user46452: I would like to building a 8x64 RGB Matrix and connect it to my Arduino.
As this form factor does not really exist I would need to build one myself but now I am wondering if I should use addressable LEDs like WS2813 or APA107 and use FastLED or rather use 'dumb' LEDs and just multi-/charlieplex them using a MAX7221 or comparable chip.
What are some pros and cons I should consider with each one? I read that to many WS2813 can make problems but APA107 seem to fix that. But on the other hand most bigger matrices just use multiplexing........

user42539: The smart RGB LEDs will be brighter. Each device has its own control chip that controls the 256 PWM level for each of the 3 LEDs. So for an 8x64 array, you send in 3 bytes/device, 8x64x3 = 1535 btyes, pause a few microseconds, and the array updates itself.
Going the multiplexing route, you would do something like have 64x3 = 192 anode drivers (or up to 192, if not all are LEDs are lit up) to enable the LEDs across the display, and then 8 common cathode drivers to turn on each row one at a time for 1/30 to 1/24 of a second for minimal flicker. So 192 LEDs, 20mA each, the common cathode needs to be able to sink 3.84A
On the otherhand, 8x64 LEDs, each needing up to 60mA at full on, = 30.72A.

46452: <p>I would like to building a 8x64 RGB Matrix and connect it to my Arduino.
As this form factor does not really exist I would need to build one myself but now I am wondering if I should use addressable LEDs like WS2813 or APA107 and use FastLED or rather use 'dumb' LEDs and just multi-/charlieplex them using a MAX7221 or comparable chip.</p>

<p>What are some pros and cons I should consider with each one? I read that to many WS2813 can make problems but APA107 seem to fix that. But on the other hand most bigger matrices just use multiplexing........</p>
 42539: <p>The smart RGB LEDs will be brighter. Each device has its own control chip that controls the 256 PWM level for each of the 3 LEDs. So for an 8x64 array, you send in 3 bytes/device, 8x64x3 = 1535 btyes, pause a few microseconds, and the array updates itself.</p>

<p>Going the multiplexing route, you would do something like have 64x3 = 192 anode drivers (or up to 192, if not all are LEDs are lit up) to enable the LEDs across the display, and then 8 common cathode drivers to turn on each row one at a time for 1/30 to 1/24 of a second for minimal flicker. So 192 LEDs, 20mA each, the common cathode needs to be able to sink 3.84A</p>

<p>On the otherhand, 8x64 LEDs, each needing up to 60mA at full on, = 30.72A.</p>
