Two-Level Switches for Advanced Time-Division Multiplexing

• Published in: IEEE transactions on applied superconductivity 2019-08, Vol.29 (5), p.1-5
• Main Authors: Dawson, Carl S., Chaudhuri, Saptarshi, Titus, Charles J., Hsiao-Mei Cho, Denison, Edward V., Doriese, W. Bertrand, Durkin, Malcolm, FitzGerald, Connor T., Hilton, Gene C., Irwin, Kent D., Li, Dale, O'Neil, Galen C., Reintsema, Carl D., Steffen, Zach, Stevens, Robert W., Swetz, Daniel S., Ullom, Joel N., Vale, Leila R., Weber, Joel C., Young, Betty A.
• Format: Article
• Language: English
• Subjects: CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Current measurement; Ethernet; Multiplexing; Pixels; Resistance; Sensor arrays; SQUIDs; Subgroups; superconducting electronics; Superconducting quantum interference devices; Switches; Time division multiplexing; transition-edge sensors; Wires; Wiring
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2019.2903394

Superconducting quantum interference device (SQUID)-based time-division multiplexing (TDM) is a mature and widely implemented technology used to read out transition-edge sensor arrays. As the number of pixels in modern arrays continues to increase, a higher multiplexing factor is required to reduce the number of wires and amplifier channels. However, as the multiplexing factor is increased, the number of row-select wires (used to turn on a row of TDM SQUIDs in a two-dimensional configuration) also increases, limiting the reduction in array wires. We present a more advanced TDM architecture that implements multi-level switching between subgroups of pixels. We show that this technique can dramatically reduce the number of required row-select lines. We also present the design, fabrication, and testing of a TDM multiplexer incorporating a two-level switch, which implements a second switch for each group of ten TDM pixels. In this implementation, a multiplexing factor of 100 can be addressed using ten group-select wiring pairs and ten row-select wiring pairs. We demonstrate multiplexer functionality and present measured operating margins of this new TDM multiplexer.