Oracle International Corporation

Sun Microsystems, Inc.

Neil Duncan

Clement Fang

David Jeffrey

Gregory Frederick Grohoski

Heechoul Park

Tayung Wong

Lik Cheng

Kenneth J Gibbons

Embodiments of a row address cache circuit are disclosed that may allow the determination the number of times a row address is used to access a dynamic memory. The row address cache circuit may include a memory, first and second pluralities of counters, and a control circuit. The control circuit may be configured to receive a row address and store the row address in an entry of the memory when the row address has not been previously stored. When the row address has been previously stored in an entry of the memory, the control circuit may be configured to change a value of a counter of the first plurality of counters corresponding the entry. The control circuit may be further configured to change a value of each counter of the second plurality of counters after a pre-determined time interval has elapsed, and initiate a refresh of the dynamic memory.

Detection of multiple accesses to a row address of a dynamic memory within a refresh period

A system and method for storing error correction check words in computer memory modules. Check bits stored within a given word line in a dynamic random access memory (DRAM) chip are assigned to different check words. By assigning check bits to check words in this manner, multi-bit soft errors resulting from the failure of a word line will appear as single-bit errors to an error correction subsystem.

Method for improving un-correctable errors in a computer system

A memory module for use in a two rank memory module system includes a plurality of memory devices and a control circuit. In one embodiment, the control circuit may be configured to generate a chip select signal that is provided to each of the memory devices. The chip select signal may be dependent upon assertions of a first bank chip select signal and a second bank chip select signal received from a memory controller. The control circuit may be further configured to generate an address signal that is provided to each of the memory devices. The address signal may be asserted dependent upon which of the first bank chip select signal and the second bank chip select signal are asserted.

Single rank memory module for use in a two-rank memory module system

Growing community of inventors

Pleasanton, CA, United States of America

Neil Duncan