Mitsubishi Denki Kabushiki Kaisha

Renesas Technology Corp.

Kunihiko Kozaru

Tomohisa Wada

Tadaaki Yamauchi

Hirotoshi Sato

Shigeki Ohbayashi

Atsushi Ohba

Tadato Yamagata

Motomu Ukita

Toru Shiomi

Tadayuki Shimizu

Koreaki Fujita

Takashi Sekiya

Yoshiyuki Haraguchi

If a region designated by an address signal is a logic control region, an interface portion transmits/receives data to/from a register instead of a DRAM. A data signal used at that time is a control command for a logic circuit held in the register or input data for a process in the logic circuit. Depending on the content held in the register, the logic circuit performs, for example, an encryption process or a process which takes for a microcomputer a long time to complete such as an image processing. The result of processing is stored in the register and read in a sequence of reading from the DRAM.

Semiconductor memory device internally provided with logic circuit which can be readily controlled and controlling method thereof

A substrate pad VREFT provided outside of the mold resin and word line driving voltage generation circuits within a plurality of bare chips are electrically connected only through electrical wires on a module substrate. Therefore, it becomes possible to force a voltage to the word line driving voltage generation circuits from the outside not only after the plurality of bare chips is mounted on the module substrate but also after the plurality of bare chips is integrally covered with mold resin by applying a desired voltage to the substrate pad VREFT. There is provided a semiconductor memory module capable of performing a test for a semiconductor chip after the semiconductor chip is mounted on a module substrate.

Semiconductor memory module

An interface circuit performs supply/reception of data with a register instead of supply/reception of data with DRAM when an area specified by an address signal is a logic control area. Data signals in the case are a control command for a logic circuit held in a register and input data to be processed. The logic circuit takes charge of a critical path in processing time such as cryptographic processing and image processing. A processing result is held in the register. The register circuit switches between storage data stored in DRAM and data given from a terminal group to select data to be processed according to a control signal.

Simply interfaced semiconductor integrated circuit device including logic circuitry and embedded memory circuitry operative with a reduced number of pin terminals

A semiconductor device includes a sense amplifier which becomes able to amplify a signal when receiving a read enable signal; a delay unit which can provide a plurality of transmission paths having different delay times and which propagates the read enable signal through a transmission path corresponding to a selection signal among the plurality of transmission paths; a selection signal generation circuit capable of generating the plurality of selection signals; and a JTAG boundary scan test circuit which brings the selection signal generation circuit into operation in accordance with a instruction.

Selectable sense amplifier delay circuit and method

A semiconductor memory device includes a programming mode detecting circuit for detecting a programming mode, a word configuration programming circuit which can be programmed with a word configuration in the programming mode, and a word configuration selecting circuit for selecting a word configuration based on the programmed word configuration. Therefore, in the semiconductor memory device, a word configuration can be set even after molding.

Word configuration programmable semiconductor memory with multiple word

In a synchronous semiconductor memory device, a predecoder is provided between a former stage address input register formed of first latch circuits and a latter stage address input register formed of second latch circuits. The first and second latch circuits operate in response to first and second internal clock signals complementary to each other. A predecode signal can be latched by the second latch circuit even when the generation of the predecode signal is not in time for the rise of the second internal dock signal due to delay of the input of an external address signal. Accordingly, the set up time for the external address signal can be reduced.

Synchronous semiconductor memory device having set up time of external

Predetermined bits of an address signal taken into an address register are taken into a burst address counter and are changed in synchronization with a clock signal. The address bits from the burst address counter are applied to a block decoder for selecting a memory sub-array from the plurality of memory sub-arrays. A block address and the memory sub-array to be selected change at every clock cycle. An operation frequency of data read circuits provided for the respective memory sub-arrays can be made lower than a frequency of the clock signal. Memory cell data can be read out accurately even in a high-frequency operation.

