Patent ID: 7554221

Claim:
A pulse generator that generates a voltage pulse that is applied to a load, the pulse generator comprising: a plurality of first voltage cells, each voltage cell having a capacitor in series with a main switch such that all capacitors are connected in series when all main switches are on to generate a voltage pulse that is delivered to a load; and a second voltage cell connected in series with the plurality of first voltage cells, the second voltage cell including: a pair of capacitors in series with a second main switch; at least a first diode arranged with the pair of capacitors such that the pair of capacitors charge in series when the main switch is off and discharge in parallel when the main switch is on; and a ringing circuit that includes: an inductor in series with the pair of capacitors; and a ringing capacitor in parallel with the inductor, wherein the ringing capacitor charges to twice a value of the pair of capacitors and provides droop compensation to the voltage pulse.