US Patent 7129854 Electronic device with force sensing key

An electronic device with a force sensing key (200) has a switch (280), a first force sensing region (290) for acquiring a first force value, a second force sensing region (290) for acquiring a second force value, and a processor for determining a selected function for the key (200) based upon the first force value and the second force value when the switch (280) is activated. The first force sensing pad (290) and the second force sensing pad (290) use a partially resistive material (250) that exhibits a force-to-voltage response value. By forming the switch (280) as a dome (225) switch, the force sensing key (200) provides crisp tactile feedback to a user. The force sensing key (200) can be configured for a variety of applications and user preferences by varying the architecture of the actuator (270).