Update on the RGB+UV buttons project.

I'm doing a bit of research on how to implement the LED drivers, This is what I have so far.

possible solutions for driving the LEDs required.

1. a TI TLC5940 or TLC5941(this 12 bit PWM allows the most control over each LED, but uses an SPI interface)
2. a Philips PCA9532 (only 8 bit PWM and it has an i2c interface.)
3. a Maxim MAX6964 (only 8 bit PWM and worse the top 4 bits are global to all LEDs, but also has an i2c interface.)
4. use an ATMEL uC (this requires coding and debugging and is limited to 10 bit PWM on most chips.)
5. a Philips PCA9533; 4-bit I²C LED dimmer (this is only a 4 channel driver)

solution 1 requires a chip to convert i2c to SPI.
solutions 1,2,3 require two chips to control 32 LEDs, omitting the UV LEDs would allow a single chip solution and the knob to be controlled as a single location.

solution 4 may be done with one chip, but a two chip solution solves the ISP problem.
solution 5 would control all locations at once, also like colors need to be wired in series.)