Sense resistor size seems to be 2010 imperial. For an Osram Ostar Projection Compact KW CSLNM1.TG, you could swap the R010 with two R025 sense resistors in parallel. This would set the driver at 4.8A theoretical, probably driving the emitter at slightly less effective current (4.5+A), which is a nice figure in practice.
hi barkuti, simon says that his 17mm 1.5A isn´t suitable for red led. Due to the red led 2.4V vs the white led 3.0V. With a red led, that driver would transform the voltage difference into heat? Is it reliable for long periods of use on a C8+?
Mmmph, that sounds strange to me. The driver clearly is a buck driver:
It has an inductor and a sense resistor onboard. Besides, valid input voltage is listed as 3 - 8.4 V.
In my experience, a buck driver can usually work fine outputting lower voltages. I once modified a buck driver from Sofirn to output a lower current and drive a red XP-E2 led with it. And it worked. But of course, I haven't tested the above single mode driver.
@Barkuti
The sense resistor seems to be the main reference for output current control. This 22mm driver has a resistor R010 and is limited to 6A, but 17mm has the same resistor and is limited to 5A. Is there anything else to regulate the output current?
By Ohm's Law V = I × R, if you calculate it for both driver types you'll get 60mV sense voltage for the bigger diameter ones (∅22 and ∅20mm) and 50mV for the ∅17mm one.
The sense voltage must be set somewhere in the firmware I bet. The actual intricacies of that I don't know.
Being a linear driver, it will deliver up to 6A. To deliver 6A there must be a minimum voltage difference between input -cell voltage- and output -emitter- because current flow times resistance (the very battery cell, springs, switch, cables and contacts, etc.) causes a voltage drop. So, once battery voltage drops below a certain point, i.e. once it gets close enough to the Vf of the emitter, the driving current will start to drop below 6A, reducing progressively down from there as it happens with “MOSFET direct drive” drivers.
At present, Chinese buyers mainly feedback two opinions. One is that the reaction speed is not as fast as Anduril, and the other is that the ramping time is a bit long.
This driver is similar in function to anduril, but the code is rewritten, which is more conducive to compatibility with components.
The charging version of M3 will be launched soon, it applies this ramping program.