BMA250 Bosch Sensortec, BMA250 Datasheet - Page 51

• Manufacturer Part Number: BMA250
• Description: 3-AXIS ACCELEROMETER DIGITAL I/F
• Manufacturer: Bosch Sensortec
• Series: -r

Specifications of BMA250

• Featured Product: BMA250 - Digital, Triaxial Acceleration Sensor
• Axis: X, Y, Z
• Acceleration Range: ±2g, 4g, 8g, 16g
• Sensitivity: 256LSB/g, 128LSB/g, 64LSB/g, 16LSB/g
• Voltage - Supply: 1.62 V ~ 3.6 V
• Output Type: I²C™, SPI™
• Bandwidth: 8Hz ~ 1kHz
• Interface: I²C, SPI
• Mounting Type: Surface Mount
• Package / Case: 12-VQFN
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With: 828-1024 - BMA250 DAUGHTERCARD FOR DEV KIT
• Other names: 828-1023-2

Writing ´1´ (´0´) to (0x36) hp_x_en enables (disables) slow offset compensation for the x-axis.
Default value for each of (0x36) hp_x_en, (0x36) hp_y_en, and (0x36) hp_x_en is ´0´,
respectively.
Register (0x37) contains settings for the offset compensation in general, and for slow offset
compensation. (0x37) offset_target_z sets the target value for the offset compensation of the z-
axis.
(0x37) offset_target_y sets the target value for the offset compensation of the y-axis.
(0x37) offset_target_x sets the target value for the offset compensation of the x-axis.
The settings for (0x37) offset_target_x, (0x37) offset_target_y, and (0x37) offset_target_z are
´00b´ (0 g), ´01b´ (+1 g), ´10b´ (-1 g), and ´11b´ (0 g). Default value of each of (0x37)
offset_target_x, (0x37) offset_target_y, and (0x37) offset_target_z is ´00b´, respectively.
(0x37) cut_off defines the number of samples for comparison by the slow offset compensation.
The settings for (0x37) cut_off are ´0´ (8 samples) and ´1´ (16 samples). The default value of
(0x37) cut_off is ´0´.
Register (0x38) contains the compensation value for filtered data for the x-axis. The contents of
each of the registers (0x38) to (0x3D) is added to the corresponding acceleration data; it can be
set either automatically by one of the implemented compensation algorithms or manually. These
registers are image registers of registers in the EEPROM; the content of the EEPROM is copied
to them after every reset.
Rev. 1.0
© Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such
as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany.
Note: Specifications within this document are subject to change without notice.
Table 63: Offset compensation, fast offset compensation, register (0x36)
Table 64: Offset compensation, slow offset compensation, register (0x37)
Table 65: Filtered data compensation for the x-axis, register (0x38)
reserved
filt_x<7>
offset_
_reset
offset
Bit 7
Bit 7
Bit 7
offset_tar
get_z<1>
filt_x<6>
trigger<1
offset_
Bit 6
Bit 6
Bit 6
cal_
>
offset_tar
get_z<0>
filt_x<5>
trigger<0
offset_
Bit 5
Bit 5
Bit 5
cal_
>
Page 51 / not for publishing
get_y<1>
offset_tar
filt_x<4>
offset_
cal_rdy
Bit 4
Bit 4
Bit 4
Data sheet
BMA250
offset_tar
get_y<0>
reserve
filt_x<3>
offset_
Bit 3
Bit 3
Bit 3
d
hp_z_en
offset_tar
get_x<1>
filt_x<2>
Bit 2
offset_
Bit 2
Bit 2
hp_y_en
offset_tar
get_x<0>
filt_x<1>
Bit 1
offset_
Bit 1
Bit 1
Bosch Sensortec
03 March 2011
hp_x_en
filt_x<0>
cut_off
offset_
Bit 0
Bit 0
Bit 0