Hello everyone. We have developed a product with BMI160 as motion sensor of choice. For the last year it has only been used to collect data about motion. We only collect agregated data in form on min, max, everage values for g force. We noticed, that from time to time we get pikes and dips in the derrived values. Generally it constitues in on or 2 axis showing really high positive or negative values. We've verified that test units didn't have any motion that could cause such a chage. Current hypothysis is that the way BMI is powered is the source of the promblem. I've use referance design for i2c as primary data bus. Both VDD and VDDIO powered from the same source, which is IO pin of microcontroller. i2c bus is pulled up to 3.3V from the duch regulator. Maybe somebody had simmilar issue? This behaviour is only triggered if we power on/off a set of sensors on the same i2c buss, but we could never concistantly replicate this issue to trigger the osciloscope. It happens randomly. We've already tested changing power source for BMI – without any luck. In the image: WM on/of is when sensors on the i2c bus are turned on/off, and WM off means they are disconnected from the bus. min and max are values of the magnitude that is calculated from samples from all 3 axis.
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