1. what is the Inaccuracy of the data sampling rate? 2. What is the correlation of temperature with data accuracy?

HHP.1 · ‎2023-03-29

I am using LIS2DTW12 MEMS,

1. I configured this sensor in continuous mode.

2. Set the FIFO threshold to 16 samples.

3. Selected ODR register value is 100.

4 Selected Low power 1 mode.

Expected:

Periodic interrupt from FIFO must happen every 160ms. But I am getting FIFO interrupt at ~158.4ms.

Could you please explain the cause of this time drift and how to fix it?

Note: our operating temperature range is -5 to 60 degrees C.

Federica Bossi · ‎2023-04-12

Hi @HHP.1 ,

Welcome to ST Community!

Looking at the data, a FIFO interrupt at 158.4 corresponds to measure an ODR of about 99Hz.

We measure the ODR accuracy only on characterization data and so we can't guarantee min-max values in production but measuring 99Hz instead of 100Hz is acceptable according to our data.

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HHP.1 · ‎2023-04-12

Hello @Federica Bossi ,

Thank you for your response.

Is there any way to accumulate this frequency drift?

Can you give detailed information on ODR accuracy in terms of %error?

Federica Bossi · ‎2023-04-13

Hi @HHP.1 ,

A drift over time is not expected.

I can't give you detailed information because ODR Accuracy is not a tested parameter in production but according to characterization tests on a limited samples of data you can consider approximately up to 10%.

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