Manual sampling rate with LIS3DSH

Silas Zulliger · ‎2018-06-14

Posted on June 15, 2018 at 07:59

Dear Community,

In a multi-sensor application, we need to be able to use a fixed sampling rate, which can not be set in the LIS3DSH settings (200Hz, 400Hz, 800Hz, 1600Hz), e.g. 1kHz. My idea was now to use the highest available sampling rate of 1600Hz and start the sensor over SPI for a single conversion, then stop the sensor and start it again after 1ms (for 1kHz). Functional I dont' see a problem to implement this behaviour, but is the result effectively a coherent 1kHz data stream or is there a problem with the internal decimation/filtering? Does the sensor average the output values only for lower sampling rates, or also at the maximum setting of 1600Hz?

Many thanks for your help!

#mems #accelerometer #mems-accelerometer ##lis3dsh

Miroslav BATEK · ‎2018-06-19

Posted on June 19, 2018 at 16:22

I think your idea will not work. If you switch from power-down to 1600Hz it can take up to 1/ODR to get data. So you won't be able to synchronize the accelerometer with other sensors.