Title :
Evaluation of dynamic range for an HTS sigma-delta modulator with 100-GHz sampling
Author :
Saitoh, K. ; Soutome, Y. ; Fukazawa, T. ; Furuta, F. ; Takagi, K.
Author_Institution :
Adv. Res. Lab., Hitachi Ltd., Tokyo, Japan
fDate :
6/1/2003 12:00:00 AM
Abstract :
Circuit simulations were used to study the capability of a high-temperature superconducting (HTS) sigma-delta modulator using interface-engineered-Josephson junctions (IEJ\´s). The dynamic range was calculated while varying the temperature (T) and input-signal frequency (f0), and in the resultant power spectra, correct noise shaping (6 dB/oct) was found. Investigation of the dynamic range in terms of effective number of bits (ENOB) showed that ENOB was 6.7 for f0<200 MHz and T<40 K. At higher input-signal frequencies, i.e., 400 MHz0<1 GHz, ENOB was determined to be in the range 3.240 K.
Keywords :
Josephson effect; high-speed integrated circuits; modulators; sigma-delta modulation; signal sampling; superconducting integrated circuits; 100 GHz; 4.2 to 77 K; HTS sigma-delta modulator; Josephson transmission line; LR integrator; RSFQ circuits; balanced comparator; circuit simulation; dynamic range evaluation; high-temperature superconducting modulator; interface-engineered-Josephson junctions; noise shaping; rapid single flux quantum circuits; Circuit simulation; Delta-sigma modulation; Dynamic range; Frequency estimation; High temperature superconductors; Josephson junctions; Sampling methods; Superconducting device noise; Temperature dependence; Temperature distribution;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2003.813886
