DC-DC's total ionizing dose hardness decrease in passive reserve mode

The usual and effective way to increase on-board electronics reliability and general radiation hardness is the usage of “sleeping” (shutdown) mode and “passive” reserve of vulnerable blocks and elements. This work presents the comparative radiation test results of hybrid and integrated DC-DC converter's TID's sensitivity in active, sleeping and passive modes. The obtained experimental data demonstrates that TID hardness of bipolar, BiCMOS and hybrid DC-DCs in the unbiased condition is at least not higher than their normally biased mode. Moreover some of bipolar integrated DC-DCs have relatively higher radiation-induced degradation while unbiased, so their “passive” (so-called “cold”) reserve mode may be the worst case mode for TID's hardness level.