NewLinuxFan

I had something similar happen to me. My board designed for Teensy 3.5 worked fine. Then switched to Teensy 4.1 and surprisingly the linear regulator got quite hot without a heatsink. DC-DC converter fixed that.

Thank you very much! That goes a long way to answering what went wrong on my current design.

Please show us the answer... 😄 You can hook up an oscilloscope in trigger mode and make a video of your laptop burning...😄

I wonder what the transient would look like... :) (It'll either overshoot or undershoot... my money's on the overshoot.)

Seems way easier to just cut open a USB cable and add a through-hole diode to the red wire with the line end pointing towards the Teensy. This cable could be used for multiple Teensies. And as mentioned previously, a diode for Vin would protect...