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:
Dec. 03, 2002
Filed:
Aug. 08, 2001
Yvette P. Lee, Austin, TX (US);
Marwan M. Hassoun, Austin, TX (US);
Xilinx, Inc., San Jose, CA (US);
Abstract
A segmented digital-to-analog converter (DAC) has been described that uses a two-step calibration process to calibrate current sources to a single primary reference source. In one embodiment, the DAC includes sub-DACs, a reference generator circuit and a primary, or golden, reference source. Current sources of both the sub-DACs and the reference generator are calibrated to a golden current source or primary reference current. In one embodiment, the current sources each include a transistor coupled so that a gate voltage can be adjusted during calibration. The multiple current sources of the reference generator are first calibrated to the primary reference source. The calibrated output currents of the reference generator are then used to calibrate current sources in the sub-DACs.