relative accuracy
PrintA measure in LSB of the accuracy of an ADC. It includes all non-linearity and quantization errors. It does not include offset and gain errors of the circuitry feeding the ADC.
A measure in least significant bits (LSBs) of the nonlinear errors associated with an A/D converter or DAQ system. Relative accuracy is the worst-case deviation from the ideal DAQ board transfer function, a straight line. A relative accuracy test is run by linearly sweeping the input from minus full scale to plus full scale, and comparing the average of the digitized values to the values of an endpoint-fit straight line, created from an endpoint fit of the data. Relative accuracy includes all nonlinearity and quantization errors, but does not include offset and gain errors of the circuitry feeding the ADC. The relative accuracy is measured in least significant bits (LSBs). The lower the relative accuracy, the better the linearity of the product. Practically, a good DAQ product will have a relative accuracy of within ±1 LSB. The relative accuracy is a very important specification because it tells how accurately the continuous analog input range is converted to discrete digital values.
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