摘要:
A nonvolatile semiconductor memory device comprising a matrix array of memory cells, word lines for driving the rows of memory cells, bit lines for reading data from columns of memory cells, a plurality of first MOS transistors provided for these bit lines, respectively, a second MOS transistor having a source coupled to the bit lines by the first MOS transistors, a drain coupled to a VCC terminal, and a gate connected to receive a predetermined bias voltage, a row decoder for selecting one of the word lines in accordance with a row-address signal, and a column decoder for turning on one of the first MOS transistors in accordance with a column-address signal. The memory device further has a CE terminal for receiving a test-mode signal, an OE terminal for receiving first and second control signals, and a control circuit for detecting a test mode, thereby prohibiting the operation of the row decoder in response to the first control signal, and permitting the operation of the row decoder in response to the second control signal.
摘要:
This invention provides a non-volatile semiconductor memory having a first node and a second node, the second node having a ground potential. The invention includes a plurality of non-volatile memory cells each having a drain and a threshold potential, the cells, for storing data written into the cells at a predetermined normal writing voltage. A plurality of bit lines, each memory cell being connected to one of the bit lines, transfer data to and from the memory cells. A circuit connected to the bit lines simultaneously tests the memory cells of all the bit lines at the normal writing voltage to detect changes in the threshold potential.
摘要:
Each memory cell in an EPROM includes two memory cell transistors which share a common floating gate and have two separated drains, one of which is connected to a read bit line and the other of which is connected to write bit line. In this EPROM, the read memory cell transistor of the read bit line has a lower hot electron injection rate than the hot electron injection rate of the write memory cell transistor of the write bit line. A bit line voltage booster is connected to the read bit line.
摘要:
A nonvolatile semiconductor memory of this invention is constituted to latch input data into data latch circuits and at the same time control the programming operation of the bit line load transistors when the chip enable signal is made active and a page programming power source voltage is set at the programming voltage, while the output enable signal is kept inactive. Further, when the output enable signal is made active or the programming power source voltage is set at a voltage different from the programming voltage, the data latch circuits are reset. The data latch circuits can be selectively specified by a preset combination of bits.
摘要:
A nonvolatile semiconductor memory of this invention is obtained by dividing a memory cell array in which EPROM cells are provided in a matrix form and a write circuit into a plurality of blocks, commonly connecting sources of cell transistors in each block of the memory cell array, and connecting the common source of each block to a ground node through a corresponding resistive component.
摘要:
A differential amplifier having input terminals connected to first and second nodes lying between the main nonvolatile memory cell section and the nonvolatile dummy cell circuit is used as a sense amplifier. The first and second nodes are pre-charged to a high potential level prior to the data readout operation. The memory cell section and the dummy cell circuit are set in the capacitively balanced condition, thereby making it possible to correctly read out data at a high speed.
摘要:
A semiconductor memory device includes a main memory cell array, a redundancy memory cell array, bonding pads for receiving an address signal, a row decoder for selecting a row of the main memory cell array in accordance with the row address signal, and an exchange controller connected to receive the address signal, which is programmable to inhibit the selective operation of the row decoder to select the row of the redundancy memory cell array, in response to specific address signals. The semiconductor memory device further includes bonding pads, each for receiving a test signal. The exchange controller is connected to receive the test signal for inhibiting the selective operation of the row decoder and selecting the row of the redundancy memory cell array, in response to the test signal.
摘要:
Disclosed is a nonvolatile semiconductor memory having a high access speed and high reliability. The memory includes a source diffusion region extending in one direction, a pair of first word lines arranged in parallel with the source diffusion region, such that the source diffusion region is interposed therebetween, drain diffusion regions disposed to face the source diffusion region, with the first word lines interposed therebetween, bit lines electrically connected to the drain diffusion regions and arranged to cross the first word lines, a channel region formed below each of the first word lines and positioned between the source diffusion region and the drain diffusion region, a floating gate electrode formed in an electrically floating manner above the channel region and below one of the pair of the first word lines, and a second word line formed above the source region and positioned between and electrically connected to the pair of first word lines.
摘要:
There is disclosed a semiconductor memory device comprising a memory cell connected to a bit line, and a clamp circuit comprising a load MOS transistor connected between a power source voltage and the bit line, for clamping the power source voltage and applying the clamped voltage to the bit line. The semiconductor memory device further comprises a bypass circuit connected between the bit line and a reference voltage, for bypassing from the bit line to the reference voltage an electric current the amount of which is substantially equal to that of a weak inversion current of the load MOS transistor flowing into said bit line.
摘要:
A semiconductor memory device in which the differential amplifier circuit compares a potential of a bit line to which memory cells storing information are connected with a reference potential of a dummy line to which a dummy cell is connected, and detects information stored in each of the memory cells. The semiconductor memory device comprises a circuit which discharges both the bit line and the dummy line to a low potential when the chip enable inverted signal is supplied. When the chip enable signal is supplied, therefore, the differential amplifier circuit can detect a difference between the bit line potential and the dummy line potential before the bit line is fully charged up. This makes it possible to produce the chip enable access time and to realize higher speed operations.