Adaptive resolution circuit

摘要

Apparatuses and methods of adaptive resolution circuits are described. One apparatus includes an input node coupled to a capacitance sense pin coupled to an electrode of a sense array and a capacitance-sensing circuit coupled to the input node and comprising an integrator configured to measure a capacitance with a first resolution. An adaptive resolution circuit is coupled to the capacitance-sensing circuit and the input node and is configured to selectively modify an integration capacitance of the integrator to set the integrator to measure the capacitance with a second resolution.

主权项

1. An apparatus comprising:
an input node coupled to a capacitance sense pin coupled to an electrode of a sense array; a capacitance-sensing circuit coupled to the input node, wherein the capacitance-sensing circuit comprises:
a signal generator coupled to a second capacitance sense pin coupled to a second electrode of the sense array;an integrator configured to measure a first mutual capacitance of an intersection between the electrode and the second electrode with a first resolution;a first integrator capacitor coupled between the input node and an output of the integrator; and an adaptive resolution circuit coupled to the capacitance-sensing circuit and the input node, wherein the adaptive resolution circuit is configured to selectively modify an integration parameter to set the integrator to measure a second mutual capacitance of the intersection with a second resolution, wherein the integration parameter is an integration capacitance of the integrator, and wherein the adaptive resolution circuit comprises:
a second capacitor;a comparator coupled to the output of the integrator; anda switch coupled to an output of the comparator, wherein the comparator is to selectively switch the second capacitor in parallel to the first integrator capacitor of the capacitance-sensing circuit to modify the integration capacitance of the integrator for the second resolution.