Patent ID: 8298225

Claim:
A detection circuit for return electrode monitoring, the detection circuit comprising: a transformer including a primary winding and a secondary winding, wherein the secondary winding is operatively coupled to at least one pair of split electrode pads; a controller coupled to the transformer and configured to output a return electrode sense signal to the at least one pair of split electrode pads; at least one first switch coupled to the primary winding and the controller; at least one neutrally-referenced second switch coupled to the controller, wherein the at least one first switch and the at least one neutrally-referenced second switch are disposed on a single die and are configured to activate in response to the return electrode sense signal; and an operational amplifier coupled to the at least one first switch and the at least one neutrally-referenced second switch, the operational amplifier being configured to subtract a noise signal from the return electrode sense signal, wherein the controller is configured to analyze the noise-cancelled return electrode sense signal.