Patent ID: 7974052

Claim:
An apparatus, comprising: an integrated circuit, comprising an input circuit; a first diode including a first anode and a first cathode, with the first cathode coupled to a first voltage, the first anode coupled to the input circuit at a node via a first mechanical switch; a second diode including a second anode and a second cathode, with the second cathode coupled to the node via a second mechanical switch, the second anode coupled to a ground; a resistor coupled to the input circuit between the integrated circuit and the node; and a third mechanical switch coupling the resistor and the integrated circuit and the node, wherein in a first mode of operating, the first mechanical switch and the second mechanical switch are reversibly held in a conducting position, while the third mechanical switch is held in a nonconducting position, and in a second mode of operating, the first and second mechanical switches are held in a nonconducting position, while the third switch is held in a conducting position.