Capacitance test circuit and method for scanning line of capacitive touch screen and touch screen

Abstract

The invention relates to a capacitance test circuit and a capacitance test method for a scanning line of a capacitive touch screen and the touch screen. A capacitance to be tested is connected in parallel with an external capacitance and then is output by a comparator, so that the aim of testing the capacitance is fulfilled. In the capacitance test circuit and the capacitance test method for the scanning line of the capacitive touch screen and the touch screen, the defect of unavailable judgment of whether the touch screen is a non-defective product or not due to unavailable test of the capacitance in the prior art is overcome; moreover, in the test method, a test can be finished before the touch screen is molded and adjustment is performed in time, so that a defective product is transformed into a non-defective product, cost is saved and product yield is increased.

Description

technical field [0001] The invention relates to a scanning line capacitance testing method of a capacitive touch screen, in particular to the method and a corresponding touch screen. Background technique [0002] At present, judging whether the capacitive touch screen is qualified generally needs to test whether the scanning line is conductive, the impedance and the capacitance value. In order to save testing costs, the steps of testing the touch screen are generally completed before molding. At this stage, ITO on the touch screen can only test its conduction and impedance after etching. Although the conduction and impedance test before the touch screen is formed can exclude some defective products from flowing into the next process step, but because there is no test The method of scanning the capacitance value of the line, so it can only be judged whether it is a qualified product by the fluency of finger operation after the touch screen is formed. [0003] Therefore, the ...

AI Technical Summary

Problems solved by technology

[0007] The capacitive touch screen scanning line capacitance testing circuit and method and the touch screen described in the present invention not only overcome the traditional shortcomings of not being able to test the capacitance so as to judge whether the touch screen is a good product, but also the test method can complete the test before the touch screen is formed and adjust the production in time The process reduces the defect rate of the product, saves the cost, and improves the yield rate of the product

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