Silicon Strip Detectors with Custom VLSI Readout Electronics for the SIS Instrument of ACE

We discuss the design and implementation of the trajectory system for the Solar Isotope Spectrometer (SIS) instrument on the Advanced Composition Explorer (ACE) mission. Thin, large area silicon strip detectors instrumented with a custom very large scale integrated circuit (VLSI) pulse height analyzer (PHA) for each strip are used to simultaneously achieve large geometrical factor and the capability for making precise measurements in even the largest solar energetic particle (SEP) events.