On Oct 16, 1:02 pm, Phil Gardner wrote:
On Mon, 15 Oct 2007 21:55:23 +0000 (UTC), "Jim Backus"





wrote:
On Mon, 15 Oct 2007 15:02:15 UTC, Phil Gardner wrote:

HI
Just bought 4X 2700mHa Ni-MH AA battery's my old charger is not up to
charging these in a reasonable time C/10 so im looking to build my own
charger.

I have a 1.5 amp power supply what I need is a variable current
circuit add-on- about 150-800 mA but cant find anything Simple! as in
DIY simple.

Any thoughts, suggestions?

LM317 voltage regulator IC set up for constant current.

Googling on "LM317 constant current" produced this:

http://users.pandora.be/davshomepage/current-source.htm

remember to mount the regulator on a heatsink - a square of 1/8 inch
aluminium a couple of inches square should do the job

Thanks but the problem with the 317T and also the L200 is R=1.25/I
Fine for a fixed current but hard to achieve a variable one.- Hide quoted text -

Due to the low value R not available as a variable one? How many
different currents do you want? Just switch in different resistors.

Alternatively use a simple transistor as a current source.

MBQ