BMA255 datasheet(22/119 Pages) BOSCH

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BMA255

Data sheet

Page 22

BST-BMA255-DS004-05 | Revision 1.2 | August 2014

Bosch Sensortec

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.

The public offset compensation registers (0x38) offset_x, (0x39) offset_y, (0x3A) offset_z are

images of the corresponding registers in the NVM. With each image update (see section 4.6

Non-volatile memory for details) the contents of the NVM registers are written to the public

registers. The public registers can be over-written by the user at any time. After changing the

contents of the public registers by either an image update or manually, all 8bit values are

extended to 12bit values for internal computation. In the opposite direction, if an internally

computed value changes it is converted to an 8bit value and stored in the public register.

Depending on the selected g-range the conversion from 12bit to 8bit values can result in a loss

of accuracy of one to several LSB. This is shown in figure 5.

In case an internally computed compensation value is too small or too large to fit into the

corresponding register, it is saturated in order to prevent an overflow error.

By writing ´1´ to the (0x36) offset_reset bit, all offset compensation registers are reset to zero.

BMA255 데이터시트(PDF) 22 Page - Bosch Sensortec GmbH