AnsweredAssumed Answered

Small Scale Battery Charger and LED Driver

Question asked by rdcravens on Aug 29, 2011

I  am wanting to charge a small battery (allows for about 5 min of LED  time) and run an LED (small, bright, flashlight size LED) . 

I am looking to have this run from a dynamo (2 or 3 wire) that will  obviously have a variable voltage input from 2 to 20V - no need to worry  about the lower end (less than 5V) if needed. Obviously, two (or 3)  diodes will be needed on the input - lets not focus on that part.

Looking for inexpensive ($10 limit)

Looking for something that would properly charge the battery to allow for a long life (years?)

I was looking for the LM3622 - but since it is no longer produced I  did not want to track one down for the project as I may need quite a few more and also need to worry about failures down the road (it also needs additional components).

The picture is what I am trying to replace with something infinitely smaller (do not worry about the battery or LED)


Kind of an odd desire, but who knows - someone may know of something exactly like what I am looking for... I have not had any luck trying to fond anything even remotely close.


Any ideas are appreciated. Not one for the electronic side of the house - so I would consider myself a semi-noob when trying to tell me something. More on the mech side --- I know, I know... Pressure is pressure and it all works the same... :-)