Datasheet

Preliminary Data Sheet

BMA400

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Confidential

BST-BMA400-DS000-00 | Version 0.1 | November 2017 Bosch Sensortec

BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany.

Note: Specifications within this document are subject to change without notice.

Wake-up interrupt on activity

If in low-power mode, BMA400 will wake up when the conditions as defined by the configuration

registers are fulfilled. The wake-up can be used for the wake-up of the external MCU using interrupt

mapping or/and for changing the BMA400 power mode into normal mode to evaluate the acceleration

data more accurately for complex/advanced interrupts or/and store the data in the FIFO for advanced

processing on the external MCU.

The Low-power wake-up function evaluates acceleration data and is set as soon as the value of the

sampled data exceeds the preconfigured acceleration threshold. The comparison of the current

acceleration value with a reference is configurable between relative reference (last sampled value

stored in the register) and absolute reference (the reference values are set once and not changing

after each acceleration conversion). The delay between two data conversions is 40ms (25Hz

conversion ODR in Low-power). The Low-power wake- up function is activated by setting

AUTOWAKEUP_1.wkup_int bit. The wakeup status is available in INT_STAT0.wkup_int.

When woken up, an interrupt can be generated and mapped to the interrupt pins.

The Low-power wake-up function supports following configurations:

 Selectable axis for wake-up: the Low-power wake-up function supports independent

activation/deactivation of each acceleration axis for function evaluation. This is performed by

setting the bits WKUP_INT_CONGIF0.wkup_X/Y/Z_en accordingly.

Confidential and under NDA

Seeed Studio

Confidential and under NDA

Seeed Studio

Confidential and under NDA