If you received this by BCC and are not usually "electronics
interested" you may find the exercise worthwhile for other reasons.

The following exercise is quick to attempt, at least a little "fun",
and a sobering demonstration that what you think you see may not be
what you think you get with electronic components from sources with
less than bulletproof provenance.

Either read below for background or just start at 1. below.

When looking at an Asian data sheet that has suspect specs I often
find that by selecting a phrase from it that is liable to be unique
and doing a web search for the phrase, I can locate the datasheet or
sheets that were used as the original source. In some cases the
datasheet has clearly been used as a template but the data is
different enough that it may be valid. In other cases it can be clear
that copying of both format and data has been done and the "datasheet"
is simply a makeup and has no technical merit.

I was looking at the datasheet of an LED of suspect provenance that
had been proposed as an alternative by a supplier. While it was clear
that the LED was not a suitable replacement regardless, I decided to
check the datasheet's consistency and dumb-copying level.

I chose the search string:

     "Customer must apply resistors for protection ,
      otherwise slight voltage shift will cause big current
      change(Burn out will happen)."

This is a simplistic but sensible enough statement about the need to
manage LED current properly, but the way of saying it seemed liable to
be unique enough and quaint enough that it would only occur if cut and
pasted.

So..

1. FIRSTLY decide how many discrete instances (say, different
manufacturers) you may find for this phrase from an LED data sheet and
how many total Gargoyle hits you may expect.
  Phrase is:

             Customer must apply resistors for protection , otherwise
slight voltage shift will cause big current change(Burn out will
happen).

  Don't enclose in quotes.

2. Gargoyle it.


3. Marvel
     Count the discrete "manufacturers". [Data sheet sites will
obviously increase the number of instances but there are many many
"brands" involved.
      Gargoyle probably considers "burn out" and "burnout" as the
same. Both occur.


Searching without quotes turns up several close matches which are
obviously from the same source.
I consider the portions

               "slight voltage shift"
               "cause big current change" and
               "(burn out will happen)"

occurring together are proof enough of plagiarism.

Copying parts of a datasheet (whether written in quaint English or
not)  does NOT mean that the data is invalid, but it should sound
warnings.

Very surprisingly, even Vishay use the phrases
(http://www.vishay.com/docs/81564/temd1000.pdf) even though I would be
most surprised if they were the originators!.

Note that actual LED styles involved vary widely.

Everlight / Everchips may be the source.?


        Russell
--=20
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.