I need to use the LSM6DS3 at 5Hz and lowest power consumption possible. How long does it takes from power down mode to valid data and back to power down (i.e. how much wake up time does it requires for one point measurement)? Thansk!

[Eleon BORLINI]

Hi @PBitt.1​ , please note that the minimum output data rate (ODR) for the LSMDS3 device is 12.5Hz, as described in the datasheet p.51... I don't know however if you may want to manage a 5Hz-communication by filling the FIFO at 26Hz and then averaging on 5 samples, but you will increase the power consumption with respect to the 12.5Hz ODR case.

Please note then that you can refer to p.33 of the application note AN4650 for a detailed description of the accelerometer and gyroscope turn-on/off time: all the details are specified in a dedicated table.

Btw, which kind of measure would you like to implement? A quasi-static acceleration measure (e.g. tilt) or the request is for the lowest possible power consumption? I n this second case, I would ask you to run the device in low power mode (XL_HM_MODE bit in CTRL6_C (15h) set to 1 and G_HM_MODE bit in CTRL7_G (16h) set to 1 too, see datasheet p.29). Regards

[PBitt.1]

Dear Eleon,

Thank you for the reply.

I had not seem the application note. Am I right to say it can take up to 80ms from power down to normal mode? I noticed the time from sleep mode to normal mode is much faster, but I could not find the current consumption in sleep mode in the datasheet or in the application note.

I am using it for measuring tree biomechanis. The equipments will be installed in top of trees to monitor the swinging moviment with wind so both tilt and acceleration are important.

I do not actually need to have exactly 5 Hz. I need to have at least 4 samples per second to be able to capture the signal, if there is more I can either average or discard. The main problem is I need very low power, as the equipment should be able to stay active for several months withouth maintenance. For this, I intend to have fast alternation of data sampling (10-30ms), followed by a low power state (220-240ms). This is the reason why fast wake up from power down is critical.

Thank you again,

Paulo.