can we place the microcontroller near by inductor. can the magnestic feild affect the concontroller????

 

can we place the microcontroller near by inductor. can the magnestic feild affect the concontroller????

Oh yes... it most definitely can affect an MCU. There have been many papers written on the subject, and it's almost as much an art as it is a science. A strong EMI field can easily cause an MCU to do very strange things, including resetting itself sporadically. I have some personal experience with that.

http://www.ti.com/lit/an/snoa382/snoa382.pdf
http://electronics.stackexchange.co...no-resetting-hanging-due-to-sparks-in-ac-line
http://www.microchip.com/forums/m66002.aspx
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Thanks a lot for the reply.I just want to know the recommended immunity level .the separation between micro controller and inductor we are providing 1cm as the separation between micro controller and inductor. And the inductance is 400 uH,switching at 100000 with an average current of 7.5A(peak current of 11 A).Could you please help me.
thanks

 

Thanks a lot for the reply.I just want to know the recommended immunity level .the separation between micro controller and inductor we are providing 1cm as the separation between micro controller and inductor. And the inductance is 400 uH,switching at 100000 with an average current of 7.5A(peak current of 11 A).Could you please help me.
thanks

I'm afraid that calculating such scenario is beyond my capabilities. The results of the setup you've described depend on many things, including PCB layout and component geometry (is the inductor in parallel, or perpendicular to the MCU?), and that's not even mentioning its surroundings. There are simulators out there for this sort of thing that cost something in the order of tens of thousands of dollars, if not more.

As a rule of thumb, you want the inductor as far as possible from the MCU, and the EMI produced by it at right angles to its I/O and power traces. You also want power and ground planes that call for at least 4 layers on the PCB. Another thing is that 1 cm is usually not enough. A separation of at least 8 or 10 cm would be in order.

@OBW0549, you might find this question interesting.

 

The type of inductor is important. An axial air core inductor is more problematical than a toroid.