Semiconductor memory device
AssigneeElpida Memory, Inc.
InventorHisashi Abo
Life of this patent
Estimating the term…
Abstract
To prevent data quality from being deteriorated by reflection from each of memory modules, a semiconductor memory device has a switching circuit located on a mother board in the vicinity of a branching point of the data bus. The switching circuit is controlled by a memory controller to selectively operate the memory modules without substantial reflection from a selected one of the memory modules. To this end, each of the memory modules and the memory controller is terminated with characteristic impedance of the data bus.
Claims12
A semiconductor memory device comprising a plurality of memory modules, a memory controller which controls the memory modules, and a bus for interconnecting the memory modules and the memory controller, the semiconductor memory device further comprising:
- a switching circuit which is connected to the bus between the memory controller and the memory modules to selectively put the plurality of the memory modules into a connected state;
- the bus being branched through the switching circuit into the respective memory modules.
A semiconductor memory device comprising a mother board, a plurality of memory modules attachable to the mother board, a memory controller mounted on the mother board to control the memory modules, and a bus which has a board portion wired on the mother board and module portions wired on the memory modules to interconnect the memory modules and the memory controller, the semiconductor memory device further comprising:
- a switching circuit which is located on the mother board to connect the board portion of the bus to the module portions to selectively put the plurality of the memory modules into a selected state without reflection from the memory module of the selected state.
Dependencies are inferred from the claim text.