Ohmic sensing
Provided by the ASK Keyboard Dictionary
Also known as: conductive-contact sensing, contact-based sensing
Ohmic sensing is IBM's term for the simplest and most common form of keyswitch sensing, operating on the principle of detecting a key press when electricity sent down one trace in a circuit such as a keymatrix returns to another after the pressed key bridges a set of contacts. As such, this principle is more commonly referred to as "contact-based" or "conductive-contact sensing". This is a principle is shared by most keyswitch designs, whether it is Alps SKCx and SKBx, Cherry ML, MX and MY, IBM membrane buckling springs or buckling sleeves, or dome over membrane keyswitches in question. Keyboards that use ohmic sensing are known as "contact-based keyboards" or "ohmic keyboards". It is believed that "ohmic" refers to Ohm's law as a whole (i.e., operates on basic electric principles) rather than resistance or Ohms as a unit.
