current limiting circuits ...?

Status
Not open for further replies.

bulerias

Junior Member level 1
Joined
May 9, 2002
Messages
18
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
129
hi,
where can i find current limit circuits (for 50ma current)example to build from scratch,
and is there any ICs that do that as a singke solution?
thanks for any help...
bull
 

Please check Classic Current Limit Circuit TR based.

Transistor is very cost effective and robust.
 

You can also use a programmable voltage regulator (e.g. LM117/317) + additional resistor.
Take a look at LM117/317's datasheet.

Mik
 

Try : JFET + resistor
 

This link shows you the current limiting with a N chanel JFET.

---> h**p://www.huebsch.at/train/Elektronik/Beleuchtung.htm

You must use a JFET with IDSS > 50mA
Check also power dissipation in the JFET

Here is my curves from Proteus (not the same JFET !) :
The resistor biases negativly the Gate.
You must adjust resistor to catch your current limiting value.
 

50ma Current Limit !!!

Hi,

A very nice current limit would be to use the TL431A chip
whis is widely available.

Look for it's datasheet on the www.

Bye.
 

Yes, TL431 is a good idea :

Bye
 

I think, using a transistor is a good sollution

In the image, the current is fixed by the formula: (Vdiode-0,7)/R
 

Status
Not open for further replies.
Cookies are required to use this site. You must accept them to continue using the site. Learn more…