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:
Apr. 08, 2014
Filed:
Oct. 19, 2011
Chung-shan Kuo, Shulin, TW;
Chung-Shan Kuo, Shulin, TW;
Seoul National University Industry Foundation, Seoul, KR;
Abstract
A method of trimming a reference cell in a semiconductor memory device comprises the steps of: generating a reference current based on a bias voltage applied to the reference cell; generating a first current and a second current based on the value of a control voltage and the resistance of a precision resistor disposed outside the semiconductor memory device; comparing the reference current with the first current; comparing the reference current with the second current; programming the reference cell if the value of the reference current is greater than that of the first current; and erasing the reference cell if the value of the reference current is less than that of the second current. The value of the second current is less than that of the first current.