Pii: S0964-1807(99)00018-6
نویسندگان
چکیده
ÐResidue number system (RNS) arithmetic has a promising role for fault-tolerant high throughput superconducting single ̄ux quantum (SFQ) circuits for digital signal processing (DSP) applications. We have designed one of the basic computational blocks used in DSP circuits, one-decimaldigit RNS adder. A new design for its main component, the single-modulus adder, has been developed. It combines simple and robust RSFQ elementary cells, both combinational and sequential. The central units are a circular shift register, a code converter, and the clock control circuitry. Our mod5 adder employs 195 Josephson junctions, consumes 50 mW of power, and occupies an area of less than 2 mm. Chips were fabricated at HYPRES, Inc. using 1 kA/cm low-Tc Niobium technology. The mod5 adder was successfully tested at low speed, and gave experimental bias margins of 226%. # 1999 Published by Elsevier Science Ltd. All rights reserved
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