Article

High resolution ADC system

HYPRES Inc., Elmsfrd, NY
IEEE Transactions on Applied Superconductivity (Impact Factor: 1.2). 07/1997; DOI: 10.1109/77.621783
Source: IEEE Xplore

ABSTRACT We have developed and verified experimentally a novel
high-resolution superconducting ADC architecture based on phase
modulation/demodulation principle and implemented in RSFQ logic. We have
demonstrated an ADC chip providing full implementation of this
architecture, including on-chip decimation filter and multiple-channel
synchronizer. We have also developed a digital ADC evaluation system
consisting of an interface electronics block converting the low-voltage
ADC output to standard TTL form at multi-MHz sampling rate, and a
computerized test station performing data acquisition, processing and
display in real time. Using this system we have demonstrated that for
low-frequency (kHz) signals our ADC chips possess linearity in excess of
16 bits with Spur-Free Dynamic Range over 108 dB, which is an important
benchmark for any high-resolution ADC technology

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