Mad_K said:
Sorry, Mad_K. I was joking about the comment analog_sa made with regards to that the datasheet does not endorse the recommendation I made to move more caps after the regulator.
I agree with the TNT design.
HE'S A JOKER...
Hi,
Well, you shouldn't for Analog_sa is right and, no joking here, so is the datasheet.
If you exceed the maximum allowed capacitance after the regulator it won't regulate anymore...it just can't because the caps become the dominant source of energy, not the reg., see?
The danger zone lies somewhere inbetween, as I'm sure you realise.
Cheers,😉
Hi,
Well, you shouldn't for Analog_sa is right and, no joking here, so is the datasheet.
If you exceed the maximum allowed capacitance after the regulator it won't regulate anymore...it just can't because the caps become the dominant source of energy, not the reg., see?
The danger zone lies somewhere inbetween, as I'm sure you realise.
Cheers,😉
On "the datesheet doesn't even endorse it" thing, I just checked LM317 datasheet on national's site.
The cap (0.1u) before the regulator is needed if the regulator is more than 6-inch away from the filter cap.
the caps after the regulator are optional - they "improves transient response. Output capacitors in the range of 1uf to 1000uf of aluminum or tantalum electrolytic are commonly used to provide improved output impedance and rejection of transients."
FYI.
The cap (0.1u) before the regulator is needed if the regulator is more than 6-inch away from the filter cap.
the caps after the regulator are optional - they "improves transient response. Output capacitors in the range of 1uf to 1000uf of aluminum or tantalum electrolytic are commonly used to provide improved output impedance and rejection of transients."
FYI.
Hi,
And which one would have the faster transient response?
The 1µF cap or the 1000µF one in this situation?
All else being kept equal of course.
Cheers,😉
And which one would have the faster transient response?
The 1µF cap or the 1000µF one in this situation?
All else being kept equal of course.
Cheers,😉
fdegrove said:
wouldn't they have the same transient response (if all else is truly kept equal) for small current drains and the larger one will have better transient response for heavier current drains.
That is my final answer, 🙂
It's worthwhile to look at Bob Pease's wonderful little book. There's a nice analysis of capacitor effects on three-pin adjustable regulators.
What it is ain't exactly clear
HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA.....
I haven't seen this much nonsense, bluffing, and utter confusion since Grey R. was posting.... I was going to make some comments but I wouldn't dream of breaking up the shear entertainment! I may have to dig out my Three Stooges DVD just to get back to something slightly coherent. I can hardly wait for AWL to see this thread.
"There's battle lines being drawn
Nobody's right if everybody's wrong
Young people speaking their minds
Getting so much resistance from behind*
I think it's time we stop, hey, what's that sound
Everybody look what's going down"
*and capacitance from in front and behind...
HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA.....
I haven't seen this much nonsense, bluffing, and utter confusion since Grey R. was posting.... I was going to make some comments but I wouldn't dream of breaking up the shear entertainment! I may have to dig out my Three Stooges DVD just to get back to something slightly coherent. I can hardly wait for AWL to see this thread.
"There's battle lines being drawn
Nobody's right if everybody's wrong
Young people speaking their minds
Getting so much resistance from behind*
I think it's time we stop, hey, what's that sound
Everybody look what's going down"
*and capacitance from in front and behind...
Attachments
Well, set me straight, Fred. You know I enjoy cogent criticism; I'm just unclear about exactly what you're criticizing.
Woo-woo-woo! Spread out! Pick two!
Woo-woo-woo! Spread out! Pick two!
fdegrove said:
Not exactly very helpful. Care to elaborate so the less fortunate and the mentally challenged like myself can at least start to comprehend, 🙂
Hi,
Crystal clear to most of us.
I'm starting to feel sorry for you already...
Yank another chain please,🙁
Crystal clear to most of us.
I'm starting to feel sorry for you already...
Yank another chain please,🙁
fdegrove said:
What a waste of my time, 🙂
BTW, how did you think for the rest of the forum visitors?
Frank, Millwood: C'mon, guys, this isn't useful. Say what you mean (technically, that is) if I may borrow someone else's sig. It could be quite enlightening.
Hi,
A non-answer?
Don't think so.
How hard can it be to read a few datasheets on regs. and imagine real life situations as you read?
Milwood, if you stopped digging yourself into opposition, people might be more inclined to 'splain a little more.
So far you've been nothing more than a nasty wirewound corkscrew, how do you expect that is going to help you?
Cheers,😉
A non-answer?
Don't think so.
How hard can it be to read a few datasheets on regs. and imagine real life situations as you read?
Milwood, if you stopped digging yourself into opposition, people might be more inclined to 'splain a little more.
So far you've been nothing more than a nasty wirewound corkscrew, how do you expect that is going to help you?
Cheers,😉
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