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:
Jul. 09, 2013
Filed:
Sep. 23, 2010
Eer-wen Tyan, Hsinchu Hsien, TW;
Ming-chieh Yeh, Hsinchu Hsien, TW;
Eer-Wen Tyan, Hsinchu Hsien, TW;
Ming-Chieh Yeh, Hsinchu Hsien, TW;
MStar Semiconductor, Inc., Hsinchu Hsien, TW;
Abstract
An I/O calibration method and an apparatus are provided for calibrating a driving impedance at an output end of an I/O circuit in a chip. The chip further includes a plurality of basic impedances and a non-volatile memory. The I/O circuit calibration method includes: measuring an impedance value of one basic impedance and recording the measured impedance value in the non-volatile memory; synthesizing a calibration impedance by selectively conducting the basic impedance(s); adjusting the number of the conducted basic impedance(s) in the calibration impedance and estimating an impedance value of the driving impedance according to the measured result and a voltage divided by the calibration impedance and the driving impedance at the output end.