MODULAR BATTERY POWERED HANDHELD SURGICAL INSTRUMENT AND METHODS THEREFOR

Disclosed is a method of controlling a modular battery powered handheld surgical instrument. The surgical instrument including a battery, a user input sensor, a controller, a radio frequency (RF) drive circuit, an ultrasonic transducer, ultrasonic transducer drive circuit, and an end effector. The end effector including an electrode electrically coupled to RF drive circuit, an ultrasonic blade acoustically coupled to the ultrasonic transducer, and a sensor to measure tissue parameters. The method includes applying an RF current drive signal to the electrode by the RF drive circuit; applying an ultrasonic drive signal to the ultrasonic transducer by the ultrasonic transducer drive circuit to acoustically excite the ultrasonic blade; controlling intensity, wave shape, and/or frequency of the RF current drive signal and the ultrasonic drive signal on a sensed measure of a tissue or user parameter.