Back to results
US 2003/0117843 A1Published application
Non-volatile multi-level semiconductor flash memory device and method of driving same
AssigneeHitachi, Ltd.
InventorsNaoki Yamada, Hiroshi Sato, Tetsuya Tsujikawa, Kazuyuki Miyazawa
Life of this patent
Estimating the term…
Abstract
In a nonvolatile semiconductor memory device in which a plurality of threshold values are set to store multi-level data in a memory cell, bits of multi-bit data are separately written into a memory cell according to an address signal or a control signal to effect the reading and erasing. Concretely, the memory array is so constituted that it can be accessed by three-dimensional address of X, Y and Z, and multi-bit data in the memory cell is discriminated by the Z-address.
Claims8
A nonvolatile memory comprising:
- a plurality of word lines;
- a plurality of memory cells;
- and
- a control circuit,
- wherein each of said word lines connects to corresponding ones of said memory cells,
- wherein each of said memory cells is capable of storing multi-bit data including a first bit data and a second bit data,
- wherein said control circuit controls a read operation corresponding to a read command with an address received from outside of the nonvolatile memory,
- wherein said control circuit controls to select one of said word lines and to read said first bit data from said memory cells connected to said selected word line, when receiving said read command with a first type address, and
- wherein said control circuit controls to select said selected word line and to read said second bit data from said memory cells, when receiving said read command with a second type address.
6 more elements
Dependencies are inferred from the claim text.