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:
Nov. 13, 2001
Filed:
Oct. 23, 1998
Hon-Shing Lau, Hsinchu, TW;
Yaw T. Oh, Hsinchu, TW;
Vanguard International Semiconductor Corporation, Hsin-Chu, TW;
Abstract
This invention describes a method to test both auto-refresh and self refresh of an SDRAM. The method writes a logical zero in to a single cell on each word line using a write with auto-precharge and increments an internal counter with either auto-refresh or self refresh to select the row address. The test is performed using existing circuitry on the SDRAM, and when testing self refresh, the refresh cycle is exited shortly after a cell on a row has been written into so as to not run the entire refresh cycle and save test time. A test signature is formed by the logical zeros written into one cell along each word line. Comparing this signature with the signature that should exist provides an easy way to determine if there is a test error and where the error occurred.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile