I realize that driving an 8x8 RGB matrix seems to be a common thing. I've read through a number of threads, blog posts, and articles, and I still have quite a few questions / am kind of overwhelmed.
It seems that using some kinds of shift registers or LED drivers is a common way to drive an RGB matrix.
What I would like to do doesn't seem like a corner case. I would like to build an 8 x 8 RGB LED matrix. I am aiming for the matrix to be able to produce 24 bit colour per 'pixel' (8 bits per 'subpixel').
Some methods I've seen so far are:
- ShiftPWM [http://www.elcojacobs.com/shiftpwm/]
- Using several TLC5940 drivers [for example: octint, http://www.hangar.org/wikis/lab/doku.php?id=start:octint]
- Using several MY9221 drivers [http://www.seeedstudio.com/depot/rainbowduino-led-driver-platform-atmega-328-p-371.html / http://www.seeedstudio.com/wiki/Rainbowduino]
- Using several WS2803 drivers [http://arduino.cc/forum/index.php?action=printpage;topic=110537.0
I don't work electronics like that very often, and this is kind of a challenge for me. I am planning on making the matrix (connecting the RGB LEDs), so the LEDs could be either common anode, or cathode (right now I think they would be common anode).
Can some one please recommend an approach to driving a matrix like the one described above?
Also, the MY9221 apparently does something called 'Adaptive Pulse Density Modulation(APDM)'. I am not certain what that is (I am guessing it is similar to PDM). Does anyone know if there's an advantage to PDM over PWM?
Thanks for reading, and thank you in advance for any replies / input.