LED lighting fixture:new milestone

Time to share a little more of my progress constructing a LED light fixture.

Last weekend I completed an important milestone, I prototyped the circuit +power source that would drive the LEDs (turn them on of off) with dimming capability. The power source is a simple PC ATX power unit, a used one in fact.  The driver circuit is a simple MOSFET Transistor switch with a current limiting resistor, and a fuse to protect against over current in case a LED blows.

The dimming is done using an Arduino controller.  Never heard of Arduino?  They are a lot of fun, if you like to play with robotics or other types of programmable toys.  Check out: http://arduino.cc .  One day when my kid is a little bit older I hope to build small Arduino controlled robot car or boat with him.

Enough talking, here is a video of the prototype working:


It is dimming the LEDs up and down very fast just for testing.  Obviously the final Arduino program will dim very slowly to simulate sunrise then sunset.

Nice huh?  It is great to reach a milestone like this one when things work.  It wasn't all rosy all the time, though.  I spent almost an hour figuring out why the circuit wasn't working, and in the end I had forgot to make one connection.   Once fixed, it came to life!

I was only able to build this driver circuit thanks to the help of kcress from ReefCentral, as registered in this thread:
http://www.reefcentral.com/forums/showthread.php?t=1914090 . ReefCentral is a great place where you find lots of helpful people from all walks of life.  If you have a saltwater aquarium you MUST have an account there and participate in the forums.

Snorkeler