摘要:
The time required for the program verify and erase verify operations can be shortened. The change of threshold values of memory cells can be suppressed even if the write and erase operations are executed repetitively. After the program and erase operations, whether the operations were properly executed can be judged simultaneously for all bit lines basing upon a change, after the pre-charge, of the potential at each bit line, without changing the column address. In the data rewrite oepration, the rewrite operation is not effected for a memory cell with the data once properly written, by changing the data in the data register.
摘要:
A NAND cell type electrically erasable programmable read-only memory has a memory array section containing NAND cell units. Each NAND cell unit has a series array of floating gate type metal-oxide semiconductor field effect transistors as memory cell transistors. The memory section is associated with a control-gate controller, a data-latch circuit, a sense amplifier section, and a data comparator, which is connected via an output buffer to a verify-termination detector. When a data is once written into a selected memory cell in a data programming mode, a specific basing voltage is applied to the selected cell so that the actual electrical data write condition of the selected memory cell is verified. If the comparator detects that the verified write condition is dissatisfied, data-rewriting operations are repeatedly executed by additionally supplied the selected cell with a suitable voltage which compensates for the dissatisfaction of the verified write condition in the selected memory cell transistor.
摘要:
A NAND EEPROM is disclosed which is capable of variously setting, for each chip, the voltage to be applied to the control gates of memory cells. The semiconductor chip includes a NAND memory cell array and a high-voltage generating circuit for generating data writing internal voltage VPP required when data is written on the memory cell array. Moreover, the semiconductor chip includes a set voltage selection circuit for arbitrarily setting the level of the voltage VPP generated by the high-voltage generating circuit for each chip and a multiplexer for extracting, to the outside of the chip, setting signal LTF which is a signal for enabling the level of the voltage VPP set arbitrarily.
摘要:
A semiconductor storage apparatus and a method of writing data to the semiconductor storage apparatus can restrict the threshold value of the memory cells, to which data has been written or from which data has been erased, to be included in a predetermined range without excessive writing by performing a verifying operation. In the writing operation, writing is performed such that a first determining level is set to a loose level which is the same as the level set for the reading operation or higher than the loose level but lower than a finally required determining level. In accordance with the first determining level, a first writing operation is performed. Then, a second writing operation is performed in accordance with a second determining level. The threshold value of a memory cell having a threshold value between the first determining level, which is the loose level, and the second determining level which is the required determining level (an aimed determining level) is raised to be higher than the second determining level, that is, the writing operation is performed by two steps. When the width of the distribution of the threshold values is reduced, data can reliably be erased from all of the memory cells when data is collectively erased in the erasing operation.
摘要:
A sense amplifier for signal detection for use in an electrically erasable and programmable read-only memory (EEPROM). The sense amplifier includes a first clock signal-synchronized inverter including a first inverter and first switch for switching between activating and deactivating states of the first inverter, the first clock signal-synchronized inverter having a first input connected to a corresponding one of the bit lines and a first output. A second clock signal-synchronized inverter is arranged in parallel with the first clock signal-synchronized inverter and includes a second inverter and a second switch for switching between activating and deactivating states of the second inverter, the second clock signal-synchronized inverter having an input connected to the output of the first clock signal-synchronized inverter and an output connected to the input of the first clock signal-synchronized inverter. The switches in the first and second clock signal-synchronized inverters are activated with a delay so that a potential on the corresponding bit line is reliably sensed and latched at the output of the first clock signal-synchronized inverter.
摘要:
A non-volatile semiconductor memory device includes a flip-flop circuit for holding write data in one of first and second states. A bit line is connected to the flip-flop circuit via a switching element and a transistor charges the bit line. A non-volatile memory cell, connected to the bit line and having a MOS transistor structure, stores data when a threshold thereof is set in one of first and second threshold ranges, wherein at the time of a write mode the threshold of the memory cell is shifted from the first threshold range towards the second threshold range while the flip-flop circuit remains in the first state and the shift of the threshold is not effected while the flip-flop circuit remains in the second state, and at the time of a verify mode following the write mode the bit line is kept at a charge potential by the charging transistor while the threshold remains in the second threshold range. A data setting circuit connects one of first and second signal nodes of the flip-flop circuit to a predetermined potential when the bit line is at the charge potential in the verify mode, thereby setting the flip-flop circuit in the second state irrespective of the state prior to the verify mode.
摘要:
A non-volatile semiconductor memory device including a plurality of bit lines; a plurality of word lines insulatively intersecting the bit lines; a memory cell array including a plurality of memory cells coupled to the bit lines and the word lines, each memory cell including a transistor with a charge storage portion; a plurality of programming circuits coupled to the memory cell array (i) for storing data which define whether or not write voltages are to be applied to respective of the memory cells, (ii) for selectively applying the write voltages to a part of the memory cells, which part is selected according to the data stored in the plurality of programing circuits, (iii) for determining actual written states of the memory cells, and (iv) for selectively modifying the stored data based on a predetermined logical relationship between the determined actual written states of the memory cells and the data stored in the plurality of programming circuits, thereby applying the write voltages only to memory cells which are not sufficiently written to achieve a predetermined written state.
摘要:
Disclosed is a semiconductor integrated circuit device, which comprises a booster circuit for boosting a source voltage, a voltage limiter having one end connected to the output terminal of the booster circuit, for limiting the output voltage of the booster circuit to a given value, and a voltage setting circuit, connected to the other end of the voltage limiter, for arbitrarily adjusting a voltage at the other end of the voltage limiter. This design can keep the output voltage of the booster circuit at a constant level and can set that output voltage to an arbitrary voltage.
摘要:
A semiconductor device comprises a stacked layer memory block and associated peripheral circuits, such as a booster circuit, in stacked layer arrangements. The booster circuit includes plural rectifier cells that are series-connected and plural first capacitors. The plural first capacitors receive a first clock signal on one end, and the other ends thereof are each connected to one end of a different rectifier cell. Each first capacitor is composed of plural first conductive layers that are arrayed with a set pitch perpendicular to the substrate. Either the even numbered or the odd numbered first conductive layers are supplied with the first clock signal. The other of the even numbered or odd numbered first conductive layers are each individually connected to one end of a different rectifier cell.
摘要:
In a nonvolatile semiconductor memory device, a stacked body is formed by alternately stacking dielectric films and conductive films on a silicon substrate and a plurality of through holes extending in the stacking direction are formed in a matrix configuration. A shunt interconnect and a bit interconnect are provided above the stacked body. Conductor pillars are buried inside the through holes arranged in a line immediately below the shunt interconnect out of the plurality of through holes, and semiconductor pillars are buried inside the remaining through holes. The conductive pillars are formed from a metal, or low resistance silicon. Its upper end portion is connected to the shunt interconnect and its lower end portion is connected to a cell source formed in an upper layer portion of the silicon substrate.