200V through 10K what a waste,
> For your engineering laugh for the day... or maybe sadness, depending
> on your point of view, see page 65-66 (Ideas for Design) of the
> October 9 edition of Electronic "Design" Magazine.
>
> Sheeeeesh!
putting 1K to 12V should have been enough,
I guess it's possible he was working with a damaged TL431 :)
...Jim Thompson
The K is ALWAYS lower case for the kilo designation.
Back then, they weren't into efficiency as much.
The K is ALWAYS lower case for the kilo designation.
Does the schematic in your copy actually say that the voltage source at the top of R2 is 200V? The copy I just got from the link provided has it as 20.0V.
Oh, and when the 431 is turned on, there would be 199V across 10k which would dissipate 3.96 watts.
That's one "advantage" of print, everyone gets all the same goofs. With websites and pdf's, such things can be edited and reloaded in no time. Perhaps someone at E"D" (hmm, seems I've heard E.D. as meaning something else...) has been informed of this thread.
Big Brother would LOVE The Internet! ;)
"Jasen Betts" schreef in bericht news:gdcaf2$9v0$ snipped-for-privacy@reversiblemaps.ath.cx...
I doubt I'd read the issue if Jim didn't point to it and I'm sure had not give the articles a second glance. Now I looked at the first one and found both solutions Jim mentioned though not within 10s. I had to find the TL431 datasheet and read it to know what the beast was supposed to do anyhow. IMHO this TL431 is not the right circuit for the purpose mentioned. I'd use some simple comparator for it. Nevertheles, if you're building a one of and have the TL431 at your hands, why not use it? The same applies for the "solution". If the 20.0V (not 200V as you'd blow the TL431) is available why not use it? As an example of "circuit design" I can neither laugh nor cry about it. It's simply not interesting and I wonder why Jim mentioned it. Maybe he's growing old? :)
As for the second "design idea" I did not even start to read it (except for the title that is.)
petrus bitbyter
my bad
How things have changed this past week!
Bye. Jasen
oh yeah, if I zoom it to 200% the point is clearly visible, why do they write 20.0 when they mean 20?
I'm reading the PDF.
Bye. Jasen
The generic reason is to denote tolerance.
It's not an exemplary circuit.
As each day passes YOU are one day closer to death ;-)
...Jim Thompson
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