US 6,476,741 B2Granted

Method and system for making optimal estimates of linearity metrics of analog-to-digital converters

AssigneeGeorgia Tech Research Corporation

InventorsSasikumar Cherubal, Abhijit Chatterjee

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Abstract

A method and system for making optimal estimates of linearity metrics of analog-to-digital converters. A model building phase and a production test strategy are employed. During the model-building phase, a linear model an analog-to-digital converter is constructed from a set of accurately measured transition code voltages for a set of training analog-to-digital converters. During a production test of an individual analog-to-digital converter, a ramp test signal is applied to the individual analog-to-digital converter, a histogram of codes is produced, and the transition code voltages for the individual analog-to-digital converter are estimated from the resulting histogram. Linearity characteristics of the individual analog-to-digital converter may then be computed.

Claims17

Dependent claims

A method for making optimal estimates of linearity metrics of an analog-to-digital converter, comprising:

constructing a statistical model of transition code voltages of the analog-to-digital converter based on application of a test input signal to a plurality of training analog-to-digital converters of like kind and measurements of the transition code voltages of said plurality of training analog-to-digital converters, said statistical model being adapted to produce an estimate of the transition code voltages for an individual analog-to-digital converter in response to a plurality of scaling inputs;
generating said scaling inputs by applying said test signal as an input to said individual analog-to-digital converter, measuring the transition code voltages thereof, and computing a least-squares estimate of said scaling inputs given said measured transition code voltages;
and
applying said generated scaling inputs to said statistical model to produce a set of estimated transition code voltages of said individual analog-to-digital converter that are more accurate than said measured transition code voltages thereof.

1 more element

A system for making optimal estimates of linearity metrics of a test analog-to-digital converter, comprising:

a test signal generator for producing a test signal for input to the test analog-to-digital converter;
a processor for receiving both said test signal and digital codes produced by the test analog-to-digital converter in response to said test signal, said processor including a component for determining the mean values of the transition code voltages of the test analog-to-digital converter, a component for determining the variance of the errors in the transition code voltages of the test analog-to-digital converter from said mean values of the transition code voltages of the test analog-to-digital converter, the variance of the errors in the transition code voltages of the test analog-to-digital converter, a set of predetermined data representing the variance of transition code voltages in a training plurality of like analog-to-digital converters and a statistical model of the test analog-to-digital converter based on said training plurality of like analog-to-digital converters, and a component for computing estimates of the transition code voltages of the test analog-to-digital converter.

Dependencies are inferred from the claim text.