actually this one. The v2 nanjgs use 380ma chips and have nicer mode spacing and come in 4, 6 & 8 chip versions. KD isn’t the only place that sells them though they were the first.
PWM
Pulse Width Modulation. A technique of varying the brightness of a LED by flashing it on and off very quickly, making it appear to the eye that the LED is dimmer. Good PWM is at such a high rate that you can’t notice it. But if you wave your hand in front of the light and get a strobe effect, the PWM is getting too low. Some use current regulation which makes the light dimmer without PWM and is also more efficient.
Here is a link that you might find useful that has some of the words and stuff related to flashlight stuff
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The problem with PWM is that it drives to led to HI then Off. On High, the led is less efficient than at a lower current level. Just because it is off for a small period of time does not mean the average brightness, as seen by user, is not lowered. I believe the bottom line in the CPF forum was that PWM is NOT the most efficient approach, because of this principle. I am wondering why this technology persists in drivers?
2.8A is already high enough for a small 18650 flashlight and just a bit higher will not have any visible difference.
The PWM frequency is high so there is no visible PWM.