Sometimes I feel really dumb. I wish I knew half as much about electronics as you guys. I really need to learn more about PCBs and small componets. I work with larger electrical componets like ice cube relays, motor starters, timers and larger PCBs. When a small componet fails on a board, I just replace the board. I never get to work on the small stuff because it is not cost effective to have guys in the field trouble shoot boards. Cheaper to just replace or get it rebuilt on a bench.
Pavithra_uk: ... and waive the fun of controlling each LED individually? Nah, that is some essential part of "fun stuff" :)
Ramping is implemented now.
H: press and Hold the button (from any constant brightness level) ramps up,
SH: a short tap, then press and hold: ramps down.
Both work from off, then H ramps up from moon and SH ramps down from high.
Ramped levels are memorized in each group, so with a double tap (switch groups) you can switch between two arbitrary brightness levels.
DrJones, you must make a video of that, I want to see, i want to see 
Added the possibility to use only 1 or 2 leds; there’s a code to add a LED and a code to remove one.
In a mode with less than 3 LEDs, if you switch it off and on again, it uses different LED each time. If that reminds you of a certain fenix light, well yes, me too.
Ramp up, ramp down, add or subtract a LED, store that new mode - it got pretty flexible. Still not finished.
Do you have any plans to sell modified boards for them? If so put me down for one. :D
I could easily sell the programmed MCUs for the MCU swap; I could attach wires, too.
Sending modded drivers is more complicated: I need to get one first (does CNQG sell bare ones?), and shipping is also more expensive (bigger and more sensitive). We’ll see. First I’ll continue with the firmware until I think it’s finished.
Sirius9: maybe when I’m finished.
Dr.Jones if you can really can make all this and keep the whole thing reliable, I'ld be happy to pay postage back and forth to you to send you my driver to be modded 
I am more interested in buying ATiny loaded with custom Dr.Jones sw, I will unsolder that stock crappy mcu and solder good stuff in no time 
How did I miss this? Very excited for this.
I might just end up doing the master-slave setup with some 105C's :)
If you can spare a pin on the micro, program it to go high when the light is on and low when the light is off. It can be used to power the current sense op-amps and greatly reduce the parasitic battery drain. Best if you can put a little delay between when the pin goes high and the light is turned on.
I've done some tests with SRK of my friend. it draw 1.4mA when off. two Opamps draw 0.7mA & 3 Drivers (QX9920) draw 0.7mA when off.
so my plan is both OpAmp & Driver supply powered from Micro pin. + Battery monitoring resistor divider & temp protection also from it
ATtiny in power down sleep mode when off will draw 0.1uA. (WDT off. if WDT on it 5uA)
My friend need temperature protection for his SRK. Do you have an idea what should be maximum operating temperature ?
here my idea:
Thermistor (standard 10K) glued to behind emitter board. then check resistance. > drop brightness
problem is resistor divider need constant reference supply.
LM35 is a another idea.
The QX9920 is spec’d a 1 uA when off via the EN pin. You should not need to power strobe it. Not sure where your 0.7 mA is coming from.
If you use the internal 1.1V bandgap reference for the ADC, you don’t need an external reference supply.
I would use the LM35 type temp sensor (use the degrees F version, it has better resolution than the degrees C version). Power it via that power enable pin from the micro. Another possibility is to use a ATTINY85. It has a built-in temp sensor (but the uncalibrated accuracy is awful, like +/- 10C).
Once the light starts getting over 50C it becomes uncomfortable to hold. I would not want to see the temp get over around 65C, that is hard on the batteries (and your hands).
PM me your email address and I can send you the code that I use in my 5000 lumen Bridgelux light. It does battery monitoring, temp monitoring, fan control, etc. There might be something useful in there.
Yes I will use 1.1 internal reference. I mean reference for thermistor. LM35 is better idea.
PMed my email.
LM35 datasheet say minimum supply voltage 4V
according to graphs, below 4V reduce positive temp range (maximum measurement value).
Should be OK, but an STLM20 would be better. Works to 2.5V Many people make these type of sensors.
My driver uses a LM2936 regulator to drop 25V to 5V for the processor, etc. Total standby current for the board is < 20uA.
I’m using the ATtiny85 and it’s internal temperature sensor, I have yet to implement the readout routines though. I hope to get some hours of spare time for it this weekend… UI would be mainly done then, but I’ll add some more fun modes.
So could you theoretically swap out one of the xml with an xre/xpe and light it by itself or with the other two. Then ypu could somehow cut out the glass over the smaller emitter and stick an aspheric lens on it. Just light up the aspheric for throw, the two xml for flood, or all 3 for both. I guess the same current must go to all 3 leds though since it,s parallel? Maybe some kind of resistor just for that led?
I don’t know anything about how to do this, just dreaming. With so many multi-emitter lights I don’t know why they don’t stick an aspheric on one of them for a brighter “hotspot”.
Just amazing what you are able to do with these, DrJones! Count me in for a reprogrammed ATtiny when you have it all ironed out. 
Bravo, DrJones! You’ve managed to make the brightest bargain light cannon into the most feature laden one as well. Im looking forward to your next post.
I would like to add a charging/aux power jack to the side of my SRK. Can anyone tell me the best place to solder the positive lead?
