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:
Mar. 01, 2016
Filed:
May. 27, 2011
Siraj Akhtar, Richardson, TX (US);
Richard Francis Taylor, Campbell, CA (US);
Petteri Litmanen, Richardson, TX (US);
Siraj Akhtar, Richardson, TX (US);
Richard Francis Taylor, Campbell, CA (US);
Petteri Litmanen, Richardson, TX (US);
TEXAS INSTRUMENTS INCORPORATED, Dallas, TX (US);
Abstract
A magnetically-coupled structure is integrated with an integrated circuit in back end-of-line (BEOL) digital CMOS fabrication processes. A differential primary (or secondary) coil is formed by patterning a thick copper (Cu) metal layer, and a single-ended secondary (or primary) coil is formed by patterning a thick aluminum (Al) top metal bonding layer. Crossovers and/or cross-unders are formed using thin metal layers. One embodiment provides a stacked balun with a differential primary input winding defined in the copper layer, directly underneath a single-ended spiral winding defined in the aluminum layer. The spiral forms the single-ended secondary output of the balun and is rotated by 90° to prevent metal shorting for its cross-under connections. Another embodiment provides a transformer with one differential primary (or secondary) coil defined in the copper layer and another differential secondary (or primary) coil defined in the aluminum layer and adding a center tap. The position of the tap is selected to compensate for phase differences and provide desired balance.