Membrane keyboard scan circuit, scan method and keyboard having the same

摘要

A membrane keyboard scan circuit, a scan method and a keyboard having the same are provided. A row scan-port circuit of the scan circuit comprises a first and a second select branches corresponding to a first type of the membrane keyboard and a second type of the membrane keyboard respectively. A column scan-port circuit of the scan circuit comprises a fifth switch connected between a power supply voltage and an output port of the row scan-port circuit and a sixth switch connected between a ground line and the output port. The column scan-port circuit performs a scan output process to provide a row-scan timing signal to a key circuit of the membrane keyboard such that one of the first and the second select branches generates a sensing signal when the key circuit is triggered.