Back to results
US 6,636,454 B2Granted
Low-power consumption semiconductor memory device
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorsTakeshi Fujino, Kazutami Arimoto, Hiroki Shimano
Life of this patent
Estimating the term…
Abstract
A memory cell unit includes a first storage element and a second storage element for storing complementary data with each other. In a selected state, the first and second storage elements are connected to complementary bit lines, respectively at a time. In a standby state, the bit lines are precharged to a voltage (Vccs or GND) corresponding to the data stored in the memory cell unit. Refresh-free, low-current-consumption semiconductor memory device operating stably even under a low power supply voltage can be implemented.
Claims8
A semiconductor memory device, comprising:
- a plurality of unit cells arranged in rows and columns, each of said plurality of unit cells having first and second storage elements, each of said first and second storage elements including a capacitor for storing information and an access transistor;
- a plurality of bit line pairs provided corresponding to the respective columns, each of the bit line pairs connecting to the unit cells on a corresponding column, each of the bit line pairs including first and second bit lines respectively coupled to said first and second storage elements of the unit cells of the corresponding column;
- a plurality of row selection lines provided corresponding to the respective rows, each of the row selection lines connecting to the unit cells of a corresponding, each of the row selection lines including a first word line connecting to the first storage elements of the unit cells on a corresponding row, and a second word line connecting to the second storage elements of the unit cells on the corresponding row;
- a row selection circuit for simultaneously driving the first and second word lines of a row selection line arranged corresponding to an addressed row into a selected state according to an address signal;
- and
- a bit-line voltage setting circuit for setting voltages on the first and second bit lines of each of said bit line pairs to a voltage level different from an intermediate voltage level in a standby state, the intermediate voltage level being equal to half a sum of voltages respectively corresponding to high-level and low-level data stored in said first and second storage elements.
3 more elements
Dependencies are inferred from the claim text.