BMA140

Data sheet

Triaxial, analog acceleration sensor

Bosch Sensortec

Rev. 1.1

Page 13

04 April 2008

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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.

4.6

Polarity of the acceleration output

If the sensor is accelerated into the indicated directions, the corresponding channels will deliver

a positive acceleration signal (dynamic acceleration).

Example: If the sensor is at rest or at uniform motion in a gravity field according to the figure

given below, the output signals are:

• ± 0g for the x channel

• ± 0g for the y channel

• + 1g for the z channel

+z

+x

top side

+y

gravity vector

The following table lists all corresponding output signals on Ax, Ay, and Az while the sensor is

at rest or at uniform motion in a gravity field under assumption of a top down gravity vector as

shown above.

Sensor Orientation

(gravity vector )

Output Signal Ax

0g / 1.5V

+1g /

1.8V

0g / 1.5V

-1g / 1.2V

0g / 1.5V

0g / 1.5V

Output Signal Ay

-1g / 1.2V

0g / 1.5V

+1g /

1.8V

0g / 1.5V

0g / 1.5V

0g / 1.5V

Output Signal Az

0g / 1.5V

0g / 1.5V

0g / 1.5V

0g / 1.5V

+1g /

1.8V

-1g / 1.2V

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