ALEXANDRIA, Va., Feb. 12 -- United States Patent no. 12,224,746, issued on Feb. 11, was assigned to CHANGXIN MEMORY TECHNOLOGIES INC. (Hefei, China).
"Impedance calibration circuit" was invented by Yanian Shao (Hefei, China) and Zhiqiang Zhang (Hefei, China).
According to the abstract* released by the U.S. Patent & Trademark Office: "An impedance calibration circuit including: a calibration circuit configured to receive a first calibration clock signal, to perform impedance calibration on a basis of the first calibration clock signal, and to output a first stop signal when the calibration is completed; a first detection circuit configured to detect calibration time of the impedance calibration circuit, and to output a second stop signal w...