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US 10,761,633 B2Granted
Touch display device, touch-driving circuit, and touch-sensing method
AssigneeLG Display Co., Ltd.
InventorsHyeongWon Kang, HongJu Lee
Life of this patent
Estimating the term…
Abstract
A touch display device, a touch driving circuit, and a touch-sensing method are disclosed in which control operation timing at which a charge control circuit connected to an input terminal of a pre-amplifier is controlled in consideration of a difference in a location or time constant for each touch electrode. Accordingly, unnecessary variation in a signal-to-noise ratio for each touch electrode can be reduced, and thus touch sensitivity can be improved.
Claims24
A touch display device, comprising:
- a touch screen panel comprising a plurality of touch electrodes;
- and
- a touch-driving circuit configured to supply a driving signal to the touch screen panel and receive a sensing signal from the touch screen panel,
- wherein the touch-driving circuit comprises:
- a pre-amplifier having a first input terminal to which the sensing signal for a touch electrode to be sensed among the touch electrodes is input;
- and
- a charge control circuit electrically connected between the first input terminal of the pre-amplifier and a charge control signal input terminal to which a charge control signal is input,
- the charge control circuit comprises a charge control switch and a charge control capacitor connected between the first input terminal of the pre-amplifier and the charge control signal input terminal by the charge control switch, and
- controls a charge input to the first input terminal of the pre-amplifier by turning on the charge control switch and changing a voltage level in the charge control signal after a first control time passes from a time point at which the driving signal changes from a first voltage level to a second voltage level, and
- the first control time is changed according to a location or a time constant of the touch electrode.
7 more elements
A touch-driving circuit, comprising:
- a pre-amplifier having a first input terminal configured to output a driving signal to touch electrodes and receive a sensing signal for the touch electrode to be sensed among the touch electrodes;
- and
- a charge control circuit electrically connected between the first input terminal of the pre-amplifier and a charge control signal input terminal to which a charge control signal is input,
- wherein the charge control circuit comprises a charge control switch and a charge control capacitor connected between the first input terminal of the pre-amplifier and the charge control signal input terminal by the charge control switch, and
- controls a charge input to the first input terminal of the pre-amplifier by turning on the charge control switch and changing a voltage level in the charge control signal after a first control time passes from a time point at which the driving signal changes from a first voltage level to a second voltage level, and
- the first control time is changed according to a location or a time constant of the touch electrode.
3 more elements
A method of sensing a touch, the method comprising:
- outputting a driving signal to touch electrodes by a touch-driving circuit;
- receiving a sensing signal from the touch electrodes by the touch-driving circuit;
- and
- generating sensing data based on the sensing signal and outputting the generated sensing data by the touch-driving circuit,
- wherein, during the outputting of the driving signal, a charge control capacitor is connected between a first input terminal to which the sensing signal is input in the touch-driving circuit and a charge control signal input terminal to which a charge control signal different from the driving signal is input in the touch-driving circuit after a first control time passes from a time point at which the driving signal starts changing from a first voltage level to a second voltage level, and
- the charge control signal changing from a third voltage level to a fourth voltage level is applied to one electrode of the charge control capacitor, and
- the first control time is changed according to a location or a time constant of the touch electrode.
4 more elements
Dependencies are inferred from the claim text.