SPACE- RADIATION QUALIFICATION OF A MICROPROCESSOR IMPLEMENTED FOR THE INTEL 80186

The Intel 80186 sixteen-bit microprocessor is an example of a high performance device (8 MHz) needed to carry out advanced experimentation on Low Earth Orbit missions. However, this key complex microprocessor is not space-qualified. We will discuss the procedures necessary to qualify a microprocessor for the natural space radiation environment. We also present the results from our single event upset tests on the 80186. The u~set cross-section exhib~ted a threshold of 0.4 MeV-cm /mg, a knee at 7 MeV-cm /mg and an asymptotic value of 5x10-4cm2 • The upset cross-section did not depend on frequency in the 4-8 MHz range and increased by 40 % when conductive heat sinking was eliminated causing a sooe temperature rise. Finally, we show how to estimate the single event upset rate for a typical low earth orbit mission. I