Detection circuit

Abstract

The invention discloses a detection circuit which contains column lines, row lines, switch components, capacitors and a processing unit. The switch components are arranged between the corresponding column lines and the corresponding row lines, and when the switch components are pressed, the corresponding column lines and row lines electrically make contact with each other; each capacitor is arranged at one end of the corresponding column line; the processing unit is electrically connected with the ends, with the capacitors, of the column lines and one end of each row line and used for sequentially outputting scanning signals to each row line; and when one row line sends the scanning signal and detects that the first column line receives the scanning signal, the processing unit judges whether or not the corresponding first switch component is switched on according to the charging time of the capacitor corresponding to the first column line, wherein the first switch component correspondsto the row line and the first column line. According to the detection circuit, keys of a keyboard can be arranged arbitrarily without special design, whether or not a ghost key is generated can be effectively judged, and a multi-key rollover technology is achieved.

Description

technical field [0001] The present application relates to a detection circuit, in particular to a circuit and method capable of detecting keyboard ghost keys. Background technique [0002] A general computer keyboard or telephone keyboard is usually composed of a matrix formed by multiple scan lines and multiple return lines. When the user presses a key on the keyboard, the corresponding scan lines and return lines will Sexual contact to form a circuit, and by detecting the voltage difference of each group of circuits, it can be known whether the button is pressed. However, when three buttons are pressed at the same time, if the three buttons form a 2×2 matrix, the corresponding two scan lines and the two scan lines will form four groups of loops, and the system will misjudge that four buttons are simultaneously pressed. Depress, wherein, the misjudged fourth button is called ghost key (ghostkey). [0003] In the manufacture of traditional keyboards, keyboard keys must be ...

AI Technical Summary

Problems solved by technology

[0003] In the manufacture of traditional keyboards, keyboard keys must be deliberately arranged to prevent ghost keys from possible combination keys, which will lengthen and complicate the wiring of the overall keyboard, and cause disadvantages such as an increase in line impedance

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