Patent attributes
A device for touch panel pressure detection includes a plurality of first input/output terminals for a projected capacitance touch panel. The projected capacitance touch panel includes a layer of piezoelectric material disposed between a plurality of sensing electrodes and a common electrode. The device also includes one or more amplifiers. Each amplifier has an inverting input, a non-inverting input and an output. The non-inverting input of the or each amplifier is configured to be switched between a common mode voltage and a capacitance measurement signal. The inverting input of the or each amplifier is configured to drive an input/output terminal based on the capacitance measurement signal. The amplifier is configured such that, when an input/output terminal is connected to a sensing electrode, the amplifier output varies in dependence upon a pressure applied to the touch panel.