Microchip Technology Incorporated
Method and system for sensing impedance change in the local space between electrodes

Abstract:

A receiver stage of a sensor system includes a receiver electrode and a loop filter. The loop filter is configured to activate electrical oscillation and thus the receiver stage when a capacitance measurement reaches a threshold and issue the capacitance measurement upon activation of the receiver stage. The capacitance measurement includes capacitance with respect to an inactive transmitter electrode.