Auxiliary Power; Table 10-2. Atx Power Signals-J34; Figure 10-2. Atx Power Supply Connector-J34 - IBM PPC750FX User Manual

Preliminary

10.1 Auxiliary Power

The board is equipped with a standard ATX power connector. This allows the board to be externally powered
from a standard ATX power supply when it is not installed in a PCI slot.
Note: If the board is plugged into a PCI slot, the external ATX power supply will not activate under any
conditions, and pressing the ATX power-on pushbutton (U53) will have no effect.
Figure 10-2. ATX Power Supply Connector—J34
Table 10-2. ATX Power Signals—J34
Pin Name
1 +3.3V
2 +3.3V
3 GND
4 +5V
5 GND
6 +5V
7 GND
8 Power OK
9 +5V SB
10 +12V
11 +3.3V
12 -12V
13 GND
14 PS-ON
15 GND
16 GND
17 GND
18 -5V
19 +5V
20 +5V
750FXebm_ch10.fm
June 10, 2003
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11 12 13 14 15 16
Tolerance ± 4%
Tolerance ± 4%
Tolerance ± 5%
Tolerance ± 5%
Active high indicator that +5V and +3.3V are above their undervoltage thresholds
Standby power, at least 10 mA, tolerance ± 5%
Not used
Tolerance ± 4%. Remote 3.3V sense.
Not used
Active low signal that turns on the ATX power supply.
Not used
Tolerance ± 5%
Tolerance ± 5%
PPC750FX Evaluation Board
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Comment
Evaluation Board Manual
Connectors
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