A new approach to immunity testing

The need of performing immunity tests with the aim of meeting the functional safety requirements is addressed proposing an approach based upon the statistical data processing of test results, which allows to determine the susceptibility threshold of the device under test (DUT) and its safety margin intended as the distance between the actual DUT performance in the presence of the susceptibility signal and the susceptibility threshold. This represents a clear improvement with respect to the present situation of EMC standards based upon simple qualitative checks, which do not offer any warranty of safety because it is not clear how far the DUT is from its susceptibility threshold: even if the device under test is declared to be immune in normal operative conditions it may happen that a simple environmental effect such as temperature variation has catastrophic consequences.