Patent ID: 8432170

Claim:
An integrated circuit comprising: a capacitance-sensing device disposed on an common carrier substrate of the integrated circuit; and a capacitance model circuit disposed on the common carrier substrate, wherein the capacitance model circuit is configured to model a capacitance of an external sense array, and wherein the capacitance model circuit is programmable, wherein the capacitance model circuit comprises: an input comprising a switch coupled to receive a transmit (TX) signal; an output comprising a plurality of switches coupled to output a receive (RX) signal; and a plurality of programmable capacitors coupled to at least one of the input or output, wherein the plurality of programmable capacitors comprises: a first set of one or more capacitors coupled between the input and output; a first set of one or more switches, each coupled to one of the first set of capacitors to turn on and off the corresponding capacitor; a second set of one or more capacitors coupled between a ground potential and the output; and a second set of one or more switches, each coupled to one of the second set of capacitors to turn on and off the corresponding capacitor.