BMA250 Bosch Sensortec, BMA250 Datasheet - Page 45

• 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

Register (0x21) contains the interrupt reset bit and the interrupt mode selection. Writing ´1´ to
(0x21) reset_int resets any latched interrupt.
The settings for (0x21) latch_int are ´0000b´ (non-latched), ´0001b´ (temporary, 250 ms),
´0010b´ (temporary, 500 ms), ´0011b´ (temporary, 1 s), ´0100b´ (temporary, 2 s), ´0101b´
(temporary, 4 s), ´0110b´ (temporary, 8 s), ´0111b´ (latched), ´1000b´ (non-latched), ´1001b´
(temporary, 500 s), ´1010b´ (temporary, 500 s), ´1011b´ (temporary, 1 ms), ´1100b´
(temporary, 12.5 ms), ´1101b´ (temporary, 25 ms), ´1110b´ (temporary, 50 ms), ´1111b´
(latched).
Default value of (0x21) latch_int is ´0000b´.
Register (0x22) contains the delay time definition for the low-g interrupt. The physical delay
time can be computed from the content of (0x22) low_dur according to:
delay [ms] = [(0x22) low_dur + 1] • 2 ms.
Possible delay times range from 2 ms to 512 ms. Default value of (0x22) low_dur is 0x09,
corresponding to a delay of 20 ms.
Register (0x23) contains the threshold definition for the low-g interrupt. An LSB of (0x23)
low_th corresponds to an actual acceleration of 7.81 mg. Therefore, the threshold ranges from 0
g to 1.992 g. Default value of (0x23) low_th is 0x30, corresponding to an acceleration of 375
mg.
Register (0x24) contains the low-g interrupt mode selection, the low-g interrupt hysteresis
setting, and the high-g interrupt hysteresis setting. Setting (0x24) low_mode to ´0´ (´1´) selects
´single´ mode (´sum´ mode). Default value is ´0´ (´single´ mode).
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 46: Interrupt reset bit and interrupt mode selection, register (0x21)
Table 47: Delay time definition for the low-g interrupt, register (0x22)
Table 48: Threshold definition for the low-g interrupt, register (0x23)
reset_int
dur<7>
th<7>
Bit 7
Bit 7
Bit 7
low_
low_
reserved
dur<6>
th<6>
Bit 6
Bit 6
Bit 6
low_
low_
reserved
dur<5>
th<5>
Bit 5
Bit 5
Bit 5
low_
low_
Page 45 / not for publishing
reserved
dur<4>
th<4>
Bit 4
Bit 4
Bit 4
low_
low_
Data sheet
BMA250
dur<3>
int<3>
latch_
th<3>
Bit 3
Bit 3
Bit 3
low_
low_
dur<2>
int<2>
latch_
th<2>
Bit 2
Bit 2
Bit 2
low_
low_
dur<1>
int<1>
latch_
th<1>
Bit 1
Bit 1
Bit 1
low_
low_
Bosch Sensortec
03 March 2011
dur<0>
int<0>
latch_
th<0>
Bit 0
Bit 0
Bit 0
low_
low_