Patent Number: 8,717,805

Title: Nonvolatile RAM

Abstract: A semiconductor random access memory device includes a memory cell including a resistor whose resistance varies by formation and disappearance of a filament due to an oxidation-reduction reaction of metal ions, a memory area configured to include a first memory area operable in a nonvolatile mode in which a stored content thereof is not lost by a power-off event, and a second memory area operable in a volatile mode in which the stored content thereof is lost by the power-off event, each of the first memory area and the second memory area including the plurality of the memory cells, a register circuit that stores information including a first address information indicating the first memory area, and a second address information indicating the second memory area, and a control circuit that controls the nonvolatile mode, and the volatile mode, with reference to the information stored in the register circuit.

Inventors: Kajigaya; Kazuhiko (Tokyo, JP)

Assignee: Elpida Memory, Inc.

International Classification: G11C 11/00 (20060101)

Expiration Date: 5/06/12018