Data Acquisition Speed, Accuracy, and Resolution Specifications

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Data Acquisition Speed, Accuracy, and Resolution Specifications (1.39 MB)

The objective of this application note is to explain the trade-off between analog to digital sampling speed and accuracy, and the difference between accuracy and resolution.

One specification important to almost every data acquisition application is measurement accuracy. Studies show that data acquisition equipment users feel that the most important aspect of such systems is the accuracy and integrity of the data. Unfortunately, accuracy is often misunderstood or misinterpreted by users, and often exploited by instrument manufacturers. This confusion has developed because of the many ways that accuracy can be stated, and the tendency to equate resolution and accuracy in digital instruments.

It is important to consider the relationship of an A/D converter’s sampling speed on accuracy: more speed usually results in more random noise in your data. In using a faster instrument, you may not be able to recover the accuracy required for your application through either analog or digital filtering.

And don’t confuse accuracy and resolution. The resolution you buy in an A/D may not contribute anything to the usefulness of your data.