KEY OPERATION DEVICE AND MOBILE TERMINAL DEVICE

摘要

Disclosed is a key operation device for detecting an open/close state of key switches using row and column signal lines. The key switches include: 1^st to 4^th key switches each corresponding to a key for inputting a direction; and ten-key switches correspond one-to-one to keys of a ten-key pad. The 1^st and 2^nd key switches are both coupled to one of the row signal lines and each to a different one of two of the column signal lines. The 3^rd and 4^th key switches are both coupled to another one of the row signal lines and each coupled to a different one of the two column signal lines to which the t and 2^nd key switches are respectively coupled. None of the ten-key switches is coupled to either of the two row signal lines to which the 1^st and 2^nd or 3^rd and 4^th key switches are coupled.