SCAS285AC March 1993 – April 2022 SN54LVC14A , SN74LVC14A
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
Physically interactive interface elements like push buttons or rotary knobs offer simple and easy ways to interact with an electronic system. Many of these physical interface elements often have issues with bouncing, or where the physical conductive contact can connect and disconnect multiple times during a button push or release. This bouncing can cause one or more faulty transient signals to be passed during this transitional period. These faulty signals can be observed in many common applications: for example, a television remote with bouncing error can adjust the TV channel multiple times despite the button being pushed only once. To mitigate these faulty signals, use a Schmitt-trigger, or a device with hysteresis, to remove these faulty signals. Hysteresis allows a device to remember its history, and in this case, the LVC14A uses this memory to debounce the physical element's signal, or filter the faulty transient signals and pass only the valid signal each time the element is used. In this example, we show a push button signal passed through an LVC14A that is debounced and inverted to the MCU for push detection.