Voltage Regulator Module (VRM) and Enterprise Voltage Regulator-Down (EVRD) 10.0 Design Guidelines

VRM and EVRD 10.0 Design Guidelines
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8.6 Electrostatic Discharge PROPOSED
Testing shall be in accordance with IEC 61000-4-2.
Operating: 15 kV initialization level. The direct ESD event shall cause no out-of-regulation
conditions – including overshoot, undershoot and nuisance trips of over-voltage protection, over-
current protection, or remote shutdown circuitry.
Non-operating: 25 kV initialization level. The direct ESD event shall not cause damage to the
VRM circuitry.
8.7 Shock and Vibration PROPOSED
The shock and vibration tests should be applied at the baseboard level. The VRM should not be
damaged and the interconnect integrity not compromised during:
• A shock of 30 g with an 11-ms half sine wave, non-operating, to be applied in each of
the orthogonal axes.
• Vibration of 0.01 g² per Hz at 5 Hz, sloping to 0.02 g² per Hz at 20 Hz and maintaining
0.02 g² per Hz from 20 Hz to 500 Hz, non-operating, applied in each of the orthogonal
axes.
8.8 Electromagnetic Compatibility PROPOSED
Design, including materials, should be consistent with the manufacture of units that comply with
the limits of FCC Class B and CISPR22 Class B for radiated emissions.
8.9 Reliability PROPOSED
Design, including materials, should be consistent with the manufacture of units with a Mean Time
Between Failure (MTBF) of 500,000 hours of continuous operation at 55 °C, maximum outputs
load, and worst case line, while meeting specified requirements. MTBF should be calculated in
accordance with MIL-STD-217F or Bellcore*.
8.10 Safety PROPOSED
The voltage regulator is to be UL Recognized to standard UL1950 3rd Ed., including
requirements of IEC950 and EN 60950. Plastic parts and printed wiring board are to be UL
Recognized with 94V-0 flame class.