I have exactly the same driver as Werner posted (on image with cut trace). Strobe and SOS modes are annoying, but the most disappointed is PWM frequency in medium and low mode (it’s barely 130Hz).
Werner, what You can recommend to replace this PWM driver (correct me if I’m wrong - PWM driver is on the bottom with 10 legs? - in upper PCB we have buck-boost converter?)?
You said that could be done with nanjg (this mean ATTINY with software?), but what about other components??
Another disappointment - original driver hasn’t got battery protection
You can use a nanjg and strip down the 7135. Flash firmware with modes you like and connect the PWM out of the nanjg controller to the 3T6 driver and the power from 3t6driver to the nanjg like in the picture.
If you want battery monitor the standard resistors aren’t suitable and the wiring is also not correct because the voltage divider doesn’t sees the full voltage…
Check out the oshpark projects thread you might find a better base than a nanjg if you order some different resistors anyway…
I need to desolder this driver and check all traces. Maybe You have all schematic written down? I’ve got on eye Attiny13 with really good software. Maybe I could use it with TR-3T6 driver. Time will tell
All traces needed to get battery status detection and protection. If I understand the situation properly, point with +5V for PWM controller on Your photo is stabilized and don’t change value if I use 2 or 3 cells? (You mentioned about voltage divider). Or we misunderstand here?
Of course the voltage is lower that is important because the controller can’t handle the full voltage.
The full voltage can be get from driver easyly, ground is ground and the battery + can be easyly spotted and checked for continuity with a DMM.
On the nanjg you only need to cut the trace from + to the resistor R1 and connect the resistor with battery+ From 3t6. And of course you need to use different values of resistors and or another firmware depending on what you want to achieve.
I will send you comfys picture of a stripped nanjg to make this clear.
I just tested mine on 3x AA Ladda 2450. It could only run on low (~200 lm) and it ran for 51:30 secs
It drained from 1.44v to 1.34v
I fit the batteries by unscrewing the bulb assembly little by little.
I ordered 2 more legit TrustFire from Aliexpress with serial number. I tested until the light goes off with six AA and got the following.
High: 1:15:00 It dropped to medium brightness after a while.
Med: 2:10:00
Running six AA on medium is still ~800 lumen with good flood and throw. It’s a very good size as a self defense. It also has similar runtime to SX25A6.
I now have 3 TF-3T6 and I will use one as a six AA battery version. One will be a modded 3x 18650 2250 lumen. One will be 2x 18500 super shorty. The only reason I am going with 2x 18500 is I can only get 1x 18650 to work in low mode and it’s dimmer than normal.
