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. 17, 2001
Filed:
Mar. 03, 2000
Geordie M. Braceras, Essex Junction, VT (US);
Steven H. Lamphier, St. Albans, VT (US);
Harold Pilo, Underhill, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A SRAM module provides programmability of AC timings such that an end user can adjust or “tweak” the AC timings to maximize system performance. A variable delay circuit is placed in the path between a signal (e.g., data signal or address signal)and the SRAM set-up and hold register which allows the user to shift the setup-and-hold window by selected increments. The delay circuit can either advance or retard the AC timings. A delay program controlling the delay circuit is selected in one of two ways; either by a default AC timing program stored in a ROM device and preset by the manufacturer, or by a private JTAG instruction and AC programming data input by the user through the JTAG state machine provided on the SRAM chip. Once the optimum delay (or advance) is selected to optimize the SRAM to the cache system this user program may be permanently burned into the default ROM such that the optimum timings are used thereafter as the default.