50x50 common anode and common cathode led matrix Display

Guys , can someone help me out ? my project is gonna to do 2500 led diode which 50x50 led matrix display.
But, I don't know how to make an installation and what materials should I have. Now, I tried to use Tlc5940 but seems it cannot control so many led.

Can someone tell me what should I do ?

The MAX7219 can drive a 8x8 matrix; you can get ready-made panels with that chip built in that are designed to link together forming a much greater panel. This is the easiest way to build up such a panel.

Or if you want RGB colours and so, get a few strips of WS2812B addressable LEDs. Refresh rates of such a big number will be no more than about 10 fps, though.

Do you want an ON or OFF matrix or

To drive a 50x50 matrix you will need 100 output pins. You could reduce your matrix to 48x48 and use six 8-bit shift registers per side or expand to 56x56 and use seven 8-bit shift register per side. One side will only have one output on at a time but that output will have to handle the current from 50 LEDs. Typically you would choose to put the high current sinks on the Cathodes where a simple NPN transistor or N-Channel MOSFET would do the trick. You'll need a current limiting resistor on each of the Anode output pins and a resistor between each Cathode output pin and the Dase/Gate of the transistor/MOSFET.

As already mentioned, the achievable frame rate limits multiplexed displays. Find out yourself by building a small matrix and drive it by the 50x50 code.

I'd favor the use of light strips with integrated controllers (WS2812B...), with no risk of flicker.

The ultimate LED matrix would be made of boards with one Tlc5940 and 16 LEDs along the edge. You would use four side-by-side for a 64 element row and stack them 50 high to get a 50x64 display.

They can handle data flow at 30 MHz so you might want to use one of the faster ARM processors to drive it.

What's your plan to power this? Lighting 2500 LEDs, even at a modest 10mA each, represents a load of 25-amps.

johnwasser:
To drive a 50x50 matrix you will need 100 output pins.

That would give you a duty cycle of no more than 2%... so the only way to get decent brightness is increase the current in the LEDs. Gonna be a serious challenge to power and control a display like that!

Hi,
Welcome to the forum.

Please read the first post in any forum entitled how to use this forum.
http://forum.arduino.cc/index.php/topic,148850.0.html .

What is the application?
Display images or just digits?
How physically big is your 50 x 50 matrix?

Thanks… Tom… :slight_smile: