Trimming algorithm for pipeline A/D converter using integrated non-linearity measurement

摘要

A trimming algorithm for a pipeline A/D converter includes the step of trimming the input sampling capacitor on each of the gain stages for each stage of the pipeline A/D converter. The input thereof is swept from a minimum to a maximum analog voltage and then the integral non-linearity (INL) of the A/D converter determined. The maximum transitions are then examined to determine which transitions are associated with which stage. The transitions for a given stage then constitute the gain error for these stages. The trim values are determined from this gain error and then the trim values incorporated into each of the gain stages.