Datasheet

4.6 Terminology
4.6.1 Sensitivity
Linear acceleration sensitivity can be determined, for example, by applying 1 g acceleration to the device.
Because the sensor can measure DC accelerations, this can be done easily by pointing the selected axis towards
the ground, noting the output value, rotating the sensor 180 degrees (pointing towards the sky) and noting the
output value again. By doing so, ±1 g acceleration is applied to the sensor. Subtracting the larger output value
from the smaller one, and dividing the result by 2, leads to the actual sensitivity of the sensor. This value changes
very little over temperature and over time. The sensitivity tolerance describes the range of sensitivities of a large
number of sensors (see Table 2).
An angular rate gyroscope is a device that produces a positive-going digital output for counterclockwise rotation
around the axis considered. Sensitivity describes the gain of the sensor and can be determined by applying a
defined angular velocity to it. This value changes very little over temperature and time (see Table 2).
4.6.2 Zero-g and zero-rate level
Linear acceleration zero-g level offset (TyOff) describes the deviation of an actual output signal from the ideal
output signal if no acceleration is present. A sensor in a steady state on a horizontal surface will measure 0 g on
both the X-axis and Y-axis, whereas the Z-axis will measure 1 g. Ideally, the output is in the middle of the dynamic
range of the sensor (content of OUT registers 00h, data expressed as 2’s complement number). A deviation from
the ideal value in this case is called zero-g offset.
Offset is to some extent a result of stress to MEMS sensor and therefore the offset can slightly change after
mounting the sensor onto a printed circuit board or exposing it to extensive mechanical stress. Offset changes
little over temperature, see “Linear acceleration zero-g level change vs. temperature” in Table 2. Mechanical
characteristics. The zero-g level tolerance (TyOff) describes the standard deviation of the range of zero-g levels of
a group of sensors.
Zero-rate level describes the actual output signal if there is no angular rate present. The zero-rate level of precise
MEMS sensors is, to some extent, a result of stress to the sensor and therefore the zero-rate level can slightly
change after mounting the sensor onto a printed circuit board or after exposing it to extensive mechanical stress.
This value changes very little over temperature and time (see Table 2. Mechanical characteristics).
LSM6DSO
Terminology
DS12140 - Rev 2
page 16/172