Touch chip, capacitive touch screen, capacitive active pen, and two-way communication method between capacitive touch screen and capacitive active pen

Abstract

A touch control chip (260), connected to a capacitive touch screen (20), the capacitive touch screen (20) including a plurality of driving electrode channels (Y), a plurality of sensing electrode channels (X) and a display module (220 ), the touch chip (260) includes a control unit (261), a drive circuit (262), a sensing circuit (263) and a multiplexing unit (264) electrically connected to each other. The control unit (261) drives the induction circuit (263) to detect the interference signal from the display module (220), and performs spectrum analysis on the interference signal, and selects the minimum intensity value of the interference signal or the difference from the minimum intensity value is less than a set value After the frequency point of the threshold is used as the working frequency point, the information of the working frequency point is sent to a capacitive active pen (10) applied to the capacitive touch screen (20), and the capacitive active pen (10) is selected according to the working frequency point. drive frequency.

Description

technical field [0001] The invention relates to a touch chip applied to a capacitive touch screen, in particular to a touch chip capable of two-way communication between a capacitive touch screen and a capacitive active pen and allowing the capacitive active pen to dynamically switch output signal frequencies. Background technique [0002] With the popularization of capacitive touch screens, the matching application of capacitive active pens and capacitive touch screens is becoming more and more extensive. Such as figure 1 As shown, a typical capacitive touch screen 2 with a display function has a touch screen sensing layer 21, a display module 22, a glass cover 23, and an intermediary between the touch screen sensing layer 21 and the display module 22. Optically clear adhesive layers (OCA; optically clear adhesive) 24 and 25 between the touch screen sensing layer 21 and the glass cover 23 . The touch screen sensing layer 21 includes driving electrode channels and sensing ...

AI Technical Summary

Problems solved by technology

Since the distance between the display module 22 or the driving signal layer of the display module 22 and the sensing electrode channel is smaller than the distance between the tip of the capacitive active pen 1 and the sensing electrode channel, this interference signal especially has a larger When the signal strength is low, the coordinates of the capacitive active pen 1 will shake, pop up, etc., which will affect the normal operation of the user.

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