LED Matrix power

Hi,

I want to control a white LED Matrix 12*8 by arduino. what are the possibilities to power this matrix? I’m going to design an ac/dc power supply (Transformer, rectifier and an IC voltage regulator) for powering the arduino (9V or 12V)

The first thing is to calculate the current required of the supply. How many LEDs can be powered at once? What is the current for an individual LED? What else needs power aside from the Arduino? Add 80 to 100mA (very conservative) for the Arduino itself. And please consider a switching mode power supply. They are much more efficient and smaller in size.

I want to power the matrix at once. Each LED drops 3.4V and a current of 20 mA is passing through each column formed of 8 white LEDs so for the total matrix there's a 440 mA current intensity plus the 80 to 100 mA.

MrElec:
I want to power the matrix at once. Each LED drops 3.4V and a current of 20 mA is passing through each column formed of 8 white LEDs so for the total matrix there's a 440 mA current intensity plus the 80 to 100 mA.

Why do you feel you need to build your own power supply instead of buying one?

In fact i've to buy the adequate transformer, this is a final year project. My advisor demanded to design all the chain to control lighting the LED matrix by arduino.

If each of the 8 LEDs in series have a forward voltage drop of 3.4V your power supply will have to supply at lest 27.2 Volts. Twelve strings of 20 mA each will need a 240 mA supply. You will probably want to have current regulation. When you run the strings in parallel the current won't necessarily split evenly. It's probably safe enough if the maximum continuous current capability of the LED is much higher than 20 mA (say, 30 mA).