Circuit help

AWhackWhiteBoy

Golden Member
Mar 3, 2004
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I grabbed a CCFL from an old laptop with the hopes of reusing it to light up my case, toss in a switch, hook it up to a molex connector, and i'll have a nice light when working in my PC.

the CCFL and inverter PCB in question

Anyhow, the Cotek website offers an array of different models and their specifications,however none match mine. it seems that it might be a custom model for this application.

their inverters

it appears that most are 5v and 12v, 12volts would be ideal for me but i'm afraid to hook anything up to this before knowing its abilities.

how would i go about figuring this out? the only parts with a label is the capacitor, which is 47uF and 50v, and the resistor which is 6800 ohms +/- 5%. the transformer only has jibberish on it. i know this is very little help but any input would be appreciated.

edit: i have a small Fluke DMM nearby if that helps.
 

PottedMeat

Lifer
Apr 17, 2002
12,363
475
126
so you tore out the CCFL + Inverter board out of a laptop and are unsure of what voltage to hook it up to?

note: i dont know what voltages laptops use to power their inverter boards
maybe its something different like +9 or soemthing.

if there arent any identifying marks on the bottom of the board, id go ahead and try +5V to power it and see how the brightness is. If it seems too dim, try +12 volts.

why is +12 preferable to you? You can get +12 (yellow + black wires) or +5 (red + black) on any molex hdd connector.
 

AWhackWhiteBoy

Golden Member
Mar 3, 2004
1,807
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because i happen to have a molex to 3 pin fan adapter infront of me with wires already hooked up to the 12v line, all i have to do is cut off the 3pin end and hook it up :)

edit: apparently, 5 or 12volts isn't even enough....

any other suggestions?
 

Mday

Lifer
Oct 14, 1999
18,647
1
81
have you bothered checking the specifications for the inverter on that board?
 

Mday

Lifer
Oct 14, 1999
18,647
1
81
Originally posted by: AWhackWhiteBoy
if i knew which part on the PCB was the "inverter" i probably would

the big yellow thing o_O with the coils and the writing i cant read cuz of the bad angle of the picture (not referring to the chinese on top).

-

correction... since i was half asleep at the time

the stuff on the board are components of a circuit that inverts (DC -> AC) the yellow thing is a transformer. it should have some info on it.
 

Mark R

Diamond Member
Oct 9, 1999
8,513
16
81
No way to tell based on the info you've given us. Looking at the components on the board won't be helpful. The transformer will be custom-made and just have a part number code on it - nothing useful.

If you can't get the specs on the inverter board from the manufacturer then you're not going to find out from anyone else.

Is there anything on the laptop motherboard that might suggest what voltage it gives to the inverter? Does the laptop work enough for you to probe with your DMM to find out?

Failing that, it probably is 5V - but then only way to know is to try it. If it works, it works. If it sizzles, too bad. It could be 12V, but I'd try 5V first.
 

Cruisin1

Golden Member
Oct 10, 1999
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Yeah you pretty much need the specs on the inverter. Typically though inverters for CCFL lights take in +5V... but be WARNED! they can output very high AC voltage (~255VAC). I've had a few incidents touching this active end.... and it sure gave me a HELL of a shock along witht the smell of burnt skin :(
 

mobobuff

Lifer
Apr 5, 2004
11,099
1
81
Eh? Laptop? That looks a lot more like a CCFL from a flatbed scanner, judging from the setup of the inverter and the photosensitive pick-up device that the right end of the tube is laying on.

In any case, be careful with the tube, they break (or pop) very easily.