Radiation tolerance must be investigated when using COTS components in space. The low price of COTS components allows for “board level testing”, where a whole board is subjected to irradiation, instead of individual components independently. The benefits are lower product assurance costs and shorter development schedules and has been successfully applied for flight equipment operating on in-orbit demonstrators and constellations. Nevertheless, the limitations of this method aren't fully understood, and there is currently no standard test methodology. Our proposal is to validate the use of this method focusing on Total Ionizing Doses (TID) tests. These tests are usually required to be performed systematically or periodically, since a significant lot-to-lot variability in ionizing dose response can be observed in some cases. The goal of this study is to compare the results of irradiations at board level and at component level, and to assess the limitations of the board level technique accordingly. In order to achieve this goal, irradiations would be performed on electronic boards designed for space equipment (with either COTS or Hi-Reliability components on board). The components on these boards would have been fully validated according to existing space standards: - TID radiation validation tests performed according to ECSS 22900 specification, on the lots mounted on the boards - Electronic board worst-case analysis performed according to ECSS-Q-ST-30C and ECSS-Q-HB-30-01A, including radiation-induced parametric drift, temperature-induced parametric drift and ageing drift. Post irradiation measurements will be compared on the full board with the theoretical drift established in the worst case analysis, at several temperatures, to assess the relevance and limitations of this test methodology.
