What data does a LIS2dh12 accelero-meter compare to generate an interrupt? Is it a data itself or the delta of the reading?

[KChoo]

I have a product that uses LIS2DH12 to detect the lack of motion and generates the interrupt. I configured the INT2_CFG(34h) to 15h, INT2_THS(36h) to 0Fh, INT2_DURATION(37h) to 20h. Reading INT2_SRC(35h) gives the response as XXX1X1X1 when the product is lack of motion. What I do not understand is that what happened to the gravitational acceleration? Could the lack of motion detection fail if the sensor is orientated at 45 degree to all axes (all X, Y, Z axis)? The gravitational force appear in all axes (bigger than the threshold for the interrupt causes the failure in detection. Or it is actually the delta of the reading is being used to generate the interrupt?

[Eleon BORLINI]

Hi, the internal circuitry of the accelerometer compares the dataout value to the threshold, giving an interrupt if the value is above or below a certain threshold (depending on the INT2_CFG value). Constant acceleration (and gravity itself) is included in the dataout value, However, if you are interested only in AC axl components of the sensor and you don't mind some little settling times, you can use the High Pass filter (HPCFx bits in CTRL_REG2 (21h)), which is before the interrupt detection source. Regards