What to replace a blown voltage regulator... Cross referencing...

[Todd Nathan]

I'm trying to fix a netvista mobo that shot the bucket...
3 caps and one (I think it is a voltage regulator) blew the roost.
I'm looking for replacement information on the regulator

CET
CDB6030L
(delta)13U1A

I just need to know what item I can order or get at RadioShack
or some online seller, or find as commonly found spare on tossaway
boards (I rip apart alot of junk for fun, so maybe I can find one
on a mobo somewhere). Your help is apreciated.

NOTE, I lost 3 caps (at least visually they are the only other parts
fried) which I know the values, 1500uF at 10V, I can and will find
them, just wondering if I can replace them with higher Volt rating
caps if found and also high uF rating without damaging the mobo.
These components, the Regulator and the 3 caps make up part of the
Voltage Regulator Module on the mobo, integrated, not seperately plugged
in. I'm hoping to salvage the mobo and get this running again.

Thank you, please email me directly. The biggest issue is to find a
replacement (hopefully cheap) either from RadioShack, spare parts, or
someone like Mouser or the like for the Regulator listed above. I don't
read online USENET any more, so please email me directly. I really
appreciate your thoughts and help!

Best wishes.

 

[Dave D]

I'm trying to fix a netvista mobo that shot the bucket...
3 caps and one (I think it is a voltage regulator) blew the roost.
I'm looking for replacement information on the regulator

CET
CDB6030L
(delta)13U1A

I just need to know what item I can order or get at RadioShack
or some online seller, or find as commonly found spare on tossaway
boards (I rip apart alot of junk for fun, so maybe I can find one
on a mobo somewhere). Your help is apreciated.

NOTE, I lost 3 caps (at least visually they are the only other parts
fried) which I know the values, 1500uF at 10V, I can and will find
them, just wondering if I can replace them with higher Volt rating
caps if found and also high uF rating without damaging the mobo.
These components, the Regulator and the 3 caps make up part of the
Voltage Regulator Module on the mobo, integrated, not seperately plugged
in. I'm hoping to salvage the mobo and get this running again.

Thank you, please email me directly. The biggest issue is to find a
replacement (hopefully cheap) either from RadioShack, spare parts, or
someone like Mouser or the like for the Regulator listed above. I don't
read online USENET any more, so please email me directly. I really
appreciate your thoughts and help!

Best wishes.

I'm 99% sure that is a Mosfet, not a voltage regulator. It is used as a
switching transistor in the switchmode regulator. I'm not sure you'll find
an exact replacement easily, you might be stuck with finding a similar spec
device.

What makes you think it is faulty? Obviously if it's cracked then it is bad.
However there's other components can fail causing over voltage in these
circuits, check the Mosfet for shorts first, it may be OK. The bad
capacitors themselves may have been the fault, it's pretty common on
motherboards.

Dave

 

[Dave D]

Ok, I'm not knowledgable, but I can include an image for you to see, just
email me and I'll zap it back to you.


The legs/leads on it were melted, disconnected, and the back grounding
(assuming it is grounding) that was soldered to the mobo was burned off
and thus it was lifted off (about 2-3 mm) off the mobo. it is fried,
no question, charded mobo under it too. I figured if the caps can be
salvaged from another scrap board, and this item (whatever it is) that
was right next to the 3 caps that blew (1500uF @ 10V) and expanded, oozed
out, could be had for cheap, I can fix it myself. 1.1 Ghz cpu, IBM mobo
and components, maybe I get 'free' DVD/DivX player to go on top of TV

OK, I've looked at the photos. The Mosfet has shorted causing overvoltage on
the output of the regulator. Maybe the caps caused this, maybe the shorted
Mosfet caused the caps to go bad, who knows. One other possibility is
something downstream overstressed the Mosfet, like a bad CPU. Have you
checked the processor in another mobo?

I really think you'll have trouble sourcing that Mosfet new. You may find a
spare dead mobo with a good one, I've seen these Mosfets on countless mobos,
and subbing it, and all the faulty caps, might get you working. However, the
survival of the CPU should be checked out, and I'm not sure I'd want to put
in another CPU to test it after the repair!

BTW, I hope you cleaned that electrolyte of the mobo ASAP, it doesn't do the
traces any good!

Dave

 

[James Sweet]

MOSFETs are among the most substitution-friendly parts I've come across, I
wouldn't be surprised if some random mosfet worked just fine there, but it
would surprise me if nothing else was damaged.

 

[Todd Nathan]

OK, I've looked at the photos. The Mosfet has shorted causing overvoltage on
the output of the regulator. Maybe the caps caused this, maybe the shorted
Mosfet caused the caps to go bad, who knows. One other possibility is
something downstream overstressed the Mosfet, like a bad CPU. Have you
checked the processor in another mobo?

I have no other mobo to test the CPU, however I will look around. I
undrestand
your concerns about putting a good working CPU into a 'fixed' board to
test the
board repair. I would not do such a thing. I was told this
machine/mobo took
a good zap in a storm. I see the discoloration from the heat of the
Mosfet
around the location. Other than the discoloration I don't see any
other damage
(in the photos, things are cleaned up a bit now) other than this, no
trace
pealing or board delamination. I'm confident I can do the repairs,
whether or
not that works and I'm back running is another issue. The obvious we
look, the
not-so-obvious I am not skilled enough to know or see.

I really think you'll have trouble sourcing that Mosfet new. You may find a
spare dead mobo with a good one, I've seen these Mosfets on countless mobos,
and subbing it, and all the faulty caps, might get you working. However, the
survival of the CPU should be checked out, and I'm not sure I'd want to put
in another CPU to test it after the repair!

I'll look around, I don't know what I'm looking for, but if our other
posting
friend is correct, and Mosfets are fairly interchangable, then I just
need
to find one that works. I'm not sure what a Mosfet does, or how to
verify it works.
I have a voltage meter from Radio Shack, so if that would help, this
could get
quite easy with the correct information. BTW, the caps are 1500uF @
10V and maybe
I can find some of those on other boards. Can I safely use a higher
rated
uF and V on a replacement cap (say a 2000 or 2200uF rated at 12 or
15V?).

BTW, I hope you cleaned that electrolyte of the mobo ASAP, it doesn't do the
traces any good!

I used 99+% rubbing as soon as I found the problem, and the board is
really clean.
My concern for oxidation or errosion was also of a concern.

Dave

Thanks for all your help, and I'm glad the pictures seemed to help out
quite a bit.
The noticably visible non missing mosfet next to the one that was
burned off and
removed in the photos is IDENTICAL to the one that I removed prior to
the pictures
being taken. It was burned off, and lifted, so I figured I may as
well remove it,
then I thought to take some photos. The caps are now off, and the
board is now cleaned.
99 cents of 99% rubbing alcohol is nice price So would working
components from a
mobo or PS, something electronic and scrapped.

Todd

 

[Todd Nathan]

I would bet that a suitable replacement would be the FDB6030L from
Fairchild.

Wong

Thank you, would seem that is the same number 6030, and maybe the FDB is the
fairchild lettering? Any recommendation on sourcing Fairchild FDB6030L?
Really appreciate your help and advice. Finding caps now, do you think that
a 2000/2200 uF at 10+ volts is fine also?

[ ... stuff deleted for brevity ... ]