Does it exist a 3.7V boost driver to 4.1V@1.4A that has at lower modes down to 3.1V voltage output

Flashlight Modding and DIY Parts
1

I am looking for a 1.4A boost driver which is able to run a 4.1V LED

when not running at full current the LED has lower voltage than a 4.2V Battery voltage

for this Nichia beauty

2

?
Buck-boost from zebralight?

3

yeah most likely a buck/boost driver, but not more than 1.5A for this UV non DTP pad LED, the additional 100mA I could bypass with a resistor

4

IMHO and experience , at this small voltage differences ( 3.7V to 4.1 V and down to 3.1V) , none of the existing buck-boost driver will do the job !!! But maybe , I'm obsolete ...

5

I am fine with a boost driver to 5V and then a linear regulator after it

6

The classic GDuP might work. It’s a Buck-Boost driver which supposedly works between 1.8 and 5V. It’s unique, but very expensive. It’s also really small, 14mm diameter!
It does up to 1.2A and three custom levels can be chosen when buying it.

The 1-Cell Buck Boost LED driver form German company pcb components should also work. It goes up to 1A, but only costs half as much! It only has one mode and has a diameter of 18mm.

7

A current resistor modded LD-29 with 2S input should work (LD-29 @ FastTech). Sense resistor is 25mΩ for 2.8A of current output, an R050+ in its place should fix it.

I don't really know what is the driver's maximum output voltage, but heard somewhere it goes up to at least 4V.

Fairly good 18350s available? Yes.

Good 26350s? Yes.

Nonsense. The driver raises voltage until 1.5A flows out to the load or it reaches maximum output voltage.

Cheers

8

Check DereeLight.

I’ve bought some of their 6P pills before for the driver alone, used in a very similar project, they used to run ~$18. The regulation is great as well.

ETA: Their selection is limited to one pill now, used to have 3-4 different models. The one available might work though?

From DereeLight