SMD LED Matrix

3573544803_03000843fc

Everyone loves a good LED matrix hack, and we’ve seen our fair share, but never a 16 by 24 hand soldered SMD one. [bear24rw] and his team needed a project reflecting the interests of one of his classes, being an EE major, an LED matrix was just the ticket. Based on this instructable, he was able to cobble together a driver board; the code however was unacceptable, and he came up with a double buffer array solution. You can grab the eagle file and source code here, while you’re at it check out a quick video after the break.

[youtube=http://www.youtube.com/watch?v=VOljZt9pW5g&feature=player_embedded]

17 thoughts on “SMD LED Matrix

  1. PS. It also has a 100Hz refresh rate. I found that at less than 75Hz the flicker was noticeable.

    Kevin, if you are around, you need to get at least quadruple your 15Hz refresh rate so I’d concentrate on that first.

  2. use rgb smd leds arranged with the centres as anodes, and homemade plated through holes… :) requires double sided pcb but doable.

    interesting to note that with a little effort you can build this using ITO coated glass harvested from a dead touch screen, but arranging the LEDs in series on the vertical axis (i.e. RGBRGB) and shorting out all columns except the one to be lit.

  3. My company developed a display with 512 surface mount LEDs. I don’t remember the size, but they are smaller than normal SMT LEDs I’ve seen. They are basically like a grain of sand. Looks really nice, but the raw cost for the LEDs is $75 even when we buy direct from the manufacturer.
    I’m proud, actually, because although I didn’t design it, it was my idea to use discrete SMT LEDs instead of those LED array modules, which would have made it much thicker.
    Sadly, I have no links, because our website is lame and outdated!
    -Taylor

  4. Answer directed to jfmateos, I laid out the Led board in cadsoft eagle’s trial version, which doesn’t actually support boards of that size. To get the proper size, I printed one side that had the 2×20 pin header on it, and another that had my name and revision number on it. I then carefully cut the two laserjet papers to piece perfectly together, and ironed them both onto one piece of copper-clad. The result was an almost perfect etch, i had to go in with an exacto knife and cut a few of the smt led pads in half where they hadn’t etched completely, but I bet if I were given a full version of Eagle and the chance to do it again I could get a really sharp etch out of it.

    Glad you like it, the led board is actually single side. The cathodes (vertical columns) of all the leds are actually just pads for the leds to be soldered onto. I then soldered a piece of bare wire from an ata ribbon cable to each of the cathodes of the leds, and routed the bare wire over the anode traces through the air. It resulted in a perfect matrix setup, without the hassle of lining up 324 through hole jumpers.

    I was too young when I made it to have any care for making an instructable or document my progress, I was just caught up in what I was making/doing. I still get that way haha. This is the most documented that the led display board has ever been, hope you like it.

Leave a Reply to conundrumCancel reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.