BMA250 Bosch Sensortec, BMA250 Datasheet - Page 25

• 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

setting bits (0x20) int1_od / (0x20) int2_od to ´0´, the interrupt pin output type gets open-drive,
by setting the configuration bits to ´1´, the output type gets push-pull.
Remark: Due to their use for sub-mode selection in dedicated mode, the states of both INT pins
are not defined during the first 2 ms after power-up.
4.8.4 New data interrupt
This interrupt serves for synchronous reading of acceleration data. It is generated after storing a
new value of z-axis acceleration data in the data register. The interrupt is cleared automatically
when the next cycle of data acquisition starts. The interrupt status is ´0´ for at least 50μs.
The interrupt mode of the new data interrupt is fixed to non-latched.
It is enabled (disabled) by writing ´1´ (´0´) to bit (0x17) data_en. The interrupt status is stored in
bit (0x0A) data_int.
4.8.5 Any-motion (slope) detection
Any-motion detection uses the slope between successive acceleration signals to detect
changes in motion. An interrupt is generated when the slope (absolute value of acceleration
difference) exceeds a preset threshold. It is cleared as soon as the slope falls below the
threshold. The principle is made clear in figure 6.
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.
acceleration
slope_th
slope
INT
acc(t
0
−1/(2*bw))
Figure 6: Principle of any-motion detection
acc(t
slope_dur
slope(t
0
Page 25 / not for publishing
)
0
)=acc(t
slope_dur
Data sheet
0
BMA250
)−acc(t
0
−1/(2*bw))
time
time
time
Bosch Sensortec
03 March 2011