Overzealous with hot air gun


As i was revisiting my arduino power supply , i changed the shunt resistor on one INA219 board and after that it stopped measuring voltage and current. Not wrong values, zero. I checked the code, looked alright.

Time to pull the el-cheapo usb microscope and do some close up on the board
Aha !

Good ina :
Bad ina :

Seems i did not protect the chip from heat enough while soldering the shunt resistor.
Oh well, time to learn how to do tiny soldering.


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