Technical Reference
57
2.7 Reliability
The Mean Time Between Failures (MTBF) prediction is calculated using component and
subassembly random failure rates. The calculation is based on the Bellcore Reliability
Prediction Procedure, TR-NWT-000332, Issue 4, September 1991. The MTBF
prediction is used to estimate repair rates and spare parts requirements.
The MTBF data is calculated from predicted data at 50 ºC. The MTBF for the board is
138,157 hours.
2.8 Environmental
Table 33 lists the environmental specifications for the board.
Table 33. Environmental Specifications
Parameter Specification
Temperature
Non-Operating
-40 °C to +60 °C
Operating
0 °C to +40 °C
Shock
Unpackaged 50 g trapezoidal waveform
Velocity change of 170 inches/second²
Packaged Drop
Product Weight (pounds) Free Fall (inches) Velocity Change (inches/sec²)
<20 36 N/A
>=20 and <40 30 N/A
>=40 and <80 24 N/A
>=80 and <100 18 N/A
>=100 and <120 24 N/A
>=121 18 N/A
Vibration
Unpackaged 50 Hz to 500 Hz , 3.13G_rms random
Packaged 5 Hz to 40 Hz: 0.015 g² Hz (flat)
40 Hz to 500 Hz: 0.015 g² Hz sloping down to 0.00015 g² Hz
To Next Page
Loading...
