Smb365 Low-Power Mode In Independent Interrupt Conditions - Bosch SMB365 Application Note

Multi sensor, wireless demo-board

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Table Of Contents

Table of Contents

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Select Low-Power Mode [20]

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Select any acceleration range [21]

•

Select Global Interrupt Mode [22]

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Put in global Hysteresis and Threshold digits [23]

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Start data acquisition [8]

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Accelerate, roll or tilt the BlueBox board while watching the interrupt LED [25]

Notes:

The triggering of an interrupt depends, in the first instance, on global Threshold value settings.

The global Threshold can be assumed as the interrupt "switch-on" level which must be

exceeded from at least one axis dependent acceleration signal. If any acceleration signal

exceeds this value, an interrupt will be activated. If all signals are below the Threshold value

again, the interrupt will be deactivated, provided that the Hysteresis value is set to zero, e.g.:

LED [25] = 1 if LSB

LED [25] = 0 if LSB

In addition to the global Threshold value a global Hysteresis value can also be set. The

Hysteresis can be assumed as the interrupt "switch-off" level, which must be under-run again

from all signals, to deactivate the triggered interrupt. It relates directly to the before set

Threshold value by a mathematical subtraction. The following example shows how to set up the

global Threshold and Hysteresis values. The calculation corresponds to the 2g operation mode,

e.g.:

LED [25] = 1 if LSB

LED [25] = 0 if LSB

Threshold:

Hysteresis:

If Hysteresis is equal or above Threshold, the interrupt functionality will be disabled. For a total

reset of the sensor internal interrupt information just switch to standby mode [20] and continue.

4.3.3