Patent attributes
An electrosurgical system includes a generator for generating radio frequency (RF) power, and an electrosurgical instrument including at least three electrodes. The generator comprises an RF output stage having at least a pair of RF output lines, a power supply coupled to the output stage for supplying power to the output stage, and a controller capable of varying the RF power signal supplied to the output lines. The system also includes a selection circuit having at least three output connections each in electrical connection with a respective one of the at least three electrodes. This selection circuit operates to vary the coupling between the RF output stage and the three or more output connections. A switching device operable by the user causes the selection circuit to vary the electrode or electrodes to which RF power is supplied, and also causes the RF power signal supplied to at least one of the at least three output connections to vary depending on the electrode or electrodes to which RF power is supplied. In one arrangement of the selection circuit, one of the electrodes has no direct connection to the output stage of the generator and is connected via a capacitor to another of the electrodes.
