This 30mm "direct-drive" FET+7135 driver build is specifically designed for the Convoy L6 with a 6V LED, such as an XHP50, XHP70, or MT-G2. Of course, it may also be adapted to any other 2S input/output 27.5mm momentary build.
The driver is flashed with firmware customized for this build with an ultra low resistance FET that gives you near-direct-drive performance (limited mostly by your battery, LED, and connections) with the ability to still use lower power levels, and utilize a temperature sensor, among other functions. A linear 7135 regulator has been added, but is only utilized to give a lower low, or moonlight, mode than the FET alone can provide.
The difference between this driver and the normal FET drivers is that it has been optimized for 2S+ cells and use of a momentary switch (power always connected to an external momentary switch; not a standard rear clicky switch). With the additional of an LDO voltage regulator, the quiescent current (drain while the driver is powered, but the LED is turned off) is greatly reduced when compared to a zener mod solution. This reduction is particularly important for momentary switch applications, where the power is always connected to the driver.
All drivers feature fast PWM and come with pre-soldered leads and stiff springs able to maintain firm contact with 2x26650 cells in the tube.
Because each driver is hand built and tested, This driver may take up to 10 business days to build, test, and ship.
D4 V2 (attiny85)
There are now two versions of the D4 V2 firmware for the Convoy L6:
Besides the turn on mode difference, the two versions are the same:
Convoy L6 Standard Electronic Switch Firmware
Standard Electronic Switch Firmware Low Voltage Protection. At around 6V under load, the light will step down the power level. At around 5.7V under the set point under load the light will shut off. You can override any low voltage shut down by holding down the electronic switch button. This system gives you ample warning and attempts to extend runtime before turning the light off.
This driver was made possible and is heavily inspired by many members of the BLF flashlight community, especially comfychair (initial concept and development), Mattaus (PCB layout and development), JonnyC (firmware), DrJones (firmware), and wight (singe-sided PCB development and advice). If you'd like to learn more about these drivers, and participate in further development, come visit our community at budgetlightforum.com