Q&A(FAQ) What is MTBF?
MTBF is commonly used as one of the indicators for understanding the frequency of failures.
MTBF (Mean Time Between Failures) refers to the average time between one failure and the next in products that are repaired and then returned to service(repair time is not included).
Failure rate： When the failure rate λ is constant, the reliability during the constant-failure-rate period follows an exponential distribution.
R(t) = e-λt
In this case, MTBF is the reciprocal of the failure rate.
MTBF = 1 / λ
At COSEL, MTBF is calculated based on the reliability prediction standard for DC-regulated power supplies using the part-count method, established by the EIAJ (Electronic Industries Association of Japan)
This standard conforms to the part-count methodology of MIL-HDBK-217D and defines failure rates for each component type.
EIAJ standard No. RCR-9102