Abstract: A touch-screen interface circuit configured to operate in at least three modes comprises a first resistive x-plate having at least a first x-terminal connected in the first mode to a voltage supply and a second x-terminal connected in first mode to circuit ground; a voltage regulator circuit comprising a floating reference voltage source connected in first mode to the second x-terminal, and to a first input of a touch-screen reference buffer circuit having a second input connected in first mode to the first x-terminal; the voltage regulator circuit arranged to control in first mode a connection between the voltage supply and the first x-terminal; and a second resistive y-plate having at least a first y-terminal and being arranged to apply a wiper contact to the first x-plate, the wiper contact having an x-position, y-position and pressure.

Abstract: A differential amplifier circuit comprising a differential amplifier capacitor and a mismatch error cancellation circuitry, a first pair of capacitors, a second pair of capacitors consisting of switching network. The switching network is arranged to operate in a first configuration wherein the first pair of capacitors is operably coupled to differential inputs of the differential amplifier circuit. The switching network is further arranged to operate in second configuration wherein each capacitor of the first pair of capacitors is operably coupled within a feedback loop between an output and an input of the differential amplifier such that the differential amplifier outputs signals representative of the sampled input voltage signals, and the second pair of capacitors are operably coupled in parallel between the outputs of the differential amplifier such that the second pair of capacitors sample the voltage difference between the outputs.

Abstract: A touch-screen interface circuit configured to operate in at least three modes comprises a first resistive x-plate having at least a first x-terminal connected in the first mode to a voltage supply and a second x-terminal connected in first mode to circuit ground; a voltage regulator circuit comprising a floating reference voltage source connected in first mode to the second x-terminal, and to a first input of a touch-screen reference buffer circuit having a second input connected in first mode to the first x-terminal; the voltage regulator circuit arranged to control in first mode a connection between the voltage supply and the first x-terminal; and a second resistive y-plate having at least a first y-terminal and being arranged to apply a wiper contact to the first x-plate, the wiper contact having an x-position, y-position and pressure.

Abstract: A differential amplifier circuit comprising a differential amplifier capacitor and a mismatch error cancellation circuitry, a first pair of capacitors, a second pair of capacitors consisting of switching network. The switching network is arranged to operate in a first configuration wherein the first pair of capacitors is operably coupled to differential inputs of the differential amplifier circuit. The switching network is further arranged to operate in second configuration wherein each capacitor of the first pair of capacitors is operably coupled within a feedback loop between an output and an input of the differential amplifier such that the differential amplifier outputs signals representative of the sampled input voltage signals, and the second pair of capacitors are operably coupled in parallel between the outputs of the differential amplifier such that the second pair of capacitors sample the voltage difference between the outputs.