Sensors
Freescale Semiconductor 2
MMA8450Q
Contents
1 Block Diagram and Pin Description ..................................................................................................................................3
1.1 Block Diagram .............................................................................................................................................................3
1.2 Pin Description ............................................................................................................................................................3
1.3 Soldering Information ..................................................................................................................................................5
2 Mechanical and Electrical Specifications .........................................................................................................................6
2.1 Mechanical Characteristics .........................................................................................................................................6
2.2 Electrical Characteristics .............................................................................................................................................7
2.3 I
2
C Interface Characteristic .........................................................................................................................................8
2.4 Absolute Maximum Ratings .........................................................................................................................................9
3 Terminology .......................................................................................................................................................................10
3.1 Sensitivity ..................................................................................................................................................................10
3.2 Zero-g Offset .............................................................................................................................................................10
3.3 Self-Test ....................................................................................................................................................................10
4 Modes of Operation ...........................................................................................................................................................10
5 Functionality ......................................................................................................................................................................11
5.1 Device Calibration .....................................................................................................................................................11
5.2 8-bit or 12-bit Data .....................................................................................................................................................11
5.3 Internal FIFO Data Buffer ..........................................................................................................................................11
5.4 Low Power Mode .......................................................................................................................................................11
5.5 Auto-Wake/Sleep Mode ............................................................................................................................................12
5.6 Freefall and Motion Detection ...................................................................................................................................12
5.6.1 Freefall Detection ...........................................................................................................................................12
5.6.2 Motion Detection ............................................................................................................................................12
5.7 Transient Detection ...................................................................................................................................................12
5.8 Orientation Detection .................................................................................................................................................13
5.9 Interrupt Register Configurations ..............................................................................................................................14
5.10 Serial I
2
C Interface ....................................................................................................................................................14
5.10.1 I
2
C Operation .................................................................................................................................................15
6 Register Descriptions .......................................................................................................................................................17
6.1 Data Registers ...........................................................................................................................................................19
6.2 32 Sample FIFO ........................................................................................................................................................21
6.3 Portrait/ Landscape Embedded Function Registers ..................................................................................................25
6.4 Freefall & Motion Detection Registers .......................................................................................................................29
6.5 Transient Detection Registers ...................................................................................................................................32
6.6 Tap Detection Registers ............................................................................................................................................34
6.7 Auto-Sleep Registers ................................................................................................................................................36
6.8 User Offset Correction Registers ..............................................................................................................................40