Datasheet

MMA8652FC
Sensors
Freescale Semiconductor, Inc. 17
Figure 7. Landscape-to-Portrait transition trip angles
The MMA8652FC orientation detection algorithm confirms the reliability of the function with a configurable Z-lockout angle.
Based on the known functionality of linear accelerometers, it is not possible to rotate the device about the Z-axis, to detect change
in acceleration at slow angular speeds. The angle at which the device no longer detects the orientation change is referred to as
the “Z-lockout angle” (see Figure 8). The device operates down to 14° from the flat position.
.
Figure 8. Z-Tilt angle lockout transition
PORTRAIT
Landscape-to-Portrait
90
°
Trip Angle = Midpoint + hysterisis value
0° Landscape
PORTRAIT
Portrait-to-Landscape
90
°
Trip Angle = midpoint - hysteresis value
0° Landscape
UPRIGHT
NORMAL
90°
Z-LOCK
0° FLAT
DETECTION
REGION
LOCKOUT
REGION
When lifting the device upright from the
flat position, orientation detection will be
active for orientation angles greater than
a user-configurable value.
The default angle is 29° from flat, but the
angle can be set as low as 14°.