Abstract: In a semiconductor memory device enabling to lower the source voltage, bit lines (BL) of a memory cell array (11) are selected by a column gate (12) and connected to sense amplifiers (13). Each sense amplifier (13) includes an operational amplifier (OP) having a sense node (SA) as one of its input terminals and a reference node (RE)to be shared with other sense amplifiers (13) as its other input terminal, an NMOS transistor (QN01) as a current source load interposed between the sense node (SA) and a power source (VCC) for each operational amplifier (OP), an NMOS transistor (QN02) as a current source load interposed between the reference node (REF) and the power source (VCC) for each operational amplifier (OP), and a reference voltage generating circuit (21) connected to the reference node (REF) and shared with other sense amplifiers (13) to generate a reference voltage of an intermediate level between voltages of two-valued data output to the sense node SA.

Abstract: A latch type level shift circuit includes an internal power supply potential generating circuit for generating first and second internal power supply potentials; a latch circuit having first and second nodes and driven by the first and second internal power supply potentials; a level shifter having first and second output terminals and driven by the first internal power supply potential and a fixed potential; a first MOS transistor having a gate applied with the fixed potential; and a second MOS transistor having a gate applied with the fixed potential. The first MOS transistor is connected between the first node and the first output terminal, and the second MOS transistor is connected between the second node and the second output terminal.

Abstract: A semiconductor memory device includes a plurality of block cores which are each treated as one unit at the erase time, an R/D block core which is used instead of a memory cell array of a cor6responding one of the block cores in which a defect occurs, an R/D address storing section for storing an address of a defective block, and an R/D address comparing section for comparing an output signal of the R/D address storing section with an output signal of a block address buffer. If the result of comparison in the R/D address comparing section indicates “coincidence”, a block decoder in the R/D block core is set into a selected state and a block decoder in the defective block core is forcedly set into a non-selected state to replace the defective block core by the R/D block core.

Abstract: In a flash memory EEPROM, a memory cell MC is formed in a P-type semiconductor substrate. A peripheral transistor TR is formed in an N-type well. Another peripheral transistor TR is formed in a P-type well. The P-type well is by turn formed an N-type well and electrically insulated from the substrate. The substrate is typically provided with a metal back structure and its substrate voltage is set to predetermined voltages respectively for data erasure, data storage and data retrieval. With such an arrangement, the level of voltage stress with which the device is loaded during data erasure can be remarkably reduced to allow a down-sizing and an enhanced quality to be realized for the device.

Abstract: A semiconductor integrated circuit device has a data storage section for storing mode setting data corresponding to products of a plurality of types, redundancy data, and so on. The redundancy storage section is made up of a nonvolatile transistor for storing the mode setting data corresponding to the products, the redundancy data, etc., a latch circuit for latching data read out from the nonvolatile transistor and generating a mode signal, and a transmission gate for transmitting the data from read out from the nonvolatile transistor to the latch circuit. The semiconductor integrated circuit device also has an internal voltage generator for generating an internal voltage. This internal voltage is used as the power supply voltage of the data storage section.

Abstract: A nonvolatile semiconductor memory device comprises a row decoder circuit having first and second N-channel MOS transistors and first and second P-channel MOS transistors which correspond to each of word lines. One end of a source-to-drain current path of the first N-channel MOS transistor is connected to the word line, and the other end thereof is connected to a corresponding one of output terminals of a predecoder circuit. One end of a source-to-drain current path of the second N-channel MOS transistor is connected to the word line, and the other end thereof is supplied with a voltage of 0V or more in a data erase mode and is supplied with a low logical level signal in modes other than the data erase mode.

Abstract: A standby-mode booster circuit is activated in both a standby mode and an active mode and boosts up a power supply voltage to generate a booster voltage and output it from an output terminal. An active-mode booster circuit is activated in the active mode. In the active-mode booster circuit, an NMOS transistor is first turned on in response to a reset signal supplied from a reset signal generation circuit and then a connection node of capacitors is reset to the power supply voltage by the NMOS transistor. The boost operation is then started to output the booster voltage from the output terminal.

