Power Distribution Box Requirements               Craig Dukes
-----------------------------------               January 25, 2010

Backplane:
- Busbar current limits:
  - 3.3V: 2.0A per channel,  8.0A per board, 132A per box (2AWG, 115A)
  - 24V:  1.0A  per channel, 4.0A per board,  70A per box (6AWG,  65A)
  - ground:  132A + 70A = 202A
  - Fermilab safety requires 1000A per square inch.  Hence:
      3.3V:   0.132 square inch  (1/8” x 1.056”)  Use: 1.125"
      24V:    0.070 square inch  (1/8” x 0.560”)  Use: 0.625"
      ground: 0.202 square inch  (1/8" x 1.616")  Use: 1.625"

Breakers:
- Breakers:  3.3V 100A
              24V  40A
Trace Reqiurements:

General
- No traces should overlap the card slots.
- 2oz copper should be used.
- Fuses should be as close as possible to the backplane header.
- Front panels must be connected to ground.
- Power and return traces for different voltages must be separated
  such that there are no loops to allow magnetic noise coupling.
- Current limiter components should be well away from grounds.
- Need to have the return lines on the outside of the input headers.

FEB Card:
- Text:  "NOVA PDB FEB Card        Univ. Virginia v3.1  Jan 2010"
- Current capability:
  - 3.3V: 2.0A per channel, 8.0A per card
  - 24V:  1.0A per channel, 4.0A per card

DCM Card: 
- Text:  "NOVA PDB DCM Card        Univ. Virginia v3.1  Jan 2010"
- Current capability:
  - FEB power:
    - 3.3V: 2.0A per channel, 4.0A per card
    - 24V:  1.0A per channel, 2.0A per card
  - DCM power:
    - 24V:  6.0A for the DCM output

Indicator Card:
- Text:  "NOVA PDB Indicator Card  Univ. Virginia v3.1  Jan 2010"

Backplane:
- Text:  "NOVA PDB Backplane       Univ. Virginia v3.1  Jan 2010"
- Keyed DCM card