UI suggestions:
Whilst I like ramping, I still prefer fixed modes because I can estimate run-time, and select a suitable brightness level, e.g. if I know it is going to have to last so many hours.
So make the ramp halt at fixed intervals, corresponding to modes. e.g. press and hold, torch ramps up to next level, then stops. Press and hold again, ramp up to next level. Brief press, then release and hold again, ramping reverses, this time stopping at each lower mode.
This is the Narsil, Anduril etc. ramping behaviour, except that they don’t halt at fixed intervals. Narsil does give a brief flicker as the threshold from 7135 only, to FET PWM s transitioned, but that’s not very helpful if you want a bit more power, but still to have confidence in your run time.
I’d like to see a quick and easy way to access batt-check. It’s a feature I use a lot, every time I pick up a torch that has it. It would be nice if the torch flickered a warning each time the voltage dropped to another level, corresponding to say 3/4, 1/2, 1/4 remaining (3 blinks, 2 blinks, 1 blink), then a continuous brief blink say once/minute below 1/8.
I’d like a “flashy” mode that turns the e-switch (or a forward clicky) into a momentary switch enabling me to e.g. signal morse, or an alpine distress signal, or just flash it around briefly and silently. Output level in this mode to be as memorised in normal operation.
Not sure how to get back out of this mode though. Perhaps only suitable for e-switch, where a battery disconnect could revert to normal operation.
And an energy efficient alpine distress mode that could last all night. 3 or 6 blinks, repeated every minute.
I like what you’ve done with the hardware. Fresh thinking.
Do you have a feel for what the thermal limitations will be, worst case, i.e. high cell voltage, low LED Vf, intermediate current setting ? Perhaps FAT-3 with direct drive FET will be more practical than SLIM-4. providing you have found a Pfet with a sufficiently good Rds-on.
I see the Consonance regulators automatically limit their junction temperature to a safe level by throttling back. Neat. Maybe good enough for overall thermal management of the torch if in close thermal contact with the shelf (e.g. silicone thermal rubber packing). Do they PWM nicely for the lowest levels ?
I’m guessing that you intend a spring bypass lead through the hole in the centre of the spring pad, then linked to the big + via on the other side.
Very interested to see how this develops.