High-Speed, High-Accuracy, Self-Calibrating GaAs Mesfet Voltage Coiiparator for A/D Converters

The first GaAs MESFET comparators with internal self calibration circuits are reported. Initial test circuits demonstrated the operation of this self-calibration technique and feasibility of comparator resolutions suitable for correcting most errors in all major subcircuits (including comparators) in 6-10 bit ADC chip ICs at conversion rates up to 2 GHz. Comparator resolutions of one to 5 mV at 1 GHz and yield of about 60% are observed in initial testing.