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:
May. 27, 2008
Filed:
Apr. 25, 2002
Chun Ying Chen, Irvine, CA (US);
Chun Ying Chen, Irvine, CA (US);
Broadcom Corporation, Irvine, CA (US);
Abstract
A phase rotator generates an output signal having plurality of possible output phases with reduced phase jitter. The low jitter phase rotator includes a plurality of differential amplifiers configured to receive a plurality of input differential signals having different phases, and configured to generate a plurality of weighted signals responsive to the plurality of input differential signals. A plurality of digital-to-analog converters (DAC) are arranged into a plurality of groups, each group of DACs configured to provide current for one of the corresponding differential amplifiers. The number of active DACs in each group of DACs determines a relative weighting of the weighted signals, where relative weighting determining an output phase of an output signal of the phase rotator. The DACs are configured to adjust the output phase of the phase rotator. At a kphase, N/4 adjacent DACs are activated that are indexed as m, m, . . . m, wherein N is the number of said plurality of DACs. At (k+1)phase, a mDAC is activated that is adjacent to the mDAC. At (k+2)phase, the mDAC is de-activated.