Thirty Megarad CMOS Gate Array for Spacecraft Applications

The recent development, testing, qualification and integration for spacecraft applications of a general purpose, 30 Megarad-hard, CMOS logic gate array having 3000 transistors is reported. Fabricated on the National Semiconductor, Inc. class S radation-hard line, the gate array operates at > 3 MHz (10V) after 107 rad(Si) total dose from a Co60 source. The threshold voltage change is 0.2 volts (0.5 volts) for the n-channel (p-channel) devices under 10V bias conditions. The rad-hard process of the CDI gate array family is mask compatible with the conventional process for cost effective semicustom design. The rad-hard array is presently operating in-orbit on the AMPTE satellite and is planned for instruments to be flown on the CRRES and UARS satellites.