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LED Light Box help? Answered

 I am wanting to build a LED light box. This requires a LED filled pannel.

The pannel consists of  15 rows of 20 LEDs each. This is a total of 300 LEDs to be in a pannel 24 in by 12 in.

My concern is how to make this compatible with a normal 110 outlet and what kind of transformer I may need.  I have considered using a shop flourescent lighting transformer but I think that may be more than I will need based on voltage usage.  Thus I thought i would ask someone here if they know of a better way to create such a pannel.  The Pannel will have Red, White and Blue LED lights on it. So its necessary for the full effect of the 300 individual lights. 

Just want to make sure I do not over kill but also not make a fire hazard by under designing as well.


If you pulsed the LEDs, you will be able to get the same effect but using less power.

You could do this by generating a square wave and connecting it to a decade counter (or 3) to drive the 20 rows. Then use the output of the decade counters to switch on transistors to drive the LEDs. So long as the period of the oscillator is 0.1ms or less, you will be able to pass the Peak Forward Current into the LEDs instead of the DC Forward Voltage.

This will allow you to only draw 1.5A on a 9v supply, and so you will be able to use a simple off the shelf power supply.