Patent ID: 7927328

Claim:
An electrosurgical system comprising: a generator configured to generate at least one electrosurgical coagulation waveform, the generator includes a closed loop control system that controls the at least one electrosurgical coagulation waveform, the closed loop control system including: a sensor configured to sense at least one of a tissue property and an energy property and transmit the at least one of a tissue property and an energy property to a gain controller as a voltage sensor signal having an amplitude; the gain controller configured to process the voltage sensor signal to reduce the amplitude of the voltage sensor signal and obtain a signal to noise ratio of the voltage sensor signal within a predetermine range; the gain controller being a voltage gain controller that includes: a sensor voltage scaler control configured to scale the amplitude of the voltage sensor signal and to generate a scaled sensor signal; a gain control configured to process a variable DC level control signal to generate a gain control signal; and a multiplier coupled to the sensor voltage scaler and the gain control, the multiplier configured to multiply in real-time the scaled sensor signal and the gain control signal to normalize the voltage sensor signal independent of the amplitude thereof; and a microprocessor coupled to the generator and configured to adjust the at least one electrosurgical coagulation waveform as a function of the voltage sensor signal.