Digital and analog measurements of HTS SFQ RS flip-flops and shift register circuits

Author

Kim, Y.H. ; Kang, J.H. ; Sung, G.Y. ; Park, J.H. ; Lee, J.M. ; Jung, K.R. ; Kim, C.H. ; Hahn, T.S. ; Choi, S.S.

Author_Institution

Korea Inst. of Sci. & Technol., Seoul, South Korea

Volume

9

Issue

2

fYear

1999

fDate

6/1/1999 12:00:00 AM

Firstpage

3817

Lastpage

3820

Abstract

We fabricated reset-set (RS) flip-flops and shift registers by using YBCO bicrystal junctions and tested their operations by using a computer-controlled digital measurement set-up and an analog measurement set-up. The RS flip-flop circuits operated successfully at temperatures up to 71 K. The RS flip-flop circuit was observed over 600 computer-generated clock cycles with nearly no errors. The circuits were reset or set during each clock cycle. By using an analog measurement technique, we operated the RS flip-flop circuits at frequencies of up to 500 Hz. Since our probe was not designed for high speed operation, the test speed was limited to this frequency. Although we could not operate the shift register completely, we observed flux propagation in the shift register.

Keywords

barium compounds; flip-flops; high-temperature superconductors; shift registers; superconducting logic circuits; yttrium compounds; 500 Hz; 71 K; HTS SFQ circuit; YBCO bicrystal junction; YBaCuO; analog measurement; computer-controlled digital measurement; flux propagation; reset-set flip-flop; shift register; Analog computers; Circuit testing; Clocks; Computer errors; Flip-flops; Frequency; High temperature superconductors; Measurement techniques; Shift registers; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.783859

Filename

783859