comprising:
configuring a touch sensor panel to a self-capacitance architecture; stimulating the touch sensor panel with one or more stimulation signals to generate one or more touch signals; reducing an effect of a parasitic capacitance on the one or more touch signals received from the touch sensor panel by driving a shield with a shield signal of a same frequency and phase as the one or more stimulation signals, wherein the shield is a physical layer separate from other conductive structures in the touch sensor panel; and determining if a proximity event has occurred based on the one or more reduced parasitic capacitance effect touch signals.