Oversampling - FXOS8700CQ

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Oversampling - FXOS8700CQ

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ekalyvio
Contributor II

What exactly is Oversampling Rate (OSR)? If for example I set an ODR of 100 Hz for the magnetometer at an OSR=7, does this mean that the magnetometer will gather 16 samples, process them somehow and of all these 16 samples will return 1 as an output? What kind of processing is happening? (eg. Is it used any kind of averaging function?) Is oversampling having some kind of latency in the data (meaning that for a movement, we have some kind of hysteresis until we detect it)?

Thank you very much

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TomasVaverka
NXP TechSupport
NXP TechSupport

Hello Efthymios,

The OSR determines the number of averaged samples. As you correctly stated, at an ODR of 100Hz and OSR = 7, 16 samples are gathered (the sampling rate is actually 1600Hz) and averaged. Table 203 summarizes all eight oversampling options which trade-off between resolution and current consumption at varying sample rates.

Table 203.JPG

Best regards,

Tomas

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