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:
Jan. 03, 2012
Filed:
Oct. 22, 2009
Applicants:
Roderick Mclachlan, Edinburgh, GB;
Samuel Blackburn, Edinburgh, GB;
Inventors:
Roderick McLachlan, Edinburgh, GB;
Samuel Blackburn, Edinburgh, GB;
Assignee:
Analog Devices, Inc., Norwood, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03M 1/10 (2006.01);
U.S. Cl.
CPC ...
Abstract
The invention is a novel scheme of calibrating a voltage-mode digital to analog converter using a current-mode digital to analog converter. A DAC system is comprised of a voltage-mode DAC with an R-2R architecture structure and includes a ROM lookup table where calibration codes associated with each of a plurality of input codes are stored. A reference current is scaled with the calibration codes to output a calibration current that induces adjustments in an output voltage to counteract non-linearities that may be induced by resistor mismatch.