LM 317 0v

[Scarionn]

How can I go down 0v with a LM317? 

[Bored@Work]

By following the procedure in the datasheet, or by using a better device.

[Scarionn]

I can't have a negative rail in my project, and de LT3080 is rare in my cuntry. Do you no where can I buy the LT3080?

[Zero999]

The LT3080 also requires a negative power supply to work down to 0V. It has a 0.5mA minimum load current, which needs a negative power supply, at 0V.

Fortunately, there are ways to get a negative supply from a positive supply. How are you powering the circuit? Are you using mains or a battery?

[Scarionn]

I'm powering my cirquit whit the mains. I'm powering my cirquit with 24v (12+12).

[nick.sek]

This is one way to approach it, but I got to agree with the boys here; offsetting it with a negative voltage is the best approach; as it will offer more stability:



But if you have two 12 volts sources you are in luck, because you can make a relevant negative voltage to offset the LM317:

[amspire]

I'm powering my cirquit whit the mains. I'm powering my cirquit with 24v (12+12).

If there is a transformer, there are always ways to get an extra low current negative supply such as this:



Richard.

[Psi]

If you only need low current you can always put a voltage divider on the output of the LM317.
Can't get to zero but you can get it down quite far.
Obviously you then need a higher input voltage to get the same output.

[Zero999]

The following thread gives some examples:
https://www.eevblog.com/forum/beginners/zero-volts-from-a-lm-317/