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:
Apr. 19, 2011
Filed:
Jun. 04, 2009
Anjali R Malladi, Essex Junction, VT (US);
Pradeep Thiagarajan, Essex Junction, VT (US);
Anjali R Malladi, Essex Junction, VT (US);
Pradeep Thiagarajan, Essex Junction, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Circuits and methods for automated real-time tuning of wide range frequency/delay voltage controlled oscillators (VCO) using a reset mechanism, to account for run-time variations such as power supply, temperature, reference clock frequency and input slew drift etc is described. It finds extensive applications in wide range, multi frequency band phase and delay locked loops. In one embodiment, an automated Jump-Down band switching structure and method for use in VCOs with a plurality of frequency bands is described. This involves monitoring the VCO's analog control voltage signal until it reaches a predetermined lower limit, at which time band switching to an overlapping lower frequency band is triggered by an internally generated reset signal, while simultaneously charging the analog control voltage to a limit in a pre-determined range of the lower band, to avoid phase detector malfunctions in the PLL/DLL system at lower control voltages during band switch.