US 12,355,399 B2
Inductive-capacitive voltage-controlled oscillator with increased common-mode impedance
Abhishek Bhat, Allentown, PA (US); and Joseph V. Pampanin, Hellertown, PA (US)
Assigned to Cisco Technology, Inc., San Jose, CA (US)
Filed by Cisco Technology, Inc., San Jose, CA (US)
Filed on Aug. 25, 2023, as Appl. No. 18/456,373.
Prior Publication US 2025/0070715 A1, Feb. 27, 2025
Int. Cl. H03B 5/12 (2006.01); H03L 7/099 (2006.01)
CPC H03B 5/1253 (2013.01) [H03B 5/1212 (2013.01); H03B 5/1215 (2013.01); H03B 5/1228 (2013.01); H03B 5/1243 (2013.01); H03L 7/099 (2013.01); H03B 2200/0062 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A voltage-controlled oscillator (VCO) comprising:
an inductor-capacitor (LC) tank coupled with a first voltage supply node;
a pair of cross-coupled transistors that are coupled with the LC tank and coupled with each other at a tail node; and
a high-frequency current return path to the first voltage supply node, the high-frequency current return path comprising:
a first decoupling capacitor coupled with the first voltage supply node and a second voltage supply node; and
a first inductor coupled with the tail node and the second voltage supply node, wherein the first inductor is formed as a first conductive trace and has a quality factor (Q) value of 25 or greater.