Total Deviation
Total deviation from the ideal theoretical transfer function across the entire operating range of a converter. Quantifying adc absolute accuracy requires summing all individual error components including offset and integral nonlinearity. The result identifies the maximum possible error at any point across the full scale range.
Performance depends on the reference voltage stability.
Error Calculation
Maximum error limits are determined by calculating the root sum square of all contributing factors or by using a simple additive limit for a worst case specification. Measured values of the adc absolute accuracy indicate the closeness of the digital output to the true value of the analog input voltage. Manufacturers specify this limit at a defined temperature and supply voltage.
Calibration Protocol
Traceable voltage sources provide the standard against which the conversion results are verified during production testing. Adjusting the adc absolute accuracy often involves trimming internal resistors or using digital calibration registers. Environmental factors like temperature drift can increase the total error beyond initial specifications.
Component Influence
Integral nonlinearity usually forms the largest irreducible part of the total error budget in high resolution systems. Small variations in the reference source cause proportional shifts in the adc absolute accuracy across all codes. Systematic errors are typically corrected via software look up tables.
