Please let me know your advice whethere below my understanding of ADXL362 wake up mde is correct or not.
1: Wake up mode switches between standby and measurement mode
2: Filter settings ( ODR/2 or ODR/4) at wake up mode is the same as regsiter settings.
3: Regarding above 2, if we would like to reduce noise level at wakeup mode, we should set ODR settings to low ODR ( for example, 12.5Hz).
I do not understand how the noise calculation at wake up mode is estimated . ( 6Hz/2 or 6Hz/4 or set ODR/2 or set ODR/4)
Please let me know your advice.
Thanks for the question.
1. You can understand Wakeup mode as a switch between Stanby and Measurement mode.
2. In Wakeup mode, the ODR is set to 400Hz and filter BW is set to 100/200Hz. This is a fixed setting and the data is only sampled at ~6Hz. Based on the data we have, the std. dev in (LSBs) for X and Y axes are roughly 8LSBs, and roughly 13LSBs for Z axis in wakeup mode.
Thank you for your answer.
I understand that I can set 100Hz or 200Hz at wake up mode using HALF_BW resiter setting.
Is my understanding correct ?
Could you update my question ?
Your answer says that X and Y are rouly 8LSBs.
I think that this noise level is estimated at 200Hz and 2g settings.
( 550ug*root (200Hz)= 7778ug = about 8LSB .)
So I would like to confirm if I can select not 200Hz but 100Hz settings using HALF_BW register for reduesing noise
In Wakeup mode, the ODR is fixed at 400Hz, even you change it to other numbers in the register setting.
The ODR is fixed at 400Hz in wake up mode.
I think that HALF_BW register does not affect ODR and affects the BW of filter only .
Then can I change the filter from ODR/2 to ODR/4 usng HALF_BW register ?
I would like to reduce noise level by changing the filter from ODR/2( 200Hz ) to ODR /4 (100Hz).
Yes, the HALF_BW affect BW of the filter. But what I mean is it sets the BW to either 200Hz of 100Hz but that doesn't help the antialiasing since the sample rate of the sensor is 6Hz in wakeup mode.
I understood your advice.