Quantification of printed circuit board (PCB) connector reliability

Martin Marietta Corporation conducted a 12-month program to develop a failure rate mathematical model for printed circuit board connectors as used in military electronic equipment and conforming to the requirements of MIL-C-21097 and MIL-C-55302. This model is provided in the format of a subsection to Section 2.11 of MIL-HDBK-217B, and includes the model, instructions for its use, and limitations in its use. More than 736 million part-hours of operating field data were collected from industrial and government data sources. Data was analyzed manually and sorted by computer. Conclusions are summarized in the revised base failure rates and mathematical models described. Failure rates show a significant decrease from the present rates described in MIL-HDBK-217B. The mathematical model is described with a multiplying cyclic parameter (PI sub K) which varies in accordance with mating/unmating cycles of each connector.