I just used my eval. board and BMI270 shuttle board that has BMM150 installed. From the Windows GUI SW plot below, it can be seen that BMM150 z axis data (in red color) doesn't go beyond +/-2500uT when I place a strong magnet nearby. After I remove the strong magnet, BMM150 goes back to normal immediately. By the way, the GUI SW uses BMM150 API/driver on the Github.
Therefore, in theory when external magnet field is beyond BMM150 z axis +/-2500uT range, BMM150 z axis raw data should be fixed or clamped for saturation. However, if BMM150 z axis still outputs raw data when the external magnetic field is beyond +/-2500uT range and the API/driver still outputs values that are outside of +/-2500uT range, then BMM150 is still working but the performance is not guaranteed because each BMM150 is calibrated, trimmed and tested under +/-2500uT range in Bosch factory.
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