Rapid single flux quantum digital-to-analog converter for ac voltage standard

A digital-to-analog (D/A) converter based on rapid single flux quantum (RSFQ) circuits is a potential device for establishing a new generation of ac voltage standards. We are developing RSFQ D/A converters that can generate an ac waveform with an accurately defined rms value. Our goal in the near future is the synthesis of an ac waveform with a 100-mV peak voltage that will allow accurate characterization of the thermal voltage converters currently used for setting ac-dc transfer standards. We have designed, fabricated and successfully tested key subsystems of the RSFQ D/A converter including a 10-stage pulse-number multiplier, a 1-bit slice of a pulse distributor and a 9.5-bit voltage multiplier