Recently I started working on a custom LED Matrix displays and I’m very excited that LED Matrices for new displays finally arrived last night!

I knew they will be small, but actually seeing them in front of my eyes still shocked me a little on how small they are!   You can almost fit 4 of these in place of regular 8×8 matrix block!

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After a quick test, everything seems good, datasheets are accurate and pins are actually nicely organized. Left row red LEDs anodes, middle common cathodes, and right row are green LED anodes.

I ordered several varieties. Red LEDs are all the same, but when it comes to Green color there are some choices. There’s something that’s called Super Green and Pure Green. As name implies Pure Green is closer to wavelength of actual green color (512-525nm) while Super Green is closer to the yellow at 565-575nm.  Catch is that Pure Green LEDs are almost double the price of Super Greens. Another difference is that Pure Greens are significantly brighter and have much higher forward voltage than other LEDs. This creates two issues. One is that driver ICs might not be able to handle higher load. Another is financial as cost of the LED matrices puts affordability of the displays at risk.

Fortunately after visual inspection, I happy to see that Super Greens are actually look very green to me, and I plan to use them in the displays going forward.

I’ve finalized first version of PCB and already sent it to manufacturer. Hopefully I’ll get it back in couple of weeks, and they it will be really “fun” to solder all these resistors 🙂

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