MTBF Prediction for Electronic Design
The Mean Time Between Failure (MTBF) module predicts component failure rates and presents the MTBF result for each component and assembly in a system tree using a serial reliability model. Component failure rates are predicted according to the following models: Mil-HDBK-217-F2/G, Telcordia-3, IEC-62308, SN-29500 Siemens, FIDES, GJB299, HRD-4 and Rel-Tools -non-operation, including customized user dened models. Calculations can combine multiple prediction methods in a single project.
MTBF prediction can be based on data limited to the part type and count information, and then, as the design progresses, the MTBF model can be updated to include thermal and electrical stress analysis information.
BQR’s fiXtress – MTBF module uses two different methods:
Parts count – A stress level of 50% is used as default, instead of the real operational stress parameters.
Parts stress – Stress values such as Power, Volt and Current can be entered manually or can be retrieved from fiXtress- Rapid or fiXtress-Precise, and these values will be used to calculate the components failure rate based on stress.
Parts count analysis, typically conducted early in the design phase to measure the product reliability before finalization of the Bill of Materials, is a simple procedure. As opposed to the parts stress method which uses actual stress parameters, parts count analysis utilizes 50% stress as a basis for calculating the component failure rates of a design. Generally speaking, parts count analysis produces a higher component failure rate than parts stress analysis because the actual stress is typically less than 50%.
The following prediction methods are implemented in the fiXtress software for electronic design:
|MIL-HDBK-217||US Military (MIL-HDBK-217F N2) & MIL-HDBK-217G|
|Telcordia (SR-332)||Telecom products, Steady state (Version 3)|
|IEC-62380||Industrial Level especially for Telecom, based on France CNET (Version 2009)|
|HDBK GJB299||Developed by China (Version B)|
|Siemens SN-29500||For Industrial (Version 2009)|
|FIDES||Developed by FIDES Group used for Aerospace (Version 2009)|