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:
Jun. 28, 2011
Filed:
Feb. 04, 2010
Jun-bae Kim, Seoul, KR;
Yang-ki Kim, Seoul, KR;
Jun-bae Kim, Seoul, KR;
Yang-ki Kim, Seoul, KR;
Samsung Electronics Co., Ltd., Gyeonggi-do, KR;
Abstract
Provided is a semiconductor device for performing a calibration operation without an external ZQ calibration command and a calibration method thereof. The semiconductor device includes a calibration circuit for performing a pull-down calibration operation in response to a pull-down calibration enable signal and a command control unit for generating the pull-down calibration enable signal in response to a DLL reset signal. The calibration method includes adjusting an impedance of a first pull-up resistance structure in response to pull-up calibration codes having a default value. A pull-down calibration enable signal may be generated in response to a DLL reset signal. A voltage of the first node and a reference voltage are compared by a comparator. The comparator outputs pull-down calibration codes based on the comparison. An impedance of a pull-down resistance structure is adjusted, so a resistance of the pull-down resistance structure is equal to a resistance of the first pull-up resistance structure.