RadiSys ATCA-5400 RTM, Reference

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A
Mean time between failures (MTBF)
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Mean time between failures (MTBF)

Calculation Type: MTBF/FIT rate

Standard: Telcordia Standard SR-332 Issue 2

Methods: Method I, Case III, Quality Level II
The calculation results in Table 12 were generated using the references and assumptions listed.
This specification and its associated calculations supersede all other released mean time
between failures (MTBF) and failure in time (FIT) calculations with earlier dates. The reported
failure rates do not represent catastrophic failure.
Environmental assumptions

Failure rates are based on a 35°C ambient temperature.

Applied component stress levels are 50% (voltage, current, and/or power).

Ground, fixed, controlled environment with an environmental adjustment factor equal to
1.0.
General assumptions

Component failure rates are constant.

Board-to-system interconnects are included within estimates.

A hard disk drive is not included in estimates.

Non-electrical components (screws, mechanical latches, labels, covers, etc.) are not
included in estimates.
General notes

Method I, Case I = Based on parts count. Equipment failure is estimated by totaling device
failures rates and quantities used.

Quality Level II = Devices purchased to specifications, qualified devices, vendor lot-to-lot
controls for AQLs and DPMs.
Where available, direct component supplier predictions or actual FIT rates have been used.
Table 12. Reliability estimate data
MTBF at 35°C Failure rate (FIT) at 35°C
733,000 hours
1364 per 10 9 hours