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From: DaveC on 27 May 2010 15:24
I've never had to look up a SMD semi before now. Unlike JEDEC codes, these
less-than-brief alphanumeric codes have no standard that I can find.

And if there's no manufacturer mark (or it has become illegible), there's no
hope of finding a replacement.

In my case:
HFJ (the "J" is smaller than the others), 3 terminal, SOT-23 size.

I'm speaking, of course, of a circuit that has no schematic available for it.


Is there a device code data base? Maybe I just missed it in my Yahooing?

Thanks.

From: Meat Plow on 27 May 2010 15:36
On Thu, 27 May 2010 12:24:36 -0700, DaveC wrote:

> I've never had to look up a SMD semi before now. Unlike JEDEC codes,
> these less-than-brief alphanumeric codes have no standard that I can
> find.
>
> And if there's no manufacturer mark (or it has become illegible),
> there's no hope of finding a replacement.
>
> In my case:
> HFJ (the "J" is smaller than the others), 3 terminal, SOT-23 size.
>
> I'm speaking, of course, of a circuit that has no schematic available
> for it.
>
>
> Is there a device code data base? Maybe I just missed it in my Yahooing?
>
> Thanks.

http://www.marsport.org.uk/smd/
From: DaveC on 27 May 2010 23:35
> http://www.marsport.org.uk/smd/

No "HFJ" listings.

Thanks,
Dave

From: Franc Zabkar on 28 May 2010 02:46
On Thu, 27 May 2010 12:24:36 -0700, DaveC <invalid(a)invalid.net> put
finger to keyboard and composed:

>I've never had to look up a SMD semi before now. Unlike JEDEC codes, these
>less-than-brief alphanumeric codes have no standard that I can find.
>
>And if there's no manufacturer mark (or it has become illegible), there's no
>hope of finding a replacement.
>
>In my case:
>HFJ (the "J" is smaller than the others), 3 terminal, SOT-23 size.
>
>I'm speaking, of course, of a circuit that has no schematic available for it.
>
>
>Is there a device code data base? Maybe I just missed it in my Yahooing?
>
>Thanks.

FWIW, a "HF" marking code identifies a Toshiba 2SC3124 NPN transistor,
15V, 50mA, for TV Tuner, VHF Oscillator Applications:

http://www.datasheetcatalog.org/datasheet/toshiba/1264.pdf

The lowercase "j" may be unrelated to the part number.

For example, a Philips BCW89 transistor has a marking code of H3*,
where *=p for "Made in Hong Kong", or *=t for "Made in Malaysia".

http://www.nxp.com/documents/data_sheet/BCW89.pdf

You may be able to discern the manufacturer, or country of origin,
from the surrounding components. The function of the device may be
deduced from the circuit itself. For example, is the board part of a
tuner?

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
From: N_Cook on 28 May 2010 03:26
DaveC <invalid(a)invalid.net> wrote in message
news:0001HW.C824150402789DE5B01AD9AF(a)news.eternal-september.org...
> I've never had to look up a SMD semi before now. Unlike JEDEC codes, these
> less-than-brief alphanumeric codes have no standard that I can find.
>
> And if there's no manufacturer mark (or it has become illegible), there's
no
> hope of finding a replacement.
>
> In my case:
> HFJ (the "J" is smaller than the others), 3 terminal, SOT-23 size.
>
> I'm speaking, of course, of a circuit that has no schematic available for
it.
>
>
> Is there a device code data base? Maybe I just missed it in my Yahooing?
>
> Thanks.
>

some more sources
http://www.satcure-focus.com/design/page2.htm
http://www.schematicsforfree.com/archive/file/COMPONENTS/SMD%20Codebook.pdf
http://clivetec.superihost.com/SMD_CodesT.htm

"part marking", "top code", "topcode" ,"top mark", "topmark" ,"marking" as
synonym adjunct keywords for SMD device coding via Google
along with "datasheet" or "data" if many irrelevant returns eg searching for
SMD topmark D132 data , then
("D132" AND "datasheet" "top code" OR "topcode" OR "top mark" OR "topmark"
OR "marking" OR "part marking" )
entered into the searchbox. Or ("D132" AND "filetype:pdf" "top code" OR
"topcode" OR "top mark" OR "topmark"
OR "marking" OR "part marking" ) limiting to trade pdf sources only.
Any more synonyms gratefully received.
Or best search engine for picking up letter pairs / triplets, google not too
good for this
Or anyone know of a replacement for this , in its time very useful NEAR
function for Google searches?
http://www.staggernation.com/cgi-bin/gaps.cgi
ie in this case "marking" NEAR "D132" within 1 , 2 or 3 words that order or
each way , selectable


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://diverse.4mg.com/index.htm




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