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Radiation tests of advanced flash memories including, multi-level flash technology, are compared with results from previous generations. Total dose failure levels are comparable to or lower than those of older technologies, but are likely still caused by degradation of the internal charge pump. Small numbers of read errors were observed during single event tests of the multi-level devices that appear to be caused by shifts in the sense amplifier detection levels or cell threshold shifts and rather than loss of electrons off the floating gate.

Transient upsets from protons in high-speed optocouplers were investigated over a range of incident angles and energies. At energies below 50 MeV, very large increases in cross section occurred at angles above 60 [degrees], consistent with the increase in cross section that is expected when direct proton ionization begins to contribute to the cross section. The angular dependence of the cross section increases the number of transient upsets expected in orbit compared to upset rate calculations that do not take the angular dependence into account. Laboratory alpha particle measurements were used to measure critical charge in these devices. The critical charge and area of the photodiode provide a way to identify devices that are sensitive to direct ionization at large angles.