SOB1000 v. GD1000 at lower voltage

[Blindasabat]

I have an SOB1000 driving a Cree Q3 light and it seems much brighter on 2xRCR's (8.4V+) versus on single RCR (3.7V+). Will a GD1000 run the full 1A on a single RCR while the SOB1000 is not?

 

[Justin Case]

The SOB has a fairly high voltage overhead to run in regulation in my experience with a small sample. Vbatt of 3.7V isn't going to be enough to reach full regulation. You probably need about 4.5V or so. That's why 2xLi-ion looks brighter. The GD1000 should deliver 1A drive current to your Cree using 1xLi-ion. The GD also should maintain high efficiency even when Vbatt is close to Vf, which could be the case for your setup.

 

[Blindasabat]

Thanks Justin Case. I may have to try a GD driver in my planned KX1 mod.