Scalable, compact, nanosecond pulse generator with a high repetition rate for biomedical applications requiring intense electric fields

A high repetition rate, high voltage pulse generator has been developed that scales up the output voltage of a recently reported compact, nanosecond pulse generator that is currently being used in various biomedical applications, including experiments into the mechanisms that drive cellular electropermeabilization and plasma generation for an endodontic disinfection tool. This single-stage, nanosecond architecture is based is composed of a bank of power MOSFETs, a linear network of inductors and capacitors, and a bank of junction recovery diodes; it was reported to feature an output pulse amplitude voltage to input voltage ratio between 5 and 6. Since commercially available power MOSFETs tend to be limited to 1 kV, the output amplitude of the single-stage pulse generator does not exceed 5 or 6 kV. To combat this limitation, two different architectures have been developed that enable scaling of the output voltage. The first of these increases the voltage input to the pulse-forming network by means of a solid-state Marx bank that employs power MOSFETs arranged in a series-parallel arrangement to handle the high voltage and high current requirements of the switching stage. The second architecture employs a saturating transformer to handle the high current. Each of these has its own advantages: the first architecture has a shorter trigger-to-output delay time and is capable of producing low-jitter pulses with a linear input-output voltage relationship; whereas, the architecture with a saturating core features fewer components and reduced complexity. Prototypes of both architectures have been designed, built, tested, and are currently being used.