An electrosurgical generator is provided. The generator includes a DC-DC buck converter configured to output a DC waveform, the DC-DC buck converter including at least one first switching element operated at a first duty cycle a DC-AC boost converter coupled to the DC-DC buck converter and including at least one second switching element operated at a second duty cycle, the DC-AC boost converter configured to convert the DC waveform to generate at least one electrosurgical waveform and a controller coupled to the DC-DC buck converter and the DC-AC boost converter and configured to adjust the first duty cycle and the second duty cycle to operate the at least one electrosurgical waveform in at least one of constant current, constant voltage, or constant power modes.
