Datasheet

Data Sheet
BMA456
Page 20
BST-BMA456-DS000-01 | Version 1.1 | October 2017 Bosch Sensortec
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Note: Specifications within this document are subject to change without notice.
4.4. Sensor Data
Acceleration Data
The width of acceleration data is 16 bits given in two´s complement representation in the registers
DATA_8 to DATA_13. The 16 bits for each axis are split into an MSB upper part and an LSB lower part.
Reading the acceleration data registers shall always start with the LSB part. In order to ensure the
integrity of the acceleration data, the content of an MSB register is locked by reading the corresponding
LSB register (shadowing procedure).
Filter Settings
The accelerometer digital filter can be configured through the Register ACC_CONF.
Note:
Illegal settings in configuration registers will result in an error code in Register ERR_REG. The content
of the data register is undefined, and if the FIFO is used, it may contain no value.
Accelerometer data processing for performance mode
Performance mode is enabled with ACC_CONF.acc_perf_mode=0b1. In this power mode, the
accelerometer data is sampled at equidistant points in the time, defined by the accelerometer output
data rate parameter ACC_CONF.acc_odr. The output data rate can be configured in one of eight
different valid ODR configurations going from 12.5 Hz up to 1600Hz.
The filter bandwidth shows a 3db cutoff frequency shown in the following table:
Table 12: 3dB cutoff frequency of the accelerometer according to ODR with normal filter mode
Accelerometer ODR [Hz]
12.5
25
50
100
200
400
800
1600
3dB Cutoff frequency [Hz]
5.06
10.12
20.25
40.5
80
162
(155 for
Z axis)
324
(262 for
Z axis)
684
(353 for
Z axis)