TOUCH SENSING DEVICE

摘要

A device for sensing a touch by measuring a variation in capacitance according to a contact of an object, and measuring a contact position of the object is provided. The device includes a touch screen panel comprising grid electrodes forming a plurality of electrode patterns, the grid electrodes serving as Tx antennas or Rx antennas, a Tx circuit unit connected with the grid electrode to apply an electric signal to the touch screen panel unit, an Rx circuit unit connected with the grid electrodes to sense variations in the capacitance in the plurality of electrode patterns, and a controller configured to control the touch screen panel unit, the Tx circuit unit, and the Rx circuit unit. The Rx circuit unit includes a first operational amplifier, a first feedback capacitor, and a second feedback capacitor. The first feedback capacitor and the second feedback capacitor are connected with the first operational amplifier. Both terminals of the first feedback capacitor and the first operational amplifier are connected through a first switching unit. The first switching unit includes a 1-1 switch and a 1-2 switch, which are controlled to be short-circuited at a first phase of the electric signal. Both terminals of the second feedback capacitor and the first operational amplifier are connected through a second switching unit. The second switching unit includes a 2-1 switch and a 2-2 switch, which are controlled to be short-circuited at a second phase of the electric signal. The controller is further configured to short-circuit the first switching unit and the second switching unit, at different times, to store charges in each of the first feedback capacitor and the second feedback capacitor.

主权项

1. A device for sensing a touch, which measures a variation in capacitance according to a contact of an object, and measures a contact position of the object, the device comprising:
a touch screen panel comprising grid electrodes forming a plurality of electrode patterns, the grid electrodes serving as Tx antennas or Rx antennas; a Tx circuit unit connected with the grid electrode to apply an electric signal to the touch screen panel unit; an Rx circuit unit connected with the grid electrodes to sense variations in the capacitance in the plurality of electrode patterns; and a controller configured to control the Tx circuit unit, and the Rx circuit unit, wherein the Rx circuit unit comprises a first operational amplifier, a first feedback capacitor, and a second feedback capacitor, the first feedback capacitor and the second feedback capacitor are connected with the first operational amplifier, both terminals of the first feedback capacitor and the first operational amplifier are connected through a first switching unit, the first switching unit comprises a switch, which are controlled to be short-circuited at a first phase of the electric signal, both terminals of the second feedback capacitor and the first operational amplifier are connected through a second switching unit, the second switching unit comprises a switch, which are controlled to be short-circuited at a second phase of the electric signal, and the controller is further configured to short-circuit the first switching unit and the second switching unit, at different times, to store charges in each of the first feedback capacitor and the second feedback capacitor.