Dear all,

Is it a good idea to sandwich a tiny DC motor (3.0V, 20.000 RPM, 5x19mm, 30mA typical running current in the given application) between two interconnected PCBs? If yes at all, what precautions should I take, given that one of the PCBs would contain wireless charging circuity the another one - MCU, some EEPROM and passives? Solid ground plane and no components directly above the motor? No polygons nor traces at all across the motor area?


Thank you for your time,

Edmunds

 

DC motor with carbon brushes? That would be a good reason to worry.
The usual capacitors must be installed near the motor to reduce changes in the power supply voltage. Provide a completely separate ground line to keep the motor current out of the MCU ground line. I would consider a metal tube around the motor to suppress radiated energy, but only if the measured results show you need shielding.

I am not the expert in this area. Other people will surely come up with other, valid methods.

 

Is the motor mounted directly to the PCB?

 

That is such a small motor I would not see any problem, other than accessibility.
Max.