Patent ID: 7033351

Claim:
A system for performing thermal cautery system on body tissue, said system comprising: a thermal cautery device, said thermal cautery device comprising a resistive heating element mounted on means for pressing the resistive heating element into contact with body tissue; a switching power supply; and a control system comprising a means for operably connecting the switching power supply to the resistive heating element to provide power to the resistive heating element; and a means for identifying the thermal cautery device connected to the switching power supply, wherein the control system controls operation of the thermal cautery device based on the identity of the thermal cautery device; and wherein the means for identifying the thermal cautery device comprises: an identification resistor electrically connected to the thermal cautery device, said identification resistor having a pre-determined resistance value; and a reference resistor placed in series with the identification resistor when the thermal cautery device is electrically connected to the switching power supply, said reference resistor also electrically connected to ground such that an identifying voltage develops across the reference resistor when power is applied to the reference resistor and the identification resistor; and a comparison resistor electrically connected to the switching power supply and to ground, wherein a reference voltage develops across the comparison resistor when power is applied to the comparison resistor; and a comparator, wherein the positive terminal of the comparator is electrically connected to the identifying voltage and the negative terminal of the comparator is electrically connected to the reference voltage; wherein the comparator produces an output signal if the identifying voltage is higher than the reference voltage, said output signal indicating that a particular thermal cautery device is operably connected to the power supply.