A analogue-digital converter using josephson dac and method thereof

An analog-digital converter using a Josephson DAC(Digital Analog Converter) and a method thereof are provided to execute the Josephson ADC(Analog Digital Converter) accurately by combining a programmable array with a prior ADC. An input stage ADC(Analog Digital Converter)(10) converts an analog input signal into digital data. A Josephson DAC(Digital Analog Converter)(20) converts the digital data from the input stage ADC into analog data. A differential ADC(30) extracts a difference voltage between a reference output voltage of the Josephson DAC and an unknown input signal. A data processor(40) adds output data of the differential ADC and output data of the input stage ADC.