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:
Jul. 16, 2013
Filed:
Mar. 30, 2012
Dashun Xue, Austin, TX (US);
Dashun Xue, Austin, TX (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A phase locked loop including first and second charge pumps, a voltage buffer and a bias generator for adaptive biasing for improved performance. A voltage controlled oscillator, feedback circuit and phase detector portions may be provided to operate similar to conventional configurations. The first charge pump receives an adjust signal, such as from the phase detector, and selectively charges an intermediate node. The second charge pump receives the adjust signal and selectively charges a control node developing the control voltage for the VCO. A loop filter capacitor is referenced to the intermediate node. The voltage buffer, replacing the loop filter resistor, buffers the intermediate node and drives the control node. The bias generator converts the control voltage to a converter bias current based on the control voltage and adjusts the charge pump currents and a bias current of the voltage buffer.