Power Supply Connectors

Connectors Index:

* ATX Power Supply Connector

[ Interfacing index]

ATX Power Supply Connector

20 Pin, MOLEX, 4.2mm pitch
Part No. 39-29-9202, male, PCB mounting
Part No. 39-01-2200, female, cable mounting.

ATX Power Supply Connector

Pin Color Signal  

Signal Pin Color
11 Orange 3.3V 3.3V 1 Orange
12 Blue -12V 3.3V 2 Orange
13 BlackCommon Common 3 Black
14* Green PS-On 5V 4 Red
15 Black Common Common 5 Black
16 Black Common 5V 6 Red
17 Black Common Common 7 Black
18 White -5V Pw-OK 8 Grey
19 Red 5V 5V Standby 9 Purple
20 Red 5V +12V 10 Yellow

* Pin 14 has an internal pull-up to +5V.
When pin 14 is grounded the power unit will come out of standby and into full operation.

Maximum supply currents for 250W ATX PSU , with power at Imax.
Sig.Name Current Power
+3.3V 14A 46.2W
+5V 25A 125W
+12V 10A 120W
-5V 0.5A 2.5W
-12V 0.8A 9.6W
Load limits
Sig.Name Limit
+5V and +3.3V combined 125W
-5V and -12V combined 10W
Suggested loads for testing
Sig.Name Current/
+3.3V 10 33 0.33
+5V 15.2 76 0.33
+12V 8 96 1.5
-5V 0.5A 2.5 10
-12 0.55 6.5 22
Total test load = 214W
Sig.Name Actual power
+5V and +3.3V combined 109W
-5V and -12V combined 9W
[ Power Supply Connectors Index]

Originally by:R.Clarke@surrey.ac.uk
Last modified: 2002 May 8th.
from: http://www.ee.surrey.ac.uk/Workshop/advice/conns/connPSU.html
beautified by Dennis German