Greetings, group. I just got a board plopped on my bench with diodes from
a manufacturer I don't recognize. Logo is "DW" inside an ellipse,
with the "D" sans-serif upper-case and the "W" script upper-case.
Anyone recognize that?

I'm tempted to guess Daewoo, but their logo is completely different.

Oh, and the part has part number DUF860. Googling this gives 2000
hits, none relevant. Googling (DUF860 diode) gives nothing.

Package is TO-220 with chopped-short center pin, and diode symbol
printed under part number with cathode on left.

I've looked at 5 different "logos" sites, but no match. Stumped.

--
Robbie Hatley
lonewolf [at] well [dot] com

"Robbie Hatley" wrote in message
...

Greetings, group. I just got a board plopped on my bench with diodes from
a manufacturer I don't recognize. Logo is "DW" inside an ellipse,
with the "D" sans-serif upper-case and the "W" script upper-case.
Anyone recognize that?

I'm tempted to guess Daewoo, but their logo is completely different.

Oh, and the part has part number DUF860. Googling this gives 2000
hits, none relevant. Googling (DUF860 diode) gives nothing.

Package is TO-220 with chopped-short center pin, and diode symbol
printed under part number with cathode on left.

I've looked at 5 different "logos" sites, but no match. Stumped.

--


http://pdf1.alldatasheet.com/datashe...EMI/UF860.html


Might be close or the same.

"tm" writes:

http://pdf1.alldatasheet.com/datashe...EMI/UF860.html

Might be close or the same.

That's just a search page, and it returns no actual hits for a "Microsemi UF860"
(assuming that such a part even exists, which is doubtful). It's just a generated
(failed) search attempt from a previous user, not an actual source of information.
(Hint: all the websites with "datasheet" in their name are advertising for
unrelated junk. Best to filter those out of your google searches, they just waste
time.)

Googling just "UF860" yields:
http://www.sensitron.com/RecDie.pdf
which has an xref chart stating that a good xref for "UF860" (manu unspecified)
is "Microsemi SD120UF600X60". However, I see no evidence on the web or
on vendor web sites (eg, Digikey) of the existence of such a part.

Good guess that "DUF860" stands for "Diode, Ultra-Fast-recovery".
The "8" and "6" might indicate 80A, 600V or 60A, 800V. Or they may
have no meaning whatsoever, and the actual values could be
10A @ 900V or 35A @ 150V or whatever.

Looks like I'm going to have to intuit from reverse-engineering what the
current and voltage ratings are, unless I can find what company "DW" is
and get the data sheet from their web site. (Once I find the V/I ratings,
easy enough to get suitable replacement from Vishay or whoever.)

Hence the original question:

Who has logo "DW" in ellipse, D upper-case sans-serif, W upper-case script?

--
Robbie Hatley
lonewolf [at] well [dot] com

"Robbie Hatley" wrote:
Greetings, group. I just got a board plopped on my bench with diodes from
a manufacturer I don't recognize. Logo is "DW" inside an ellipse,
with the "D" sans-serif upper-case and the "W" script upper-case.
Anyone recognize that?

I'm tempted to guess Daewoo, but their logo is completely different.

Oh, and the part has part number DUF860. Googling this gives 2000
hits, none relevant. Googling (DUF860 diode) gives nothing.

Package is TO-220 with chopped-short center pin, and diode symbol
printed under part number with cathode on left.

I've looked at 5 different "logos" sites, but no match. Stumped.


MUR860. ??

Greg

I would suspect it's house marked. The MUR860 looks alot like your
description :

http://www.fairchildsemi.com/ds/RU%2FRURP860.pdf

Like they have the MUR and RURP, but there appears to be no difference
at all. Sometimes it's an insulated tab, providing it's metal, or may
indicate an all plastic case, but it doesn't say so here. The P really
does seem like it should mean plastic case but it is not on the
datasheet so I assume not.

Actually I have dispensed with dealing with most part numbers. You can
get half an idea what frequency it runs at, then the output filter on
that leg of the power supply can give you the approximate voltage.
Also, the value of the filter can allude to the approximate current
drain on the leg. Something pulling 3mA does not quite warrant an
8.600 uf......

All in all, if you're looking or a manufacturer out of curiousity that
is one thing, not that you'll find it. It's like Sharp taking an IC
and having it labelled RihX-4462-01ceZZ* when it is a friggin LM356.
Or Samsung with their KA numbers. (*that is not a real number, I just
made it up)

Reverse engineering is your friend. Look at the link real quick and
look at the circuit, most likely you have a replacement in an MUR, if
not I can find diodes that can replace almost ANYTHING in a TO220
case. Can't say zzactly what they might cost..........

J

"Jeff Urban" writes:

I would suspect it's house marked...

Yes, that would explain it. Some reseller brand. Like, buying a bike
marked "Schiwin"... but they haven't actually *made* bikes in decades,
it's actually some damn company in Taiwan, Korea, or China,
named "Kwang Lu Chin" or some such thing.

...The MUR860 looks alot like your description :

http://www.fairchildsemi.com/ds/RU%2FRURP860.pdf

8A 600V? Yep, that sounds very reasonable. (This circuit uses
+400VDC power supply, pulsed through MOSFETs to an eddy current
brake, to provide braking in a mechanical system. One of the mystery
diodes is used with cathode to switch point and anode to ground, to
eat the negative inductive spikes each time the MOSFETs turn off.)

And on looking at some data sheets, seems that "860" in diode part numbers
generally does mean 8A 600V.

... I can find diodes that can replace almost ANYTHING in a TO220
case...

These days, seems most of the world's electronics are made by Vishay
(China). Plus side, any parts you want, cheap. Down side, all the mfg jobs
are now in China. (Communist worker drones, $0.65/hr, 16hr/day, 6 days/wk.
American workers can compete with that. The phrase "Silicon Valley"
now means Shenzhen, Guang Dong, China. Sigh.)

... Can't say zzactly what they might cost ...

Prolly about a buck.

Anyway, thanks for the insiteful response, I think I have a handle
on what these diodes are now.

--
Cheers,
Robbie Hatley
lonewolf [at] well [dot] com

"gregz" sez:

MUR860 [is xref for DW DUF860] ??

Yep, seems so. (See my reply to Jeff Urban.) Thanks for the reply.

--
Cheers,
Robbie Hatley
lonewolf [at] well [dot] com

On Mon, 2 Apr 2012 16:10:46 -0700, "Robbie Hatley"
put finger to keyboard and composed:

"tm" writes:

http://pdf1.alldatasheet.com/datashe...EMI/UF860.html

Might be close or the same.

That's just a search page, and it returns no actual hits for a "Microsemi UF860"
(assuming that such a part even exists, which is doubtful).

Microsemi Ultra Fast Recovery Rectifiers, UF860 - UF880:
http://www.datasheetarchive.com/dl/D...DSA-369439.pdf

Package similar to TO-220AC
UF860 -- 8A, 600V
trr - 70ns max

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.