Control circuit and method of capacitance type touch control panel and capacitance type touch control panel module

Abstract

The invention provides control circuit and method of a capacitance type touch control panel and a capacitance type touch control panel module. The control circuit comprises the following structure that: a modulator provides a first signal and a second signal which has the same phase with the first signal; a multiplexer is coupled with the capacitance type touch control panel and the modulator, provides the first signal to a first trace and provides the second signal to a second trace; and a demodulator is coupled with the multiplexer and demodulates the signal on the first trace by a reference signal. Each trace on the capacitance type touch control panel is charged and discharged by a scanning signal, and the signal of the adjacent trace of the trace or a lower grounding layer, which hasthe same phase with the scanning signal, is provided so as to lower the parasitic capacitance between the scanned trace and the grounding layer or other traces, thereby lowering the basic capacitanceof the capacitance type touch control panel, increasing the induction quantity of the control circuit, providing a shielding effect, lowering the noise interference and enhancing the efficacy of the capacitance type touch control panel.

Description

technical field [0001] The present invention relates to a capacitive touch panel, in particular to a control circuit, method and application of the capacitive touch panel. Background technique [0002] Capacitive touch panels are currently widely used in notebook computers, mobile phones, personal digital assistants, and multimedia playback panels because of their thinness, compactness, power saving, and durability. Capacitive touch panels are generally based on printed circuit boards, glass or plastic films, and metal, indium tin oxide conductive films or other material patterns are printed on them as sensors. According to different applications, the shape and shape of the sensors Size also varies. When a conductor such as a stylus or a finger touches the touchpad, it will cause a capacitance change on the sensor. The control circuit detects the capacitance change on the sensor to obtain the information input by the user, and then perform touch control. Therefore, In the ...

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Problems solved by technology

[0003] However, in addition to the amount of capacitance change, the performance of a capacitive touch panel is also related to its basic capacitance (C BASE ) related, when the basic capacitance is high, the capacitance change becomes insignificant, and the induction is not easy, so the performance is reduced. In other words, the performance of the capacitive touch panel is proportional to ΔC / C BASE , although the existing differential detection method increases the amount of capacitance change, it also increases the parasitic capacitance between adjacent sensors, making the basic capacitance of the capacitive touch panel high, so the degree of performance improvement is limited

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