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:
Dec. 20, 1994
Filed:
Dec. 08, 1993
Robert W Berry, Jr, Round Rock, NY (US);
Bernd K Koenemann, Hopewell Junction, NY (US);
William J Scarpero, Jr, Poughkeepsie, NY (US);
Philip G Shephard, III, Wappingers Falls, NY (US);
Kenneth D Wagner, Sunnyvale, CA (US);
Gulsun Yasar, Poughkeepsie, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A memory embedded in a integrated processor chip is dynamically stressed tested by repeatedly writing a test pattern to the data locations of the memory in which a high percentage of the memory cells are sequentially written with complementary data in order to create a high stress on the memory devices. The test pattern is generated as a function of the number of address locations of the memory and the number of data bits of a memory data word. The test pattern is rotated each time the memory is addressed. The test pattern preferably has a contiguous group of digits with the number of digits in the contiguous group being a function of the number of address locations and the number of data bits in the memory word. The memory data input register is configured as a recirculating loop and additional dummy bits are added to provide recirculating loops longer than the data input register. A plurality of independent circulating loops may be created in the data input register or in combination with a number of dummy register bits.