BMA250 Bosch Sensortec, BMA250 Datasheet - Page 15

• 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

The current consumption of the BMA250 can be calculated according to this formula:
When making an estimation about the length of the wake-up phase t
t
wake-up phase all analog modules are held powered-up, while during the sleep phase most
analog modules are powered down. As a consequence, a wake-up time of less than 1ms (typ.
value 0.8ms) is needed to settle the analog modules in order to get reliable acceleration data.
Table 7 gives an overview of the resulting average supply currents I
phase durations and a selected bandwidth of 1000Hz, assuming no interrupt is active and thus
only one sample per wake-up phase is taken:
Rev. 1.0
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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.
w_up
, has to be considered. Therefore, t
Table 6: Sleep phase duration settings
sleep_dur
(0x11)
0000b
0001b
0010b
0011b
0100b
0101b
0110b
0111b
1000b
1001b
1010b
1011b
1100b
1101b
1110b
1111b
Page 15 / not for publishing
active
Data sheet
BMA250
I
= t
DDlp
Sleep Phase
ut
Duration

+ t
100ms
500ms
0.5ms
0.5ms
0.5ms
0.5ms
0.5ms
0.5ms
10ms
25ms
50ms
t
1ms
2ms
4ms
6ms
t
sleep
1s
w_up
sleep
, where t

I
t
sleep
DDsm


t
t
active
ut
active
is given in table 8. During the

DDlpe
I
DD
active
.
for the different sleep
, the wake-up time,
Bosch Sensortec
03 March 2011