Stable 1 volt programmable voltage standard

Several fully functional programmable voltage standard chips, each having a total of 32 768 Nb–PdAu–Nb Josephson junctions, have been fabricated and tested. The chips are based on a new design that provides fast programmability (1 μs) between voltages and stable voltage operation from $\text{−1}$ to $\text{+1\hspace{0.17em}}\mathrm{V}.$ A comparison of the new standard with a conventional Josephson voltage standard is in agreement to $\text{0.5±1.1}$ parts in ${10}^9.$ We demonstrate the utility of this standard by measuring the linearity of a digital voltmeter.