US Patent 9060776 Surgical generator for ultrasonic and electrosurgical devices

In accordance with various embodiments, methods for controlling electrical power provided to tissue via a surgical device may comprise providing a drive signal. A power of the drive signal may be proportional to a power provided to the tissue via the surgical device. The methods may also comprise periodically receiving indications of an impedance of the tissue and applying a first composite power curve to the tissue, wherein applying the first composite power curve to the tissue comprises. Applying the first composite power curve to the tissue may comprise modulating a first predetermined number of first composite power curve pulses on the drive signal; and for each of the first composite power curve pulses, determining a pulse power and a pulse width according to a first function of the impedance of the tissue The methods may also comprise applying a second composite power curve to the tissue. Applying the second composite power curve to the tissue may comprise modulating at least one second composite power curve pulse on the drive signal; and for each of the at least one second composite power curve pulses, determining a pulse power and a pulse width according to a second function of the impedance of the tissue.