Touch panel controller and sensing device including the same
A sensing device includes a touch panel including first and second sensor electrodes, and a touch panel controller acquiring a sensing signal from the touch panel and detecting a user input based on the sensing signal. The touch panel controller acquires the sensing signal from at least one of the first sensor electrodes and the second sensor electrodes in a first mode operating at a first power. The touch panel controller selects a first transmitting electrode, a second transmitting electrode, and receiving electrodes from one of the first sensor electrodes and the second sensor electrodes, inputs a first driving signal to the first transmitting electrode, and inputs a second driving signal having a phase difference of 180 degrees with respect to the first driving signal to the second transmitting electrode in a second mode operating at a second power and a third mode in which a sensing operation is performed.
1 . A sensing device, comprising:
a first electrode configured to receive a first driving signal, and a second electrode different from the first electrode and configured to receive a second driving signal different from the first driving signal;
a plurality of third electrodes disposed between the first electrode and the second electrode and extending in a direction that is the same as directions of the first electrode and the second electrode;
an electric charge amplifier configured to output a first voltage signal corresponding to a change in capacitance between a portion of the plurality of third electrodes and the first electrode, and outputs a second voltage signal corresponding to a change in capacitance between the other portion of the plurality of third electrodes and the second electrode; and
a processor configured to detect a user input using the first voltage signal and the second voltage signal,
wherein the first driving signal and the second driving signal have a phase difference of 180 degrees therebetween.
2 . The sensing device of claim 1 , further comprising:
at least one fourth electrode disposed between the plurality of third electrodes and shielding the first electrode and the second electrode.
3 . The sensing device of claim 1 , further comprising:
an analog-digital converter configured to convert the first voltage signal and the second voltage signal to digital signals,
wherein the processor detects the user input using a differential signal of the first voltage signal and the second voltage signal converted to the digital signals.
4 . The sensing device of claim 1 , wherein the electric charge amplifier includes an operational amplifier, a feedback resister and a feedback capacitor, wherein the feedback resister and the feedback capacitor are connected in parallel and between an inverting input and an output of the operational amplifier.