@hp @Doomstrike re that IC being 40-50C, I'm not a magic smoke doctor but that seems like a tolerable amount of heat, if it settles at that level. It's toasty, but I don't _think_ so much that it'd be awful junction temperature on the inside. Plastic enclosure might get a bit warm as it dissipates that to atmosphere, but not hot enough to be a safety concern, and 🤷 cheaper to not bother with fancier cooling if the chip's not in danger, is the usual mass production ethos.

@hp @Doomstrike It could also cool down more once it boots successfully. If there's not enough supply rail capacitance, one possible failure mode is the microcontroller initializes, tries to power up some hungrier parts of itself or the board, that extra current draw causes the supply rail voltage to droop, triggers brownout protection, microcontroller resets, rinse, repeat. Effectively running at 100% utilization in a boot loop, instead of initializing then being mostly in low power sleep.