I need to drive and dim 4 parallel LED strings.
Each color (see below) dims separately. Another constraint is minimising the number of wires running from the light to the driver.
Here are my options as I see them.
Option A is the baseline, each string is driven separately. It's not physically reasonable in my case as the LEDs and the driver are on different PCBs and that would create a lot of wires.
Option B is how I do it currently. Each color is connected to a separate CC driver (LDD-300H). Although it works fine now and the brigthness seems pretty even, I know there are concerns around current imbalance between strings. I could probably connect the positive ends also?
Option C is to use a multi-channel CC LED driver like LP8860. Presumably I could connect the positive ends, which would leave me with 5 (1 positive, 4 negative) wires going from the light to the driver.
The space on the light PCB is pretty limited, so putting anything other than resistors on it would be difficult.
Am I missing any options? Am I wrong in my assumptions?