Service manual

System Overview 1-65
The power module converts 48 VDC to the following required outputs:
• +3.3V at 135 amps
• +2.5V at 45 amps
The 2.5V is used by SRAMs that make up CPU backup cache and will be used
when such DIMMs are placed in the directory and memory modules.
The 3.3V is current-shared with the 3.3V output from the main power module.
Separate converters, some in parallel, on the module put out each voltage.
Figure 1–28 shows the block diagram of the auxiliary power module and its
daughtercard that contains the logic for the converters.
LEDs
CONV3 Overtemp
(yellow)
On
Off (normal)
If overtemp condition for converter 3
If temp OK at converter 3 in location E1
CONV2 Overtemp
(yellow)
On
Off (normal)
If overtemp condition for converter 2
If temp OK at converter 2 in location E6
CONV1 Overtemp
(yellow)
On
Off (normal)
If overtemp condition for converter 1
If temp OK at converter 1 in location E13
CONV0 Overtemp
(yellow)
On
Off (normal)
If overtemp condition for converter 0
If temp OK at converter 0 in location E12
Vaux Present
(green)
On (normal)
Off
Vaux present at the module
Vaux not present
Swap OK (yellow) On
Off (normal)
OK to swap out the module (Vaux OK LED
may be on also)
The module is not ready to swap out
Module OK
(green)
On (normal)
Off
All voltages on the module are within
tolerances
At least one voltage is out of tolerance