Not long ago i received my MT03 II (as in mark 2) “Devourer”, which can do around 9000 Lumen out of the box.
It’s a neat looking thing and obviously very bright…
Of course i was curious about the insides, and i also think it should be able to 12000 Lumen or more.
I already did the mandatory spring bypasses, but i need to do the driver too, and the heat management could use some attention too.
My questions mainly concern the driver.
Here’s a couple of pics with my comments:
This is what i found after disassembling the head.
Not enough cooling paste or maybe not enough pressure.
But that’s fairly easy to solve.
But what disappointed me is the thickness (or should i say thinness) of the shelf the MCPCB is on.
It’s only around 1.5mm thick, the MCPCB is also around 1.5 mm thick.
The MCPCB is held in place by 3 tiny screws in loose threads, so they can’t press the parts together properly
There’s also a big screw in the centre, sandwiching the MCPCB between shelf and reflector.
Not yet completely sure how, but i’m planning on adding a copper ring between MCPCB and reflector to incorporate the reflector in the thermal path.
Now the DRIVER.
Those coils are really tiny…
Very few through holes for the minus to the opposite side.
There are basically 3 step down circuits, one for each XHP70.
They use 2x R100 (0.1 Ohm) in parallel, resulting in around 3000 Lumen per LED.
So it’s a 0.05 Ohm shunt / sense resistance for each circuit.
Adding an extra R100 to it would make that 0.0333… Ohm shunt.
And that’s the plan, basically.
But maybe i should settle for 0.04 Ohm ?
But those mini coils kind of bugged me, so:
I desoldered them and sourced some fat ones from a class-D audio amplifier PCB i had laying around.
I’m not experienced with modifying this kind of drivers, so i have a couple of questions:
Am i on the right track with this, to have it perform better, or would it work just fine with those tiny coils?
Where do i find R100 resistors in that size, or should i use larger ones? (that will get less hot)?
Anything else i may have forgotten to think about?