adding current limiting to a power supply

[palstanturhin]

Current limit
http://www.ti.com/lit/ds/symlink/lm138.pdf
page 16...

[KatieandDad]

Page 14 confirms what I originally posted.

[Elvee]

Originally Posted by MarianB

@Elvee you seem to enjoy contradicting me just for the fun of it...

Initial load regulation is 0.1%. If you add 0.33 ohm in the output, this will be degraded to more than 10% for a 5V output. I don't think a degradation by a factor 100 is negligible.

ANY active current limiting would imply a shunt resistor and so a voltage drop on it, but it is small enough so you are not worryed, and for the life of me i cannot understand what is souch a BIG issue few tens of volts drop? the author did not mention the exact purpose of the supply, but as i sayd mV preccision and preccision current limmiting is not likely to happen with thys tipe of regulator.

ANY decent regulator includes this resistor in the feedback loop, making it completely transparent. That is the case with the LM338 for example.

Originally Posted by KatieandDad

MarianB there are Trolls on all the forums. Just ignore them.

Are you talking about me?

Originally Posted by KatieandDad

Page 14 confirms what I originally posted.

That is sheer madness: adding a second excessive regulator because the first one is already oversized.

Using the right part in the first place is much more effective and simpler than all these half-baked solutions

[MarianB]

It's sad to see the lenght some people would go just to get the last word, just to be the ones that are right... it is verry dissapointing to see that in stead of trying to really help the ones in need, some people prefere to just dissagree with other, just for the fun of it, hell yeah, we are waaaay better than the others why should we bother beying civilised? our role should alway be to cast aside anyone stranger to our grup no matter what the reason, even if that means looking for a needle in a hay stack, sooner or later we will find a hole on he's boath and so a good enough reason to just hunt him down no matter what...

Sad, and dissapointing... i had wanted to show something way better than anything you can do with this tipe of regs, much more precise, but as i see some people can never be satisfied cus they do not want to... why bother? it is obvious something wrong will be found in anything i say so the hell with it...

All the best wishez too all of you, even to you @Elvee, honest

[sofaspud]

Anyone opposed to just installing a panel ammeter?
Engineering is often a study in compromise (OK, maybe not so much with engineers) and the OP has been given a plethora of options. I suppose he can pick his poison.

[Elvee]

Originally Posted by MarianB

It's sad to see the lenght some people would go just to get the last word, just to be the ones that are right... it is verry dissapointing ..
....
...much more precise, but as i see some people can never be satisfied cus they do not want to... why bother? it is obvious something wrong will be found in anything i say so the hell with it...

All the best wishez too all of you, even to you @Elvee, honest

I judge technical propositions purely on their technical merits.
I think that's all the OP is interested in.

If you want to make it a personnality issue, that's your responsability only.

[dodo]

if someone dont care read the data

[MarianB]

@Elvee, You really do need to get the last word no matter what, don't you? Ok then, anything you say after this goes, i promise i will restrain myself no matter what you say, it's all exactly just as you say

Cheers.
Marian.

[dietnews]

Originally Posted by sofaspud

Anyone opposed to just installing a panel ammeter?
Engineering is often a study in compromise (OK, maybe not so much with engineers) and the OP has been given a plethora of options. I suppose he can pick his poison.

thanks sofaspud and everyone else. at this moment i'm not sure exactly which route i will take but between everyone's posts i've got quite a number of possible solutions.

[MarianB]

@dietnews there are litteraly loads and loads of ways to go, linear or switching, you first have to make sure what you need the most, what you want the unit to be used for, do you need preccision voltage regulation, preccision current limmiting, low ripple and/or noise line... make up your mind exactly what you want and what compromise you would be able to make, then it will be werry easy to choose the way to go.