Transient tests on rad-hard microprocessor and memory devices of CMOS/SOS design were carried out with the Boeing Linac as the electron pulse source of 40 ns duration. Mean temporary and permanent upset levels were determined to be 1.1Ã1010 and 1.3Ã1010 rads (Si)/s for the microprocessor, and 1.3Ã1010 and 5.1Ã1010 rads (Si)/s for the memory, respectively. All of these values correspond to the worst case exposure conditions which were found to be static rather than dynamic (i.e., a transition state). Storage pattern sensitivity for both device types during exposure was also determined to be a dominant-zero pattern, that is, a few ones in a field of zeroes in the case of the microprocessor, and a single one in a field of zeroes for the memory. Transient annealing measurements on the microprocessor indicated a recovery time of 20 Â¿s to 87% of VOH following a 27 kilorad dose/pulse for a 1.8 Â¿s electron pulse.