i am getting *so* much rework practice out of the current board design on the bench.

first batch reflow cycle was bad, baked the flux out before reaching temperature
tried to rework those, because shorts all over the place, but gave up after three days.

today, pasted and placed one more board. got too much paste on it, but Zoé helped me fix the worst solder bridges.
tested it, has some strange behaviour, rework some more and so on.
check schematic again, forgot a diode (thought it was just a tvs diode and left it out).

soldered on the diode, checked again, still bad.

checked diode orientation, of course it's the wrong way around... now it's on the right way, but the board is still cooling down. let's see if it's any better then :D

one more time. measured some more and now i'm pretty sure the 5V regulator does something weird. that pesky 2x2mm QFN package really hates too much paste...

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squeezed out a bunch of solder paste & cleaned it up. 9-pins in a 4mm² package is fun :D (especially with the large one in the middle)

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it works \o/ now i'd just like to know if i fried the MCU somewhere along the way. i'm still waiting for my debug adapter boards but i'll probably just make a cable tomorrow and get started with writing some code to enable the output and trace efficiency.

@ln everything looks so solderable when you're in CAD with 0.2mm traces :P

@steph hey, it basically just comes down to my bad pasting skills. de-soldering and placing it again is easy. even with that really cheap hot air and pre-heater.

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