PURPOSE: To output unipolar pulse with an AC power source, by installing a unipolar driving circuit which outputs unipolar driving pulse to the output circuit of each address to a decoder circuit using a Josephson junction device which is driven by an AC power source.

CONSTITUTION: A decoder circuit 101 is of a unipolar driving type and the electric power is supplied from an AC power source 102. Address signals A and B are inputted into the decoder circuit 101 from address control lines 111 and 112 and drive output lines 113W116 and the control line of gate circuits 117W120 of a unipolar driving circuit. The gate circuits 117W120 of the unipolar driving circuit drive address output circuits 121W124 by adding a gate driving line 125 from a DC power source 103. In this way, an AC driven Josephson junction decoder circuit which uses a unipolar driving decoder circuit, driven by a DC power source, and can output a unipolar driving pulse is obtained.