Title :
Design and high-speed testing of a superconducting delta-sigma oversampled converter
Author :
Xiao, P.H. ; Hebert, D. ; Whiteley, S.R. ; Van Duzer, T.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., California Univ., Berkeley, CA, USA
fDate :
6/1/1995 12:00:00 AM
Abstract :
A delta-sigma modulator with a lowpass filter can achieve the same signal-to-noise ratio (SNR) and dynamic range as a delta-sigma modulator with an integrator by adjusting the cut-off frequency of its lowpass filter. A lowpass filter modulator in superconducting niobium technology was designed and tested up to a 1 GHz sampling rate and was shown to be operating correctly. The bits of a pseudo-random bit stream digital output are acquired individually by a high-speed logic analyzer. The acquired data show 6 bits of modulator dynamic range, which is limited below the simulated value of 11 bits, at least in part, by errors in the test equipment.<>
Keywords :
Josephson effect; integrated circuit testing; low-pass filters; sigma-delta modulation; superconducting device testing; superconducting integrated circuits; 1 GHz; delta-sigma converter; high-speed testing; lowpass filter modulator; oversampled converter; pseudo-random bit stream digital output; superconducting ADC; superconducting Nb technology; Cutoff frequency; Delta modulation; Dynamic range; Niobium; Sampling methods; Signal to noise ratio; Superconducting filters; Superconducting logic circuits; Test equipment; Testing;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
