Patent ID: 8941518
Filing Date: 2015-01-27
Classification: H03M

Abstract:
1. In a pipeline analog-to-digital converter having at least a first channel and a second channel connected in parallel for sampling an input analog signal, each channel including one or more serially connected analog-to-digital pipeline stages and a back-end analog-to-digital converter receiving an output voltage from a pipeline stage, a method for determining transition step size for use in calibration comprising the steps of: (a) selecting a given output code or a range of output codes from the second channel corresponding to a particular input voltage of the input analog signal, said given output code or range of output codes selected to be within a transition band of a comparator in a first pipeline stage of the first channel; (b) each time the given output code or an output code within the range of output codes from the second channel is detected during sampling of the input analog signal, identifying a corresponding output code from the back-end analog-to-digital converter of the first channel and a corresponding output code from the first pipeline stage of the first channel; (c) determining whether the output codes of the back-end analog-to-digital converter of the first channel correspond to either a first output code or a second output code from the first pipeline stage of the first channel; (d) performing a statistical analysis of output codes from the back-end analog-to-digital converter of the first channel corresponding to the first and second output codes from the first pipeline stage of the first channel; and (e) determining a transition step size based on the difference between the output codes from the back-end analog-to-digital converter of the first channel corresponding to the first and second output codes from the first pipeline stage of the first channel.