Composite function keyboard circuit
AssigneePrimax Electronics Ltd.
InventorsYi-Liang Chen, Chih-Chen Chang, Chien-Ming Li
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AssigneePrimax Electronics Ltd.
InventorsYi-Liang Chen, Chih-Chen Chang, Chien-Ming Li
Estimating the term…
A composite function keyboard circuit includes a first matrix circuit, a first bias resistor group, a second matrix circuit, a second bias resistor group and a controller. Each switch unit in the first matrix circuit is an ink-type force sensing switch. A resistance of the ink-type force sensing switch is variable according to a pressing mode of a keypress action. An electrical connection path is formed between the ink-type force sensing switch and the corresponding bias resistor of the second bias resistor group. When the ink-type force sensing switch is electrically conductive, a divided sensing voltage is generated by the electrical connection path, and the controller generates a corresponding key control instruction according to a level of the divided sensing voltage. Furthermore, the cooperation of the first matrix circuit and the first bias resistor group can achieve a ghost key preventing function.
A composite function keyboard circuit, comprising:
Dependencies are inferred from the claim text.