MEMORY CELL FOR SUPERCONDUCTING CIRCUIT AND CIRCUIT USING THE SAME

摘要

PROBLEM TO BE SOLVED: To enable coincident selection of two lines even at an RSFQ circuit. SOLUTION: A latch circuit 12 is set which latches a one magnetic flux quantum pulse Qx for (x) selection and outputs a latch output Q×L. When receiving the latch output Q×L, or a one magnetic flux quantum pulse Qy for (y) selection in addition to the latch output, an equivalent inductance- switching circuit 11 provided switches an equivalent inductance to be inserted in series to a signal propagation route of the one magnetic flux quantum pulse Qy from a first value L0 to a larger second value L0 <+> . When detecting the one magnetic flux quantum pulse Qy while receiving a d.c. bias current Ib, a non-latch type Josephson junction J0 provided at an output stage has a critical current of a size whereby the junction changes to a voltage state if the equivalent inductance of the first value L0 is interposed in series in the signal propagation route and stays at a zero voltage state when the equivalent inductance of the second value L0 <+> is interposed. Moreover, a superconducting closed loop is set to catch the one magnetic flux quantum pulse Qy including the equivalent inductance of the second size L0 <+> when the Josephson junction J0 remains in the zero voltage state.