BMA400 and magnetic fields

[AndrewO]

I am looking at the Bosch BMA400  for a medical application, but the PCBA that this sensor will be located on will be within several centimeters  of a permanent magnet. The mounting instructions for Bosch Accelerometers (document number BST-MAS-HS000) states "Avoid mounting (and operation) of the sensor in the vicinity of strong magnetic, strong electric and/or strong infrared radiation fields (IR)."  The BMA400  does not have a magnetometer, so does this recommendation still apply?   If so , what is the maximum acceptable magnetic field intensity  for the sensor to work correctly?

[FAE_CA1]

Hi,

Thanks for your inquiry.

It is true that BMA400 should be placed as far away from the strong magnet as possible, because there is mechanical moving MEMS structure and ASIC electrical circuits inside BMA400. But a few centimeters away from the magnet should be sufficient. We don't have the maximum acceptable magnetic field intensity value for the sensor to work correctly. But you can do your own evaluation by using BMA400 shuttle board and APP3.0 base board and DD2.0 GUI SW. When you move the strong magnet close to BMA400 you can check if BMA400 data is changed or still stays the same.

Thanks.

[bvn123]

Hi, I use BMA280 on a separated PCB. A customer asks to glue to the bottom of this PCB a permanent magnet (strength 100...300 mT) to provide quick mount of the PCB on the steel surfaces.

AndrewO, have You made the tests to check possible influence of the permanent magnetic field on BMA400 drift, stability, long term influence and so on?

May You report the results of observations?

Thanks.