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I was wondering if there was a single IC like the MAX6960 that could control a whole 8x8 RGB LED Matrix because the MAX6960 can only control a RGY.

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The Holtek HT1632 chip controls a 24*16 panel of LEDs - so it would control a 8*16 matrix of RGB leds. I'm not sure how easy they are to get hold of.

Also interesting RGB application of the TI TLC5490 here.

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  • \$\begingroup\$ HT1632 looks pretty handy...but couldn't find a place to buy them in a quick search. \$\endgroup\$ – davr Jul 20 '10 at 18:52
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I found no easy and affordable way to do this with a single IC, so I've "used" a project like this as an "excuse" to learn the use of FPGAs. I've managed to handle a single array of 20x16 led with 16 "gray" levels, driven from a PC via RS232 port with 50 Hz refresh rate with an Altera CycloneII EP2C5 and a transistor for each row and column. I don't think it costs much more than a dedicated IC.

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    \$\begingroup\$ I am not sure how much you paid for your FPGA, but it is more. A dedicated IC plus a micro-controller will not break 20 dollars in single quantities. I do think that using the FPGA is a cool solution and +1 for learning one of the biggest emerging technologies around. I think FPGA development should be something well taught in Uni. Many embedded developers are switching to them because they are so flexible. \$\endgroup\$ – Kortuk Nov 23 '09 at 16:34
  • \$\begingroup\$ I used a Pluto 3 board I already had at home (knjn.com/ShopBoards_RS232.html). The matrix driver used less than 10% of FPGA resources but a lot of I/O pins. With external demux to drive columns, the smallest board should be enough. Yes, I'm aware this is more expensive than the custom IC+ micro solution, but I think it's worth it: I learnt to use Quartus, and the satisfaction to "draw" a schematic on screen, and see the FPGA that "execute" that schematic in the real world is priceless :-) \$\endgroup\$ – Axeman Nov 24 '09 at 9:45
  • \$\begingroup\$ Excellent reason to master FGPA :) \$\endgroup\$ – jancha May 7 at 4:54
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Yes, well sort of The Maxim MAX7219 or MAX7221 IC's can be cascaded to give you control of up to 8 8x8 LED matrix via SPI

Not perfect, but code examples are available... That should make it least the programming a bit easier.

http://www.arduino.cc/playground/LEDMatrix/Max7219

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  • \$\begingroup\$ Each can control an 8x8 matrix of single color, 64 LEDs, so you'd need 3 of them to control an RGB matrix. I didn't look into it to make sure it can actually handle a 24x8 matrix (what an RGB matrix really is), or if it would only handle 3 separate 8x8 matrixes. \$\endgroup\$ – davr Jul 20 '10 at 19:02
  • \$\begingroup\$ You couldn't do an RGB matrix like this. Three independent MAX72xx chips can do three independent 8x8 monochrome matricies because they each have independent anode and cathode lines. But an RGB matrix typically has common anode (or cathode) for all three colours combined; as such you couldn't use three separate MAX72xx chips to do that. \$\endgroup\$ – LeoNerd Jan 7 '16 at 22:46
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Driving large LED arrays is one of the "killer" applications for XMOS devices

Leon

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  • \$\begingroup\$ It can control a 32x16 array of RGB leds, but it's not cheap ($150 for the board alone, $350 for the board + LEDs + misc cables) \$\endgroup\$ – davr Jul 20 '10 at 18:59
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You can use 8 of the TLC5947.

http://focus.ti.com/lit/ds/symlink/tlc5947.pdf

TLC5947 is 24 channels of PWM controlled by shifting in 12 bits of brightness data for each channel. This would give you would give you a nearly continuous spectrum of color for each LED (3 channels per LED -> 8 LEDs per 24-channel IC).

The 8 of them could be controlled in series (look at the example on page 1 of the datasheet), so you can essentially treat them as if they are a single IC with 192 registers each of 12 bits. Though note that this will divide your refresh rate by 8, given any particular clock speed.

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