Two reports describe a method of assessing the susceptibility of digital electronic equipment to upsets (bit errors) caused by impingement of energetic ions (both protons and heavier ions) in outer space.

The method, which is applicable at the single-component, circuit-board, box, and totalsystem levels, involves terrestrial testing by use of 200-MeV protons only. Unlike in a prior method that involves lower-energy heavier ions, one need not place a test article in a vacuum or remove it from its normal packaging. One of the reports discusses the origin of the present method, describes the procedure for exposing various parts of a test article to an energetic-proton beam and analyzing the resulting test data to obtain radiation susceptibilities, and summarizes the experience gained by use of the method since its inception in the year 1995. The other report discusses mathematical modeling and development of software to estimate the effects of energetic heavier ions on the basis of testing by use of energetic protons only. Among the conclusions reached in this development is that the heavy-ion error rate can be estimated as an orbital-altitudedependent fraction of the proton error rate.

This work was done by William X. Culpepper, Pat M. O’Neill, and Gautam D. Badhwar of Johnson Space Center.

NASA Tech Briefs Magazine

This article first appeared in the November, 2002 issue of NASA Tech Briefs Magazine.

Read more articles from the archives here.