This paper describes a top-down approach to reliability investigation of po
wer electronic systems used in terrestrial and space applications. Results
obtained from several case studies are presented that describe in detail bo
th short-term and field failures of high-power DC-DC and AC-DC converters a
nd the causes there-in. A systematic approach is presented that can be used
to correlate field failures of power converters to residual defects and co
ntaminants left in the semiconductor power switch, packaging and thermal ma
nagement. Techniques and strategies that need to be applied in developing r
obust power converters for the next millennium are also outlined. (C) 1999
Elsevier Science Ltd. All rights reserved.