Abstract: A semiconductor memory device includes a plurality of block cores which are each treated as one unit at the erase time, an R/D block core which is used instead of a memory cell array of a corresponding one of the block cores in which a defect occurs, an R/D address storing section for storing an address of a defective block, and an R/D address comparing section for comparing an output signal of the R/D address storing section with an output signal of a block address buffer. If the result of comparison in the R/D address comparing section indicates “coincidence”, a block decoder in the R/D block core is set into a selected state and a block decoder in the defective block core is forcedly set into a non-selected state to replace the defective block core by the R/D block core.

Abstract: In a semiconductor memory device enabling to lower the source voltage, bit lines (BL) of a memory cell array (11) are selected by a column gate (12) and connected to sense amplifiers (13). Each sense amplifier (13) includes an operational amplifier (OP) having a sense node (SA) as one of its input terminals and a reference node (RE)to be shared with other sense amplifiers (13) as its other input terminal, an NMOS transistor (QN01) as a current source load interposed between the sense node (SA) and a power source (VCC) for each operational amplifier (OP), an NMOS transistor (QN02) as a current source load interposed between the reference node (REF) and the power source (VCC) for each operational amplifier (OP), and a reference voltage generating circuit (21) connected to the reference node (REF) and shared with other sense amplifiers (13) to generate a reference voltage of an intermediate level between voltages of two-valued data output to the sense node SA.

Abstract: A pattern constituted of a main bit line and four sub-bit lines is repeated around a column sub-selector of the flash EEPROM employing a double bit architecture having four block selection transistors per pitch of the pattern. In the flash EEPROM having a memory cell array and a column selector divided into a plurality of cell blocks 11i and a plurality of column sub selectors 12i, respectively, the column sub-selector including repeated patterns each having four sub bit lines (SBLs) and a single main bit line (MBL) arranged in a column direction. In a pitch of the repeating pattern, active regions for four block selection transistors (BSTs) are arranged. Gate wiring layers of each of the block selection transistors are arranged above the active region in a row direction and four block decode lines (BDLi) are arranged above the active region in the row direction.

Abstract: A nonvolatile semiconductor memory device includes a row decoder circuit having first and second N-channel MOS transistors and first and second P-channel MOS transistors which correspond to each of word lines. One end of a source-to-drain current path of the first N-channel MOS transistor is connected to the word line, and the other end thereof is connected to a corresponding one of output terminals of a predecoder circuit. One end of a source-to-drain current path of the second N-channel MOS transistor is connected to the word line, and the other end thereof is supplied with a voltage of 0V or more in a data erase mode and is supplied with a low logical level signal in modes other than the data erase mode.

Abstract: A voltage-level shifter has a first and a second power supply terminal to which a first and a second potential are supplied, respectively, the second potential being lower than the first potential; a first input terminal to which a first input signal is supplied, the first input signal having a high and a low level according to the first and the second potentials; a second input terminal to which a second input signal is supplied, the second input signal being an inverted signal of the first input signal.

Abstract: In a semiconductor memory device enabling to lower the source voltage, bit lines (BL) of a memory cell array (11) are selected by a column gate (12) and connected to sense amplifiers (13). Each sense amplifier (13) includes an operational amplifier (OP) having a sense node (SA) as one of its input terminals and a reference node (RE) to be shared with other sense amplifiers (13) as its other input terminal, an NMOS transistor (QN01) as a current source load interposed between the sense node (SA) and a power source (VCC) for each operational amplifier (OP), an NMOS transistor (QN02) as a current source load interposed between the reference node (REF) and the power source (VCC) for each operational amplifier (OP), and a reference voltage generating circuit (21) connected to the reference node (REF) and shared with other sense amplifiers (13) to generate a reference voltage of an intermediate level between voltages of two-valued data output to the sense node SA.

