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:
Oct. 14, 1997
Filed:
Mar. 08, 1996
Thomas Singkiat Liong, San Jose, CA (US);
Krishnakumar Rao, Fremont, CA (US);
Parveen Kumar Gupta, Fremont, CA (US);
Mylex Corporation, Fremont, CA (US);
Abstract
A method and apparatus providing a battery backup for a dynamic random access memory (DRAM) cache system that senses the V.sub.cc level supplied through the cache controller to the cache memory and, if V.sub.cc falls below a preset threshold level, the battery backup apparatus switches the cache memory array to a backup battery V.sub.cc source, and a backup refresh control generator unit that is also powered by the backup battery V.sub.cc source. The cache DRAM, backup battery, and backup refresh generator are physically contained in a single module that can be disconnected from the cache controller and host computer system while preserving the cache memory contents. The backup system is installed in an operating host system for recovery of the cache memory contents and/or resumption of execution of the program that was running when the V.sub.cc power failure occurred.