A COMMANDABLE PULSE-HEIGHT ANALYSIS SYSTEM BASED ON CUSTOM VLSI ASICSFOR THE CASSINI SPACE MISSION

We have implemented a new commandable threshold PHA-accumulation unit for the MIMI/LEMMS particle detection instrument of the Cassini missio n to Saturn. The Implementation is based on two full custom VLSI ASICs specifically designed, fabricated, and space qualified for this proje ct. The present system overcomes common fine tuning pre-flight and in- flight calibration difficulties associated with conventional fixed thr eshold systems of past missions, while significantly reducing weight a nd power. A brief description of the design as well as experimental re sults will be presented.