The HX2000 and HX2000r gate arrays are performance oriented sea-of-transistor arrays, fabricated on Honeywell's RICMOSTM IV Silicon On Insulator (SOI) process. The HX2000 arrays are for 5V designs only. The HX2000r arrays support 5V and 3.3V operation. High density is achieved with the standard 3-layer metal or optional 4-layer metal process, providing up to 290,000 usable gates. The high density and performance characteristics of the RICMOS (Radiation Insensitive CMOS) SOI process make possible device operation beyond 100 MHz over the full military temperature range, even after exposure to ionizing radiation exceeding 1x106 rad(SiO2). FlipFlops have been designed for a Soft Error Rate (SER) of less than 1x10-11 errors/bit/day in the Adams 90% worst case environment.