| 摘要 |
<p>A push-button actuated input is designed for low cost, mass production and avoids the need for moving electrical contacts. The push-button (3) is actuated to apply pressure to a piezo-electric crystal producing a signal over a load resistor (5). The output signal is coupled into a CMOS integrated circuit (6) with protective resistors (7, 9) and diode (10, 11). The circuit operates in an inverter (12) mode and generates an output if a threshold valve is exceeded. The protective diodes and resistors are sized to handle the range of signals generated from the crystal due to different contact pressures.</p> |
