AN-1028 Single Wire Interface/GPIO Expander
A Single Wire Interface (SWI) system is designed to reduce the number of wires in serial data communication. It is particularly useful in mobile devices because it increases the reliability of the product (fewer contact points) while reducing its size and cost. The design objective is to transfer digital data using a one wire protocol. Other possible uses are GPIO expander, serial 1 to 6 line decoder for status indicators, etc. This SWI works by counting how many rising edges on the serial input occurred, up to 64 (6-bits). The binary equivalent from a counter is then presented to latched outputs 40mS after the last serial input.
- AN-1028.zip- (440 KB)
Single Wire Interface (SWI), GPIO Expander, Decoder