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A Google of LM317 Current Regulator will bring up applications where the old LM317 adjustable voltage regulator is used a s a current regulator to limit current. Additionally the data sheet for the LM317 shows current limiter applications. That should serve as a start.
Ron
Current does not simply blast out of a voltage regulator at full strength. Only a dead short draws as much current as is available.
The load draws only as much current as it needs. So you probably do not need a current regulator.
Your 7809 and 7805 voltage regulator ICs have good regulation up to 1A but limit the max current to about 2.2A. They limit the dead short current to about 750mA for the 5V regulator and to about 425mA for the 9V regulator.
Sor simple PSU apps like this I use two regulators in series, the first LM317 needs just 1 resistor to work as a current limiter, and the second (voltage) regulator can be a simple 7805.
You will need about 5 volts overhead for the LM317 plus 3 volts overhead for the 7805, so to get 5v out you need > 13v input at all times.
A load draws only as much current as it needs.
I am having trouble absorbing this :-/
Can you give me a basic explanation perhaps? If I had an LED attached to a voltage regulator (lets say this one... **broken link removed**), what current would it draw???
If you buy a bottle of whisky do you drink it all and fall down, hopefully not, you drink at much or as little as you want.
It would destroy itself - you MUST feed an LED from a current source, a simple resistor is all that's needed - then apply ohms law.
Don't buy No-Name-Brand LEDs that do not have a detailed datasheet.
They don't reveal the angle of the beam for those cheap LEDs. It is probably focussed into a very narrow beam to make the brightness number high but then it makes only a bright dot of light which is useless. Its quality is probably poor so it might not last very long.
Dear Beakie, I just found "Ohm's Law for Beginners". Go to the top of this page and click on "theory". The third item on the page breaks this current thing down to very simple terms...if that's what you need.
I understand ohms law... I just wondered about voltage regulators. Thanks though...
If you understood Ohms Law, you would not have even started this thread. A bit harsh perhaps, but true.