Modular Panels

 

 

I have just prototyped a modular 8x8 LED matrix board. To show you how simple the wiring is I have made it on a single sided PCB.

These panels can be joined together to form a larger display, chained together or be used individually.

The video is of a scrolling background test. The background is set up as a wraparound cylinder with the LED display showing a selected portion.

 

web partially weeded 8x8.jpg

The photo shows a mostly weeded board. The red circles highlight the dregs yet to be removed by weeding.

The photo also highlights how critical it is to get the board setup as level as possible.

Single sided PCB substrates tend to warp and have high and low spots and you can end up with under and over engraving.

The yellow oval highlights some under engraving. Both situations are not desirable. Over engraving makes tracks too thin and under engraving can leave short circuits.

 

web 8x8 PCB back side.jpg

The back side contains the connectors and some wire links. It is only partially populated at present but the board provides full functionality.

The unpopulated links are to reduce inductance thus will reduce EMI and voltage sags.

 

 

web 8x8 partially assembled but fully working.jpg

A three wire interconnect including voltage lines. It makes it so much easier!

All LEDs have been installed for a fully operational panel but only some decoupling capacitors installed but that shouldn't hinder initial testing.

 

The LEDS and PCB perimeter have been set to allow modules to be butted together and retain even LED spacing (unlike the preassembled 16x16 modules).

It highlights a Catch-22 with the LED spacing - the tighter the LED spacing, the narrower the PCB perimeter needs to be to the extent where it becomes impractical.