Touch input device

A touch input device, comprising:

• a touch plate, wherein when said touch plate is pressed, an electric capacity of said touch plate is increased, wherein said touch plate comprises plural touch keys, and said plural touch keys comprises:
• M first type touch keys disposed on said touch plate, wherein each of said M first type touch keys has one first touch contact, wherein when one of said M first type touch keys is pressed, said corresponding first touch contact is triggered;
• and
• at least one second type touch key disposed on said touch plate, wherein each of said at least one second type touch key has M separate second touch contacts, wherein when said second type touch key is pressed, said corresponding M second touch contacts are triggered;
• and
• a controlling unit connected with said touch plate for judging whether one of said M first type touch keys and said at least one second type touch key is triggered or not, wherein said controlling unit has M connecting ports, and each of said M connecting ports is correlated with said corresponding second touch contact and said corresponding first type touch key, so that said touch plate comprises (2M−1) touch keys, wherein M is a positive integer, and a number of said first type touch keys is greater than a number of said at least one second type touch key.