Power Connectors - DFI COM331-B User Manual

2
Hardware Installation

Power Connectors

Use a power supply that complies with the ATX12V Power Supply Design Guide
Version 1.1. An ATX12V power supply unit has a standard 24-pin ATX main
power connector that must be inserted into the 24-pin connector. The 4-pin +12V
power connector enables the delivery of more +12VDC current to the COM ex-
press module board and carrier board's PCIe device.
The power connectors from the power supply unit are designed to fi t the 24-pin
and 4-pin connectors in only one orientation. Make sure to fi nd the proper orien-
tation before plugging the connectors.
Important
The system board consumes a minimal amount of power. Due to its low
power consumption, you only need a 120W to 150W power supply. Every
power supply has its minimum load of power. If you use a greater than
150W power supply, the power consumed by the system board may not
attain its minimum load causing instability to the entire system.
40
13 1
+3.3VDC
COM
+5VDC +12VDC
+5VDC +12VDC
+5VDC
+5VSB
NC
PWR_OK
COM COM
COM
+5VDC
COM
COM
PS_ON# +5VDC
COM
COM
+3.3VDC
-12VDC
+3.3VDC
+3.3VDC
12
24
4 2
+12V
Ground
+12V
3 1
Ground