I wonder if it is a bad FET, since there is no inductor on these drivers.
Just put together a set of the 20mm version of this exact same thing and so far, no problems with these little mini-monsters (XPL2-HD and XHP50.2-3V)
I’m no expert here but it might be worth a try. Changing between fast and phase correct pwm might solve the problem. I don’t know which one you have now.
//#define FAST 0x23 // fast PWM channel 1 only
//#define PHASE 0x21 // phase-correct PWM channel 1 only #define FAST 0xA3 // fast PWM both channels #define PHASE 0xA1 // phase-correct PWM both channels
Toykeeper would be the expert with this. Richard at Mtn might know how to solve the problem.
.
You might find a solution here. https://forum.allaboutcircuits.com/threads/mosfet-gate-ringing.151840/
Adding a resistor in series to the gate or lowering the frequency may help. But I have used this type fet+1 driver (blf x6) with a triple pulling similar currents without whine or ringing as they call it. I used NarsilM made for e-switch.
I want to say Yes to that, since looking at how the parts are laid out by the direct bypass of the positive line and the very short negative traces near the edge of the board, but I have no equipment to measure the XHP50.2 I have here and going by Vesture’s readings of the same LED, I could be pulling 13 amps.