RSFQ-based D/A converter for AC voltage standard

A Josephson digital-to-analog (D/A) converter for synthesizing a sinusoidal waveform with metrological accuracy has been developed. The D/A converter is made up of rapid single-flux quantum (RSFQ) logic circuits, a frequency multiplier (FM), a pulse distributor (PD) and voltage multipliers (VM). The VM circuit multiplies the number of RSFQ pulses by a factor of 2 to the nth power. A programmable output voltage is obtained when the input SFQ pulses are gated from the FM to the VMs using PD circuits.