"Arny Krueger" wrote in message
. ..
"Trevor Wilson" wrote in message
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"Trevor Wilson" wrote in message
news:...
"ScottW" wrote in message
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Now I'm confused again....isn't all that power supply stuff
technically decoupling?
Often, a mixture.
**Of course it is. For some reason, Arny wants to argue the point. I
have no idea why. He's wrong.
Yawn.
Bypassing is shunting to ground at the source...not at the
power supply.
Bypassing has more than one meaning.
**Bypassing is a similar term, but relates to the use of a (say) film
cap
across an electro.
That's one meaning. But its not the only one.
Or, in the case of a tube amp, when the Cathode is
coupled to ground, through a resistor, which is bypassed with a
capacitor.
That's another meaning.
It gets a little muddy, however.
So much so that certain dogmatic posturing about other people being wrong
is itself wrong.
Here's a reputable app note on high speed digital
circuits which have far greater need .....
http://hsi.web.cern.ch/HSI/s-link/de...c/decouple.pdf
Here's a definition of the difference between bypassing and decoupling:
"Decoupling: The art and practice of breaking coupling between portions of
systems and circuits to ensure proper operation."
"Bypassing: The practice of adding a low-impedance path to shunt transient
energy to ground at the source. Required for proper decoupling."
Note that bypassing can provide a certain amount of decoupling, depending.
Note that were I Trevor, I might say that the given definition of
bypassing proves his definition of bypassing to be wrong. But it isn't.
Both definitions can be correct in the appropriate context.
**That particular cite is MUCH better than your earlier one. I concur
with
the description.
**Nope. I checked. ALL use electros for decoupling. Every single one.
Some have film caps as well.
Trevor is wrong again.
**Nope. Trevor is 100% correct.
I made a post this morning that provided numerous
counter-examples, based on the service manual of a receiver that Trevor
cited as proving his point. I cited page numbers and part numbers.
**I cited the OP part numbers where decoupling is used.
Well...I picked one op amp (BTW..I didn't see any obviously in the
audio circuits..only video)..and it was decoupled with a ceramic.
Decoupling circuits generally include a series element, the output end of
which is connected to a capacitor that is grounded at the other end. The
series element can be either a resistor or an inductor.
**Find it yourself. I just jumped through hoops for Arny. I'm not
doing it again. OK, ONCE. You get ONE example only. Here goes:
NAD 5000 CD player. Page 34.
IC109, IC110, IC111, IC112, IC113, IC114, IC117.
Happy?
Yes, especially since I provided numerous counter-examples from a Denon
receiver that Trevor cited.
**I cited the numbers of the OP amps where decoupling is used. I suggest you
get someone to explain schematics and how to read them to you.
Don't **** me off again.
I'm sure I did that! ;-)
**Sure. You're frustratingly obtuse.
Do your own damned legwork.
I did, and proved that Trevor was not looking at the whole picture.
I listed a bunch of models for you and Arny.
Many of which were dead ends, showing that Trevor wasn't checking his
sources.
**Cite these alleged "dead ends".
Arny can't be bothered searching for proof
Nonsense. But I know that Trevor is likely to go into denial mode.
and neither, it seems, can you.
All the other models listed have similar topologies.
Again, proof that Trevor hasn't done *his* homework.
**Incorrect. Examine all the cites I provided. I did.
Trevor Wilson