| 摘要 |
A circuit and method for actuating a display, especially a liquid crystal display, and a keyboard using a common set of conductors. The circuit includes circuits for generating appropriate display potentials, scanning pulses and sensing the scanning pulses. Certain of the display potentials applied to the display device are also applied to the keyboard. Certain of these potentials applied to the keyboard also have a scanning pulse superimposed thereon. Circuits for sensing the scanning pulses are associated with the circuits which generate the other potentials applied to the keyboard; these other potentials preferably float during the generation of the scanning pulses. By using the disclosed circuit, a calculator chip for actuating a multi-character position liquid crystal display and for scanning a keyboard may be packaged in a conventional twenty-eight pin package. By appropriately controlling the circuit, a keyboard can be scanned with negligible effect on the liquid crystal display device.
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