Technical Reference
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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 Telcordia SR-332
Issue 2, Method I, Case 3, 55 ºC ambient. The MTBF prediction is used to estimate
repair rates and spare parts requirements. The MTBF for the board is 69,840 hours.
2.8 Environmental
Table 21 lists the environmental specifications for the board.
Table 21. Environmental Specifications
Parameter Specification
Temperature
Non-Operating
-40 °C to +60 °C
Operating
0 °C to +50 °C
Unpackaged 50 g trapezoidal waveform
Velocity change of 170 inches/s²
Packaged Half sine 2 millisecond
Product Weight (pounds) Free Fall (inches) Velocity Change (inches/s²)
<20 36 167
21-40 30 152
41-80 24 136
81-100 18 118
Vibration
Unpackaged 5 Hz to 20 Hz: 0.01 g² Hz sloping up to 0.02 g² Hz
20 Hz to 500 Hz: 0.02 g² Hz (flat)
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