A touch screen and a mobile terminal

Abstract

The present invention relates to the technical field of touch control, a touch screen is disclosed, a detection unit in the touch screen includes a voltage-current conversion module, a mixing module and a filter sampling module, an input terminal of the voltage-current conversion module is connected with a self-capacitor, the other input terminal is connected with a driving circuit, and the voltage-current conversion module samples the charge generated from the capacitor under the excitation of the excitation signal generated from the driving circuit, converts the charge generated from the capacitor into a current signal, and obtains the change data of the self-capacitance value by detecting the current signal. The embodiment of the invention discloses a touch screen and a mobile terminal,which reduces the area and cost of the touch screen detection circuit, improves the sampling efficiency, and thus improves the anti-interference ability of the detection circuit.

Description

technical field [0001] Embodiments of the present invention relate to the field of touch technology, and in particular to a touch screen and a mobile terminal. Background technique [0002] With the development of smart phones, more and more electronic products use touch buttons. For touch buttons, self-capacitance technology is generally used, that is, the parasitic value of the capacitor itself. When the human hand touches, it is equivalent to introducing an additional capacitor plate, which will affect the capacitance. Therefore, if the capacitance value can be accurately detected, the touch signal can be judged. [0003] However, the inventors have found that there are at least the following problems in the prior art: the existing detection circuit is usually a detection circuit with a switch plus capacitor structure, but if the key capacitance is too large, the capacitance value inside the detection circuit also needs to be large, thereby increasing The area and cost ...

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Problems solved by technology

[0003] However, the inventors have found that there are at least the following problems in the prior art: the existing detection circuit is usually a detection circuit with a switch plus capacitor structure, but if the key capacitance is too large, the capacitance value inside the detection circuit also needs to be large, thereby increasing reduce the area and cost of the touch screen detection circuit; and because the existing charge is first stored and then transferred in one cycle, only one charge transfer can be completed in one cycle, so that the sampling frequency of the circuit is not high, and the resistance of the detection circuit Weak interference ability

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