US 11,942,937 B2
Pulse-generator-based bias-level sensors for reciprocal quantum logic
Charles Ryan Wallace, Orlando, FL (US); Max E. Nielsen, Riverton, UT (US); Alexander Louis Braun, Baltimore, MD (US); Daniel George Dosch, Glen Burnie, MD (US); Kurt Pleim, Halethorpe, MD (US); and Haitao O. Dai, Ellicott City, MD (US)
Assigned to NORTHROP GRUMMAN SYSTEMS CORPORATION, Falls Church, VA (US)
Filed by Charles Ryan Wallace, Orlando, FL (US); Max E. Nielsen, Riverton, UT (US); Alexander Louis Braun, Baltimore, MD (US); Daniel George Dosch, Glen Burnie, MD (US); Kurt Pleim, Halethorpe, MD (US); and Haitao O. Dai, Ellicott City, MD (US)
Filed on May 4, 2022, as Appl. No. 17/736,517.
Prior Publication US 2023/0361776 A1, Nov. 9, 2023
Int. Cl. H03K 19/195 (2006.01); H03K 3/38 (2006.01); H03K 19/17736 (2020.01); H03K 19/20 (2006.01)
CPC H03K 19/195 (2013.01) [H03K 3/38 (2013.01); H03K 19/1774 (2013.01); H03K 19/17744 (2013.01); H03K 19/20 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A reciprocal quantum logic (RQL) system comprising:
an RQL integrated circuit (IC) comprising:
operational RQL circuitry configured to perform one or more computational functions, the operational RQL circuitry comprising a first Josephson junction (JJ), the operational RQL circuitry being inductively coupled to a bias signal source to provide biasing to the first JJ; and
bias-level sensing circuitry configured to sense one or more parameters of bias signals provided to the operational RQL circuitry, the bias-level sensing circuitry comprising at least first and second bias-level sensors, each of the first and second bias-level sensors comprising a respective pulse generator comprising a second JJ coupled to the bias signal source, the pulse generator having an output configured to provide a reciprocal pair of single flux quantum (SFQ) pulses with each AC cycle of an AC signal provided by the bias signal source based on the amplitude of the AC signal being within operating margins of the pulse generator.