SENSING DIRECTION AND OUTPUT RESPONSE
The following figure shows sensing direction and the
output response for 2g mode.
Top View
65 4 3 21
Direction of Earth's gravity field.*
7
14
8 9 10 11 12 13
XOUT @ 0g = $00
YOUT @ +1g = $3F
ZOUT @ 0g = $00
Side View
Top
Bottom
XOUT @ 0g = $00
YOUT @ 0g = $00
ZOUT @ +1g = $3F
Bottom
XOUT @ +1g = $3F
YOUT @ 0g = $00
ZOUT @ 0g = $00
13 12 11 10 9 8
14
7
1 234 56
XOUT @ -1g = $C1
YOUT @ 0g = $00
ZOUT @ 0g = $00
Top
XOUT @ 0g = $00
YOUT @ 0g = $00
ZOUT @ -1g = $C1
XOUT @ 0g = $00
YOUT @ -1g = $C1
ZOUT @ 0g = $00
* When positioned as shown, the Earth’s gravity will result in a positive 1g output.
Figure 18. Sensing Direction and Output Response at 2g Mode
Table 7. Acceleration vs. Output
FS Mode
2g Mode
4g Mode
8g Mode
Acceleration
-2g
-1g
0g
+1g
+2g
-4g
-1g
0g
+1g
+4g
-8g
-1g
0g
+1g
+8g
Output
$80
$C1
$00
$3F
$7F
$80
$E1
$00
$1F
$7F
$80
$F1
$00
$0F
$7F
Sensors
Freescale Semiconductor
MMA7455L
21