A touch screen, its driving method and display device

Abstract

The invention discloses a touch screen, a driving method for the touch screen and a display apparatus. A level switching circuit is added between a driving signal line and a touch driving electrode, so that the driving signal line only needs to provide a logic pulse signal, a driving function does not need to be realized, the driving signal line can be made thinner, and narrow bezel design is facilitated; at the same time, more driving signal lines can be made under the same size, so that the touch sensitivity is improved and a power signal line only needs to be made relatively wide for reducing impedance; moreover, driving signals perform time-sharing driving in sequence, so that a load of the power signal line is the same as that of a single driving signal line in original design and the power consumption is not increased; and a driving line is replaced with one power signal line, so that the problems of overlarge impedance and large impedance difference of the driving signal line in the original design can be effectively improved by only reducing the impedance of the power signal line, and a touch function can be improved.

Description

technical field [0001] The invention relates to the field of display technology, in particular to a touch screen, a driving method thereof and a display device. Background technique [0002] With the development of touch screen technology, the touch technology has been developed rapidly. At present, the single-chip touch screen mainly adopts the principle of capacitive sensing. Generally, capacitive touch screens include self-capacitive touch screens and mutual-capacitive touch screens, among which mutual-capacitive touch screens can realize multi-point recognition and become the mainstream. [0003] The structure of the mutually capacitive single-chip touch screen in the prior art is as follows: figure 1 As shown, the touch screen has touch driving electrodes 01 and touch sensing electrodes 02 interlaced with each other. A coupling capacitor is formed between the two electrodes. The driving signal line TX sends the driving signal, and the sensing signal line RX receives th...

AI Technical Summary

Problems solved by technology

The touch driving scan is progressive scanning, in which the driving signal input by the driving signal line TX is a pulse signal sent sequentially in time-sharing. The signal on the line TX has a large impedance difference due to the different trace lengths. The longer signal line has a larger impedance, which eventually leads to a large difference in the driving signals input to each touch driving electrode. In order to achieve a relatively large For a good touch effect, the voltage amplitude of the signal on the driving signal line TX is relatively large. For example, the amplitude of the driving signal of a 21.5-inch single-chip touch screen is over 30V, which increases the workload of the touch chip. It is also necessary to add a boost chip on the periphery of the touch chip, which makes the peripheral circuit more complicated and increases the production cost

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