@ToyKeeper, I always wondered, from a technical point of view, is it possible to simulate a constant output with FET driver by varying PWM intensity based on battery voltage? I know it’s not a constant ratio but if it is being measured and calibrated from factory with several data points, is it possible to at least maintain a somewhat stable output instead of letting the output drop like a slope.
So the firmware will have a 2d look up table based on mode and voltage and gives a PWM value for output, something like this:
VBatt L M H
4.0v 2% 9% 25%
3.9v 3% 11% 28%
3.8v 4% 12% 30%
3.7v 5% 14% 32%
3.6v 6% 16% 34%
3.5v 8% 18% 38%
3.4v 9% 20% 42%
3.3v 12% 22% 48%
It’s a very crude example that make a PWM based FET driver simulate a constant output driver. Would it be technically feasible, given the limited storage and memory of the controller chip and is there any interest form manufacturers or users to make it happen?
Or maybe the real constant current output hardware is cheap enough that this software solution doesn’t really make sense. However, given number of FET driven lights on the market (huge), this calibration at least makes it a bit more palatable for me to buy them.