Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

could anybody offer me a current limited circuit?

Status
Not open for further replies.
R

RF_beginner

Member level 4
Joined
Dec 12, 2003
Messages
75
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,286
Activity points
545
the current is limited between 400mA and 700mA,thanks!
 

Hi...

Ok, lets clarify ur Qs. If u mean a current source then u can use a current mirror using 2 transistors. If ur asking for a kind of protection circuit, there are many automatic so-called fuses available.
 

Check this circuit:

Here you have a PNP transistor, that has 0,7V between emiter and base.
D1 is a diode, that could be a LED diode, with 1,7V diode tension.

Then, the value of current in collector-emiter from circuit, will be:

Ice = (Vdiode - Vbe) / Rlimit

So, for 500mA => Rlimit = (1.7-0.7) / 0.5 A = 1/0.5 = 2ohm.

The current in Rload will be always 500mA, and regulated!!!

Chose a transistor that supports more than 1A in collector-emiter, for not burning.

Hope it helps.
Good luck
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top