Patent ID: 8625242

Claim:
A system comprising: a transmitter that is implemented on a first integrated circuit; a receiver that is implemented on a second integrated circuit; an isolation barrier that is connected to the transmitter and that is implemented on a third integrated circuit, wherein the first, second, and third integrated circuits are different; a fuse that includes a conductive material, that is connected between the isolation barrier and the receiver, and that is implemented on the third integrated circuit; a current sensor that measures current flow through the fuse; an indicator lamp; and a barrier monitoring module that illuminates the indicator lamp when the current is approximately zero, wherein: the isolation barrier prevents current flow from the transmitter to the receiver when a voltage across the isolation barrier is less than a first breakdown voltage, the isolation barrier short circuits when the voltage across the isolation barrier is greater than or equal to the first breakdown voltage, the conductive material of the fuse oxidizes and opens the fuse when the isolation barrier short circuits, and when open, the fuse has a second breakdown voltage that is greater than the first breakdown voltage.