摘要:
A semiconductor memory device has 2.sup.n word lines, a plurality of bit lines, a plurality of nonvolatile memory cells disposed at each intersection of the word lines and the bit lines, a write circuit for writing data to a memory cell located at an intersection of selected ones of the word lines and the bit lines, and a sense amplifier for reading data out of the memory cells. Further, the semiconductor memory device comprises a first unit for simultaneously selecting a block of 2.sup.m (n>m) word lines among the 2.sup.n word lines, and a second unit for not selecting a block of 2.sup.k (m>k) word lines among the 2.sup.m word lines. The second unit does not select the block of 2.sup.k word lines, and selects a block of 2.sup.k word lines prepared outside the 2.sup.n word lines when any one of the 2.sup.k word lines among the 2.sup.m word lines is defective. Consequently, redundant word lines are effectively employed, write and verify operations are stable, and thereby the yield and performance of the semiconductor memory device are improved.
摘要:
According to an aspect of the invention, there is provided an information processing device including: a display unit configured to display a plurality of setting informations of a setting of function indicated by indication information displayed on a standby screen; a key unit configured to accept a selection of one piece of setting information among the plurality of setting informations; a control unit configured to cancel or change function setting, based on the setting information of which the selection is accepted by the key unit; and a display control unit configured to control a display of the indication information, which is performed by the display unit, in accordance with the cancel or the change of function setting performed by the control unit.
摘要:
A nonvolatile memory has a plurality of memory cells, each of the memory cells having a first and a second source/drain areas, a control gate, and an insulating trap layer disposed between the control gate and a channel area lying between the first and the second source/drain areas. The trap layer includes a use bit area in proximity to the first source/drain area, for storing data depending on the presence or absence of electric charge to be trapped, and a non-use bit area in proximity to the second source/drain area, in which the electric charge is trapped while data is held in the use bit area. Preferably, in the state where erasing operation is completed, the non-use bit area is brought into a state where electric charge is trapped therein.
摘要:
A semiconductor memory that prevents a decrease in margin at read time. A bit line in a floating state between a drain in a memory cell to be read and a charged bit line is charged for a certain period of time.
摘要:
A mobile communication terminal is provided with a light-emitting element for notifying an unanswered incoming call. When the cancellation of an incoming call is canceled in a state where an incoming call response operation has not been carried out, the mobile communication terminal is brought into the standby state and then the light-emitting element is caused to emit light.
摘要:
A non-volatile semiconductor storage device provided with a boost circuit for setting, for at least a certain period of time, a source line selectively connected to a memory cell to a negative potential, when reading out data from the memory cell is disclosed.
摘要:
The present invention is a non-volatile memory device, wherein programming or erasing of memory cells is carried out by injecting or removing carriers in floating gates in the memory cells, comprising: a plurality of memory blocks each comprising a plurality of memory cells, respectively; and an erasing circuit for applying an erasing stress in units of the memory blocks and verifying that erasure has been completed in units of memory cells; wherein the erasing circuit applies an erasing stress to the plurality of memory blocks simultaneously until a past erasing stress minimum value for the plurality of memory blocks. According to the aforementioned invention, an erasing stress value, such as a number of erasing stress applications, is recorded for each memory block in past erasing operations, and the minimum erasing stress value of these erasing stress values is recorded. In the next erasing operation, an erasing stress is applied to a plurality of memory blocks in one batch, until this minimum erasing stress value is reached. Therefore, the erasing time can be shortened in comparison with a conventional method where application of erasing stress and erasure verification are repeated for each memory block, after respectively.
摘要:
A flash-erasable semiconductor memory device has a memory cell array including a plurality of memory cell transistors each having an insulated floating gate for storing information and a control electrode provided on the floating gate, wherein the flash-erasable semiconductor memory device includes a write control circuit supplied with a write control signal, when writing information. The write control circuit produces a control signal such that a leading edge of the drain control signal appears after a leading edge of the gate control signal. Further, the gate control circuit shuts off the gate control signal such that a trailing edge of the gate control signal appears after a trailing edge of the drain control signal.
摘要:
A flash-erasable semiconductor memory device comprises a memory cell array including a plurality of memory cell transistors each having an insulated floating gate for storing information and a control electrode provided on said floating gate, wherein the flash-erasable semiconductor memory device includes a write control circuit supplied with a write control signal, when writing information. The write control circuit produces a control signal such that a leading edge of the drain control signal appears after a leading edge of the gate control signal. Further, the gate control circuit shuts off the gate control signal such that a trailing edge of the gate control signal appears after a trailing edge of the drain control signal.
摘要:
A nonvolatile memory device that responds to a decrease in electric charge stored in memory cells attributed to the charge loss phenomenon occurring during program operation by adjusting the level of a program verify operation according to the degree of the charge loss so that the program operation can be performed with little (if any) interruption.