Method for testing capacitive touch chip

Abstract

The invention relates to a method for testing a capacitive touch chip. In the method, a numerical value output by a comparer is compared with a theoretical voltage value to form a parameter, and then the parameter is compared with a preset parameter, therefore, the influence of errors can be overcome, and the defect of incapability of testing a chip because a direct output value is not matched with the preset parameter when the initial of a binary numerical value appearing in a test period is a symbol also can be overcome, and finally whether a chip is qualified or not is accurately judged and rapidly.

Description

technical field [0001] The invention relates to a method for touching a chip, in particular to a method for testing a capacitive touch chip. Background technique [0002] At present, the test method of capacitive touch chip generally uses a comparator, that is, the positive and negative electrodes of the comparator are respectively connected to two capacitors, and the value output by the comparator is compared with the preset theoretical value. It can be judged whether the chip is qualified or not. Please refer to figure 1 As shown, in the test method of this kind of touch chip, if the value of the capacitor C1 is equal to the value of the capacitor C2, the value output by the comparator should be zero, that is, C1-C2=0; if the value of the capacitor C1 is greater than the value of the capacitor The value of C2, the value output by the comparator is a negative value, that is, C1-C2<0; if the value of the capacitor C1 is smaller than the value of the capacitor C2, the va...

AI Technical Summary

Problems solved by technology

[0007] The testing method of the capacitive touch chip according to the present invention effectively utilizes the theoretical voltage value and the preset parameter value when the chip is designed, and overcomes the influence of the error through multiple comparisons, and also overcomes the problem of in one test cycle. When the first bit of the binary value appearing inside is the sign bit, the direct output value cannot match the preset parameters, which leads to the inability to realize the shortcoming of the test chip, and finally realize the accurate and fast judgment of the qualified chip.

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