Digital linearization calibration for analog to digital converter
AssigneeMotorola, Inc.
InventorDanny T. Pinckley
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Abstract
A method and means are offered of providing of a calibrated output of a analog to digital converter. The method includes the steps of, and means for, generating a calibration table relating a calibrated output of the analog to digital converter and a detected output, and, upon determination of a need, providing, by reference to the calibration table, the calibrated output of the analog to digital converter corresponding to an detected output of the analog to digital converter.
Claims30
A method of providing a calibrated output of an analog to digital converter, such method comprising the steps of:
- generating a calibration table relating a calibrated output of the analog to digital converter and a detected output;
- interconnecting an output of a reference digital to analog converter to an input to the analog to digital converter;
- incrementally applying an input to the reference digital to analog converter from a minimum input value to a maximum input value;
- storing an average input value of the reference digital to analog converter, measured between changes in the detected output, as a calibrated output value of the analog to digital converter and corresponding detected output of the analog to digital converter in the calibration table;
- and, in response to an external analog signal input to the analog to digital converter being converted to a signal approximately equal to the stored detected output, providing, by reference to the calibration table, the stored calibrated output corresponding to the detected output as a calibrated digital output representation of the external analog signal.
A method of providing a calibrated output Of a composite analog to digital converter having a plurality of analog to digital converters, equal to a composite number, and a composite output determined by a detected output, such method comprising the steps of:
- storing during a first phase, an input value of a reference digital to analog converter as a calibrated output value of a first analog to digital converter of the composite analog to digital converter and corresponding detected output of the first analog to digital converter in a calibration table;
- and storing, during a second phase, an input value of the reference digital to analog converter as a calibrated output value of a second analog to digital converter of the composite analog to digital converter and corresponding detected output of the second analog to digital converter in the calibration table.
A self-calibrating analog to digital converter comprising:
- means for generating a calibration table relating a calibrated output of the analog to digital converter and a detected output;
- means for interconnecting an output of a reference digital to analog converter to an input to the analog to digital converter;
- means for incrementally applying an input to the reference digital to analog converter from a minimum input value to a maximum input value;
- storing an average input value of the reference digital to analog converter, measured between changes in the detected output, as a calibrated output value of the analog to digital converter and corresponding detected output of the analog to digital converter in the calibration table;
- and look-up means for, in response to an external analog signal input to the analog to digital converter being converted to a signal approximately equal to the stored detected output, providing, by reference to the calibration table, the stored calibrated output corresponding to the detected output as a calibrated digital output representation of the external analog signal.
A self-calibrating composite analog to digital converter comprising:
- a plurality of analog to digital converters, equal to a composite number, and including a first and second analog to digital converter, all operatively coupled together for outputting a composite output signal;
- a reference digital to analog converter operatively coupled to an input of the plurality of analog to digital converters for converting first and second input values into first and second analog signals, respectively, for input to the first and second analog to digital converters, respectively;
- a reference signal generator operable for generating known input values including the first and second input values;
- a memory operatively coupled to the plurality of analog to digital converters and the reference signal generator for storing during a first phase the first input value generated by the reference signal generator as a calibrated output value of the first analog to digital converter and a corresponding detected output of the first analog to digital converter in a calibration table, and for storing, during a second phase, the second input value as a calibrated output value of the second analog to digital converter and a corresponding detected output of the second analog to digital converter in the calibration table.
Dependencies are inferred from the claim text.