Hi, I am using an Arduino R3 Uno & PCA9685 via I2C to drive a dozen single coloured LEDs on a mimic panel - works well. Ideally, I'd also like to have bicoloured leds (red/green) that show on the mimic panel whether an motor is on or off. Of course, I could just use two leds, one red, one green, but can I do this with just one? I have some 3 wire leds (common anode) but can't get my head around how I could do this. Has anyone already done this successfully? Thank you. Paul
It appears the PCA9685 can only sink current. You would need a driver pin for each color connected to the individual cathodes. You could only drive 8 Leds because each one would require driver 2 pins. You may need to put the current limiting resistors on the cathodes if the current is different for the red and green to get the same light level.
Hi. Thanks for your reply, I had a feeling that might be a problem. Worth the question though. Thank you. Paul