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An all solid-state modulator with multi-pulse burst capability, very fast rise and fall times, pulse width agility, and amplitude modulation capability for use with high-speed beam kickers has been designed and tested at LLNL. The modulator uses multiple solid-state modules stacked in an inductive-adder configuration. It provides a nominal 18kV pulse with +/-10% amplitude modulation on the order of several MHz, rise times on the order of 10nS, and can be configured for either positive or negative polarity. The presentation will include measured performance data.

The Beam Research Program at Lawrence Livermore National Laboratory (LLNL) has been developing solidstate modulators for accelerator applications for several years. These modulators are based on inductive adder circuit topology and have demonstrated great versatility with regard to pulse width and pulse repetition rate while maintaining fast pulse rise and fall times. These modulators are also capable of being scaled to higher output voltage and power levels. An explanation of the circuit operation will be presented along with test data of several different hardware systems.

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Large aperture Plasma Electrode Pockels Cells (PEPC) are an enabling technology in the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory. The Pockels cell allows the NIF laser to take advantage of multipass amplifier architecture, thus reducing costs and physical size of the facility. Each Pockels cell comprises four 40-cm x 40-cm apertures arranged in a 4x1 array. The combination of the Pockels cell and a thin-film polarizer, configured in a 4x1 array, form an optical switch that is key to achieving multi-pass operation. Solid-state Plasma Pulse Generators (PPGs) and high current high voltage solid-state Switch Pulse Generators (SPGs) have been developed for use in the PEPC. The solid-state plasma pulse generators initiate and maintain plasma within the cells; each pulser is capable of delivering 60J of energy to each plasma channel. Deployment of the solid-state PPGs has been completed in NIF. The MOSFET-switched SPG is capable of delivering a requisite fast rise time, 17kV flattop pulse to the cells' nonlinear crystals.A complete software and hardware control system has been developed and is currently being tested for use on the solidstate SPGs. Also a transmission line modeling, development, and testing effort is in process, in support of NIFs' Advanced Radiographic Capabilities (ARC). Work is scheduled for completion by the end of the calendar year.

A high current, high voltage, all solid-state pulse modulator has been developed for use in the Plasma Electrode Pockels Cell (PEPC) subsystem in the National Ignition Facility.The MOSFET-switched pulse generator, designed to be a more capable plug-in replacement for the thyratron-switched units currently deployed in NIF, offers unprecedented capabilities including burst-mode operation, pulse width agility and a steady-state pulse repetition frequency exceeding 1 Hz. Capable of delivering requisite fast risetime, 17 kV flattop pulses into a 6 Ω load, the pulser employs a modular architecture characteristic of the inductive adder technology, pioneered at LLNL for use in acceleration applications 1 , which keeps primary voltages low (and well within the capabilities of existing FET technology), reduces fabrication costs and is amenable to rapid assembly and quick field repairs.

AbsiractA solid-state high voltage pulse generator for highspeed beam kicker applications has been designed and tested at Lawrence Livermore National Laboratory. This kicker pulser uses multiple stages stacked in an inductiveadder configuration where the energy is switched from each stage of the adder by a parallel array of MOSFETs. Features include pulse width, format and amplitude agility all at a high pulse-repetition rate. The modulator can drive a 50!?? load at voltages up to 18kV with +/-10% amplitude modulation at several MHz burst frequency. Rise and fall times are on the order of 1 Ons, and the pulser can easily be configured for either positive or negative polarity. The presentation will include test and operational data collected from both the ETA I1 accelerator kicker and resistive dummy loads.