Synchronous semiconductor memory device operable in a burst mode

A semiconductor memory device includes a plurality of external power supply pads P1 to P3. Connection between external power supply pads P1 to P3 and an external power supply is determined in accordance with the voltage of the external power supply to be used, and the connection is switched by bonding. External power supply of a high voltage level is connected to an external power supply pad P2 which is connected to VDC1 and VDC2. A circuit including memory cells operates using the voltage applied from VDC1 or external power supply pad P3, while a group of word line drivers operates using the voltage applied from VDC2 or external power supply pad P1. VDC1 down converts the external power supply voltage, and VDC2 down converts it in accordance with the level of the voltage of the external power supply voltage, and generates internal power supply voltages, respectively. Accordingly, a semiconductor memory device which operates adapted to different external power supplies can be obtained.

Semiconductor memory device adaptable to external power supplies of

In repairing a defective memory cell of a data memory placed in a data memory region, a repairing circuit which employs a repairing method causing some access penalty but having high repairing efficiency is located in a redundant row region and a redundant column region in the data memory region. On the other hand, in repairing a defective memory cell of a tag memory placed in a tag memory region, a repairing circuit which employs a repairing method having low repairing efficiency but causing little access penalty is located in a redundant column region in the tag memory region. Accordingly, optimal repair of a defective memory cell can be achieved according to respective functions of the tag memory and the data memory.

Semiconductor memory device including a tag memory

A reference voltage generated in a Vref1 generating circuit is supplied from a corresponding applied voltage selector to respective backgates of access transistors in each SRAM cell constituting a column which is selected by a column decoder. On the other hand, a substrate voltage generated in a Vbb generating circuit is supplied from a corresponding applied voltage selector to respective backgates of access transistors in each SRAM cell constituting a column which is not selected by the column decoder.

Semiconductor memory device capable of reducing power consumption

A pair of driving bipolar transistors of a lateral type T1 and T2 have emitters coupled to a ground potential, collectors connected to a pair of highly resistive elements R1 and R2. Highly resistive elements R1 and R2 have respective other ends coupled to power supply potential V.sub.CC, and bases and collectors of transistors T1 and T2 are cross-connected to each other, thereby forming a flipflop circuit. Access MOS transistors Q3 and Q4 having a gate potential controlled by word line WL are each connected to form a conduction path between one of storage nodes A and B and one of the pair of bit lines BL and /BL.

Static type semiconductor memory device capable of operating at a low

A static RAM includes: a memory cell array including word lines, bit line pairs and memory cells; a row recorder; a column decoder; a DTD signal generator responsive to transition of input data or transition of a write enable signal for generating a data transition detection signal for a prescribed time period; and a write driver responsive to the write enable signal and the data transition detection signal for supplying the input data to a bit line pair selected by the column decoder. Even when there is a noise in write enable signal during reading cycle and data transition detection signal is generated erroneously, erroneous writing of data can be prevented, since write enable signal is not supplied to the write driver.

Semiconductor memory device having data transition detecting function

A dynamic random access memory includes memory cell array blocks, row decoders, redundant word lines, redundant memory cells, replacement circuits, and a normal memory cell de-select circuit. Each memory cell array block includes normal word lines and normal memory cells. Each row decoder is provided corresponding to one memory cell array block. Any of the redundant word line is provided corresponding to one memory cell array block. Each replacement circuit includes a redundancy select circuit, a replacement address program circuit, and a redundant word line select circuit. The redundancy select circuit has set in advance whether a corresponding redundant word line is to be used or not. The program circuit has an address programmed of a normal word line to be replaced with a corresponding redundant word line. The normal memory cell de-select circuit inactivates a row decoder in response to an output of the replacement circuit when any replacement circuit selects a corresponding redundant word line. When a corresponding redundant word line is not used, a predecode signal is distributed to a program circuit so that the loads of a predecode signal are equal to each other.

Semiconductor memory device including improved redundancy circuit

An NAND gate for outputting an output establishment detection signal in response to the fact that a complementary output of a latch type sense amplifier has been established is provided. When a tristate buffer is activated by signal, a word line which has been in a selected state is rendered non-selected state. Accordingly, current can be prevented from leaking from a power supply line to a ground line in tristate buffer. In addition, column current Ic flowing through memory cells can be minimized in response to the fact that word line has been set to a selected state.

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Hyogo, Japan

Kunihiko Kozaru