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:
Mar. 03, 2026
Filed:
Jun. 21, 2022
Rambus Inc., San Jose, CA (US);
Thomas Vogelsang, Mountain View, CA (US);
Torsten Partsch, San Jose, CA (US);
Brent Steven Haukness, Sunnyvale, CA (US);
John Eric Linstadt, Palo Alto, CA (US);
Rambus Inc., San Jose, CA (US);
Abstract
DRAM cells need to be periodically refreshed to preserve the charge stored in them. The retention time is typically not the same for all DRAM cells but follows a distribution with multiple orders of magnitude difference between the retention time of cells with the highest charge loss and the cells with the lowest charge loss. Different refresh intervals are used for certain wordlines based on the required minimum retention time of the cells on those wordlines. The memory controller does not keep track of refresh addresses. After initialization of the DRAM devices, the memory controller issues a smaller number of refresh commands when compared to refreshing all wordlines at the same refresh interval.