Fried two lopy4 and pytrack
I have an application that will be powered on at all times, I've selected Lopy4+Expansion Board 3.0 from one side, and Lopy4 + PyTrack on the other, basically the pytrack transmits GPS position to the other lopy. Both modules have an IP67 case from pycom.
I've setup two buck regulators in order to output 5v and tied with wires directly to Vin and GND (these wires are soldered to the module pin header) and module was plugged on pytrack.
As soon as I applied power to the buck converter realized that the lopy led light didn't do any heartbeat and removed power inmediatelly. Now I have 2 fried lopys and a pytrack that doesn't get even recognized through usb.
Still need to find which component broke (I have already buyed the regulators) but with pytrack don't know which component is broken.
I know that I cannot apply power to 3v3 pin (as is an output) but why this happened when appying to Vin pin? Anyone had this experience? I have two new boards but I will wait till confirmation from anyone that had a similar experience..
@River Vin on the module pin header is the input for the module, but the output of the Expansion board or Pytrack...
My guess is that the modules are possibly OK (what happens if you power them this way, without inserting them into the expansion board or Pytrack?), and it's probably just the expansion board/Pytrack which have an issue, is that not the case?
Not sure what the best option is to power the Expansion Board or Pytrack this way. Usually it's done via either the USB port or with a battery. You could probably use the battery connector (just make sure you do not connect USB at the same time, otherwise the board may try to "charge" the power supply...). An alternative cold be to use a USB connector. Not sure if there is any other access to the board's power input.
Of course, before connecting I've double-checked that the output of the buck converter was 5.0 volts.
did you check the voltage our of the regulator first?