Sign in with
Sign up | Sign in
Your question
Solved

How to figure out input polarity of DC-to-DC converter?

Last response: in Components
Share
August 11, 2012 6:38:49 PM

Hello,

I recently pickup up a Migrus C4-CT-DC150L DC-to-DC converter to replace a blown converter in my mini-ITX system. However, the board didn't come with any instructions or obvious markings to indicate the input polarity. Any tips on how to figure it out?

Best solution

a b ) Power supply
August 11, 2012 8:32:31 PM

the negative pin of the input would also be system ground so check for continuity to ground elsewhere, like one of the grounds on the 20 pin motherbd connector.
Share
Related resources
August 12, 2012 9:44:25 PM

popatim said:
the negative pin of the input would also be system ground so check for continuity to ground elsewhere, like one of the grounds on the 20 pin motherbd connector.


Right, followed this advice, hooked up the 19v input (no smoke!), and tested the voltages on the 20-pin connector. Result: pins 9 and 14 show 5v from ground (I used pin 3), all others dead. Is it possible I just have it backwards? how risky is it to just test that theory?
m
0
l
a b ) Power supply
August 12, 2012 11:33:22 PM

Nope you have it perfect.
Pin 9 is the power supplys standby 5v which is always present, well should be. LoL
and pin 14 is the PS_On signal. When you press the power button on your case, the motherbd would pull this signal low to turn on the power supply. You can test this dc-dc bd by grounding that pin14 to 13 or 15 right next to it. And then you will be able to test the other voltages.
m
0
l
August 13, 2012 1:29:22 AM

popatim said:
Nope you have it perfect.
Pin 9 is the power supplys standby 5v which is always present, well should be. LoL
and pin 14 is the PS_On signal. When you press the power button on your case, the motherbd would pull this signal low to turn on the power supply. You can test this dc-dc bd by grounding that pin14 to 13 or 15 right next to it. And then you will be able to test the other voltages.


Brilliant! Yes, works perfectly now, and I've even learned a few things along the way... many thanks.
m
0
l
August 13, 2012 1:30:39 AM

Best answer selected by alecwood77.
m
0
l
!