A/D converter calibration
AssigneeInfineon Technologies AG
InventorChrister Jansson
Life of this patent
Estimating the term…
Abstract
A D/A converter range calibration system in an A/D converter structure including a set of comparators with associated calibrating D/A converters includes means (RCC) for determining the offset error range for the entire set of comparators and means (R-DAC) for adjusting the dynamic range of each calibrating D/A converter to this offset error range.
Claims16
A method of improving accuracy of an A/D converter structure including a set of comparators with associated calibrating D/A converters for providing individual offset voltages and a range D/A converter for providing a common gain control voltage, comprising the steps of:
- providing each comparator with a predefined reference voltage;
- providing each calibrating D/A converter with a common calibration value;
- determining a minimum calibration range value for said range D/A converter to cover a gain control common to all comparators;
- and
- adjusting the individual offset of each comparator by adjusting the associated calibrating D/A converter.
A D/A converter range calibration system in an A/D converter structure, comprising:
- a plurality of comparators each comprising a calibration input coupled with an associated calibrating D/A converter;
- a plurality of calibration registers each coupled with an associated calibrating D/A converter;
- a range D/A converter coupled with said associated calibrating D/A converters;
- a range register coupled with said range D/A converter;
- control means for determining a range gain control value to be stored in said range register for the entire set of comparators.
A D/A converter range calibration system in an A/D converter structure comprising:
- a set of comparators with associated calibrating D/A converters,
- a control unit for determining an gain control value common to the entire set of comparators;
- and
- a range D/A converter for adjusting each calibrating D/A converter by the determined gain control value.
A method of improving accuracy of an A/D converter structure including a set of comparators with associated differential calibrating D/A converters for providing individual differential offset voltages and a differential range D/A converter for providing a common differential gain control voltage, comprising the steps of:
- providing each comparator with a predefined reference voltage;
- providing each calibrating D/A converter with a first calibration value;
- determining a first calibration range value for said range D/A converter to cover a first gain control common to all comparators;
- providing each calibrating D/A converter with a second calibration value;
- determining a second calibration range value for said range D/A converter to cover a second gain control common to all comparators;
- and
- adjusting the individual offset of each comparator by adjusting the differential associated calibrating D/A converter.
Dependencies are inferred from the claim text.