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.
Hank, if you are replying to my question about the V2 Nanjg driver, I wouldn’t want the 3A version. I’d want the XP-G2 with the 1.52A or 2.2A V2 driver. The V2 is nicer, not just because of the slightly higher output, but mostly for the better modes offered since it has the moon mode available as the low.
I ordered and received the bare host. It looks exactly like on the pics, the reflector is very very light OP and about 11.7mm high, pill is screw in with a retaining ring for the driver. Looks good. Specs on the site are correct.