I design a battery powered BT Tag using LIS3DE. I want to detect movement as a trigger to transmit BT beacons. Which mode should be choose if I want to reduce the power consumption.

[John KUNG]

LIS3DE connects to BLE IC using I2C Bus and INT pins

Please state the mode according to time before and after the trigger.

Second, if I want to monitor 30 seconds after trigger to double check is it need to transmit BT beacons. May I use LIS3DE FIFO to storage data and just wake up BLE IC at the end to reduce power consumption. Or is there have other solution.

[Miroslav BATEK]

You can configure the sensor to ODR=10Hz (CTRL_REG1) with current consumption ~3uA and setup interrupt generator (IG1_CFG) to trigger interrupt if acceleration is higher than threshold (IG1_THS) for certain time (IG1_DURATION).

The FIFO has 32 items, so if you want to store 30s you would need to reconfigure the ODR to 1Hz and enable the FIFO (by a mcu) after the interrupt was triggered.