The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 14, 2020
Filed:
Sep. 20, 2017
Applicant:
Qualcomm Incorporated, San Diego, CA (US);
Inventor:
Jingcheng Zhuang, San Diego, CA (US);
Assignee:
QUALCOMM Incorporated, San Diego, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
G01R 23/02 (2006.01); G01R 25/00 (2006.01); H03L 7/089 (2006.01);
U.S. Cl.
CPC ...
G01R 23/02 (2013.01); G01R 25/00 (2013.01); H03L 7/089 (2013.01);
Abstract
A phase frequency detector (PFD) isolates supply (e.g., voltage supply) to a reference path and a feedback path of a phase locked loop (PLL) such that the power supply to the reference path is independent of the power supply to the feedback path. This isolation improves linearity. In one instance, the PFD includes a supply voltage, one or more switches, a reference capacitor and a feedback capacitor. The reference capacitor is selectively coupled to the supply voltage via the one or more switches and the feedback capacitor is selectively coupled to the supply voltage via the one or more switches.