For some context:
I bought a cheap zoomie that uses a round die led just to play with.
I took out the driver just to see how I can potentially increase the output.
I spotted two A1SHB P channel mosfets which are directly responsible for switching the led and decided to replace them with four A19T P channel mosfets (stacked an extra mosfet on each one).
The output did increase but this is where the problem started.
The flashlight never seemed to fully turn off and the led kept on glowing.
I have tried:
Using a smaller value pulldown resistor
Shorting out the pulldown resistor (the led still kept on glowing for some reason.)
Replacing the mosfets (with A19Ts because I did not have A1SHBs)
In the end I decided to get a replacement driver and an SFT25R to replace the stock led.
But now I want more lumens because the driver I have can only output 3A whilst the led can handle 8A so its really underdriven.
The new driver uses two A2SHB N channel mosfets which I now have ordered online and now I want to prevent screwing up the microcontroller this time.
I plan on stacking two mosfets on the existing ones and I don’t know of it will possibly create issues so I just wanna know.
You can install Convoy driver into it.
I’ve cut it and removed most components to fit S21E 6V3A boost driver just hanging in the empty space, soldered and bypassed a thicker spring, connected button, indicator LEDs but charging port positive pads tore off. Didn’t make any photos because it turned out very ugly, at least it works well
I don’t know enough about driver components to comment on what might be the cause of your malfunction if it is on the driver. With the exception that I’ve sometimes seen this happen with bad 7135 chips, but I don’t see any in your pictures of the driver.
I have also experienced the problem you described with e-switch lights never turning completely off with a bad reflow on the star. The cause is too much solder between the LED and the star. When the light is run at very high power, the solder might melt and cause a tiny bridge to form between one of the contacts and the central heat sink pad.
The larger the bridge, the brighter the permanent ultra-low is.
The solution is to reflow the LED off the star and use a solder sucker or copper solder wick to remove any excess solder before replacing the LED back onto the star.
