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:
Feb. 04, 2014
Filed:
Oct. 22, 2012
Applicant:
Micrel, Inc., San Jose, CA (US);
Inventor:
Dashun Xue, Austin, TX (US);
Assignee:
Micrel, Inc., San Jose, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03L 7/06 (2006.01);
U.S. Cl.
CPC ...
Abstract
A filter circuit in a phase-locked loop circuit includes a capacitor coupled between a control voltage node and a first node; and a variable resistive element coupled between the first node and a ground potential. The variable resistive element has a resistance value modulated by a current proportional to the charge pump current of the charge pump. In one embodiment, the variable resistive element is a MOS transistor biased in the linear region and having a drain-to-source resistance modulated by the current proportional to the charge pump current.