摘要 |
A capacitance-sensitive switch unit including a capacitive element operable to produce an effective capacitance dependent upon the physical proximity of objects relative thereto, a first selector signal input connected to the capacitive element to enable a first input signal to charge the effective capacitance, a threshold signal producing circuit connected to the capacitive element, for producing a threshold signal which is rendered active when the effective capacitance charges to a pre-defined potential, a switching circuit for selectively connecting the capacitive element to the threshold signal producing circuit in response to a switching signal and a discharge control circuit connected to the capacitive element, for selectively discharging the effective capacitance independently of the input signal, in response to a discharge signal. Also disclosed is a switch array employing structure similar to the above.
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