Hi all
Just wondering if anyone has had success upgrading the driver from a Trustfire TR-S700, or if anyone can point me in the right direction?
It is controlled by a magnetic switch so I haven’t found a suitable replacement driver at this stage. It runs 7 XM-L2 leds in parallel, from what I can tell at about 1.4amps per led.
Thanks 
Hi!
First I would do - use bigger wires to LED, bypass all contact springs, use high drain cells.
It looks like (I suggest cells are in parallel) the driver works as current limiter (in terms of controll of current), sense voltage is taken from R4-R7 resistors, IC labeled K203 seem to be opamps (which work more like comparators) (I have no idea why there are three of them) which shut down transistors when voltage drop over R4-R7 exceeds reference voltage set by precise voltage divider (two small resistors beside K203).
From what I see the driver seem to be adjusted to very high current ( so wires, springs and cells might be a bottleneck).
Total resistance is sum of Rbattery(internal resistance)+Rwires+Rinductance(wire of it)+Rdson(transistors)+Rsense.
So I think if change of wires would not help you might add some resistors in parallel with R4-R7, or even change transistors (not all N-ch FETs are ok for that).
However all this are just guessing as I dont see all the connections on PCB and have not tested drivers of this type.
I hope our experts here would share their knowledge. I’m interested in finding out, too.
Thanks for the advice pro22000. This torch is really heavy and should be able to handle a lot of heat. If it was running off something similar to the BLF SRK driver @ 20 amps it would be fantastic.