Abstract: A semiconductor integrated circuit device according to the present invention includes a booster circuit 1 for raising an external power supply voltage Vccext, a level detecting circuit 2 for detecting fluctuation in a stepped-up voltage Vccint2, an internal voltage generating circuit 3 for generating an internal voltage Vccint on the basis of the stepped-up voltage Vccint2, an address buffer 4, an address decoder 5, and a memory cell array 6 of an EEPROM structure. The level detecting circuit 2 includes a first level detecting part for performing level detection during a memory access state, and a second level detecting part for performing level detection during a stand-by state. During the stand-by state, the internal voltage generating circuit 3 short-circuits the stepped-up voltage Vccint2 and the internal voltage Vccint.

Abstract: The non-volatile semiconductor memory device comprises memory cell array having a plurality of memory cells, word lines connected to control gates of the memory cells, bit lines connected to drains of the memory cells, a source line connected in common to sources of the memory cells and connected to a well region where the memory cells are formed, a row decoder consisting of a row main decoder and a row sub-decoder for selecting a word line in the memory cell array, a column gate circuits for selecting a bit line in the memory cell array, a control gate driver for biasing a word line in the memory cell array, and an well driver for biasing semiconductor region in which the memory cell array is formed.

Abstract: A NOR type flash memory includes a plurality of word lines, a plurality of bit lines, at least one bit line, a plurality of nonvolatile memory cells, a row decoder, a cell selection circuit and a programming load. Each of the plurality of nonvolatile memory cells includes a gate electrode, drain electrode and source electrode and the gate electrode is connected to a corresponding one of the plurality of word lines, the drain electrode is connected to a corresponding one of the plurality of bit lines and the source electrode is connected to the source line. The row decoder selects one of the plurality of word lines at the time of data programming. The cell selection circuit includes a column decoder and column gates and is constructed to simultaneously select one bit line from each of the plurality of groups among the plurality of bit lines.

Abstract: A first voltage detection circuit detects whether a value of the power supply voltage is lower or higher than a first voltage, and generates a first signal according to the detection result. A second voltage detection circuit detects whether the power supply voltage is lower or higher than a second voltage higher than the first voltage, and generates a second signal according to the detection result. A control circuit receives the first and second signals, and conducts a control in such a manner that the control circuit ceases all the functions of an internal circuit when the first signal corresponds to a case where a value of the power supply voltage is lower than the first voltage, and ceases a part of the functions of the internal circuit when the first signal corresponds to a case where a value of the power supply voltage is higher than the first voltage and the second signal corresponds to a case where the value of the power supply voltage is lower than the second voltage.

Abstract: Each of first and second cell array groups has a cell array and a row decoder. Circuit blocks including a reset transistor, a Y selector, a write transistor, a block decoder, and a source decoder except the cell array and row decoder are arranged in the area between the first and second cell array groups. Since an address signal, a control signal, and a power supply common to the circuit blocks can be shared, the layout area can be reduced.

Abstract: In a booster circuit, a gate of an input-side transistor whose end is supplied with a power supply voltage is supplied with an inverted signal of a signal supplied to a signal input terminal of a booster unit at a first stage or supplied with an AND signal of the inverted signal and a booster circuit activation signal. Therefore, when the transistor at the first stage operates, the input-side transistor is turned off. Accordingly, a back flow of a current from inside the booster circuit to a power supply is prevented, so that the efficiency of the booster circuit can be improved. Further, fluctuations of the output voltage are not brought about even when the power supply voltage greatly fluctuates, so that the reliability of peripheral elements and memory cells can be improved and the allowable range of an external power supply voltage can be widened.

Abstract: A nonvolatile semiconductor memory device is provided in which a negative voltage is applied to a gate electrode of a memory cell transistor during an erase mode. The memory device includes a row decoder circuit having an N-channel transistor connected to a word line. The N-channel transistor is provided on a P-type well region of a semiconductor substrate. A negative voltage is applied to the P-type well region during the erase mode, while ground potential is applied thereto during another modes.