Patent ID: 7586238

Claim:
A micro electromechanical device comprising: a micro electromechanical switch having a movable portion positioned to form an electrical connection between a first electrical contact and a second electrical contact, an electrode formed on the movable portion, the electrode for causing the movable portion to move in response to a driver voltage; a piezo-resistive element, formed on the movable portion, for detecting movement of the movable portion between an open position and a closed position; and a detection circuit, comprising: a first resistor having a first terminal coupled to a first output terminal, and a second terminal; a second resistor having a first terminal coupled to the first terminal of the first resistor, and a second terminal coupled to a first terminal of the piezo-resistive element; a third resistor having a first terminal coupled to the second terminal of the first resistor, and a second terminal coupled to both a second output terminal and to a second terminal of the piezo-resistive element; and a signal source having a first output terminal coupled to the second terminal of the first resistor, and a second output terminal coupled to the second terminal of the second resistor.