Patent attributes
A force sensing resistor (FSR) includes a substrate having separated electrically conductive traces and another substrate having a resistive layer in which the substrates are subjected to a biasing force such that the substrates contact one another with the resistive layer electrically connecting the traces with a resistance inversely dependent on the biasing force. Upon an external force applied towards a substrate, the substrates contact one another with a total force which is the sum of the forces with the resistive layer electrically connecting the traces with a resistance inversely dependent on the total force. An FSR output which is a function of the resistance is measured. Whether a change in magnitude of the FSR output during a time interval is greater than a threshold is determined. A touch applied on the FSR is detected during the time interval if the change is greater than the threshold.
