Hello
I found solutions for my power supply projects for voltage
Now I still have the current and I'm done. I want a constant current source design. I went to youtube and I found some LM317 uneffeicent designs. This will be horrible with me because I'm working with current controlling on voltage like 36v and less. The LM317 will make thermal shutdown anyway. So I want an idea please

 

What value current do you want?
What voltage will this current produce across its load?
Is the input voltage to the constant current generator 36V?

 

I want to control current to not fry my breadboard in case I make a mistake I recommand 5 amps and less will be good

 

Yes the input is 36 volts

 

The LM317 has built in current limiting. It reduces the output to 1.2 V. The LM317 is inherently limited to ~1.5 Amps.

Current limit and constant current are different. There are different current limiting techniques too. One is foldback current limiting.

 

Try a Lm338 it will go to 5amps, or an op amp constant current regulation.

 

I want to control current to not fry my breadboard in case I make a mistake I recommand 5 amps and less will be good

So you just want to protect the voltage output of your power supply with a current limit?
Do you want a constant current or a fuse type circuit that shuts off the voltage until the short is removed?
The advantage of the electronic fuse is that it requires no heatsink, even for high current protection values, such as the 5A you stated.
5A *36V would be 180W of dissipation for a short circuit.

 

Sorry I can't use LM338 or LM096 didn't find them anywhere
Now anyway, I want to regulate the current output and control it of my power suppy.

 

But if there is no way to make that circuit I need you please to tell me how to make a limit of 5 amps

 

These are easy and cheap.
http://www.ebay.co.uk/sch/i.html?_o...0&_nkw=5a+thermal+resettable+breaker&_sacat=0

 

This is a circuit breaker
Well I see there is no way since no one answered. Well I'll do my best in the power supply, voltage regulation with no current regulation.This is what I can do. And after a while I'll buy that 30v 5A power supply.
Thank for your help !

 

Well I see there is no way since no one answered.

I answered and asked you a question in post #7.
You didn't reply.

 

No bro, I want to control the output
For example I want to charge a 1Ah li-ion battery. I will set the current to 1Amp to not demage it or to not wait long time to charge it

 

No bro, I want to control the output
For example I want to charge a 1Ah li-ion battery. I will set the current to 1Amp to not demage it or to not wait long time to charge it

You do know that, if improperly charged, lithium batteries like to catch fire or explode don't you. Even the experts get this wrong - e.g. Samsung and http://www.skybrary.aero/index.php/Lithium-Ion_Aircraft_Batteries_as_a_Smoke/Fire_Risk
You should use a proper lithium battery charging circuit.

 

Yup, bro, you don't want to charge a Li-ion battery with a constant current, unless you are looking for some pyrotechnics.

 

Are you asking about adding an adjustable current limiter to the output of a power supply? If so, the there are only two approaches - switching and linear. Linear will dissipate a *lot* of heat but is simple to design and build. Switching runs much cooler but is much more complicated.

ak

 

And how does switching work ?

 

https://en.wikipedia.org/wiki/Voltage_regulator#Switching_regulators

https://en.wikipedia.org/wiki/Buck_converter

ak