MFCC-ODIN Power supply issues

22 June 2000 - Discussion Erik van der Bij with Michel Chorowitz, CES

The RIO2 3V3 supply can deliver 7 A of current. The RIO2 needs itself 4 A of this.
This leaves 3 A for both PMC slots.

One MFCC core (8441E or F) consumes 1.1 A.
With one MFCC, this leaves 1.9 A for the nose.
With two MFCCs, this leaves 0.4 A per nose.

If needed, a RIO2 can be modified to "boost" the 3V3 power supply.
The RIO3 (three) will be able to supply more current.
When a PEB (PMC Extender Board) is used, there is no problem as that one has a more powerful 3V3 generator.

The conclusion from this discussion was that the MFCC-ODIN nose may run from the 3V3 supply only and does not need it's own 3V3 generator (out of 5 V or 12 V). Only a RIO2 with both slots populated may give problems, but they may be removed with a modification to "boost" the 3V3 supply.

Calculation of power needed (from datasheets):
380 mA
fibre-optic transceiver
135 mA
crystal oscillator
15 mA
15 mA
Total (from datasheets, actual value is likely to be lower)
545 mA

CERN - High Speed Interconnect - S-LINK
Erik van der Bij - 11 July 2000