BMA250 Bosch Sensortec, BMA250 Datasheet - Page 27

• 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

(0x16) s_tap_en and (0x16) d_tap_en, then only (0x16) d_tap_en keeps the value ´1´ and the
double tap interrupt is enabled.
The status of the single tap interrupt is stored in bit (0x09) s_tap_int, the status of the double tap
interrupt is stored in bit (0x09) d_tap_int.
The slope threshold for detecting a tap event is set by bits (0x2B) tap_th. The meaning of
(0x2B) tap_th depends on the range setting. 1 LSB of (0x2B) tap_th corresponds to a slope of
62.5mg in 2g-range, 125mg in 4g-range, 250mg in 8g-range, and 500mg in 16g-range.
In figure 7 the meaning of the different timing parameters is visualized:
The parameters (0x2A) tap_shock and (0x2A) tap_quiet apply to both single tap and double tap
detection, while (0x2A) tap_dur applies to double tap detection only. Within the duration of
(0x2A) tap_shock any slope exceeding (0x2B) tap_th after the first event is ignored. Contrary to
this, within the duration of (0x2A) tap_quiet no slope exceeding (0x2B) tap_th must occur,
otherwise the first event will be cancelled.
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.
tap_th
slope
single tap detection
double tap detection
tap_shock
1st tap
Figure 7: Timing of tap detection
tap_quiet
Page 27 / not for publishing
Data sheet
BMA250
12.5 ms
tap_shock
2nd tap
tap_dur
tap_quiet
12.5 ms
Bosch Sensortec
03 March 2011
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