Mitsubishi Denki Kabushiki Kaisha

Other

Renesas Technology Corp.

Renesas Electronics Corporation

Yasuhiko Taito

Akira Yamazaki

Fukashi Morishita

Nobuyuki Fujii

Mihoko Akiyama

Mako Okamoto

Mako Kobayashi

Masaaki Mihara

Naoki Otani

Kayoko Omoto

Kenji Koda

Tsukasa Ooishi

Hiroshi Yoshida

Shinichi Kobayashi

Hiroshi Kato

Masamichi Fujito

Jun Ohtani

Shinji Kawai

Takanori Takahashi

Tsukasa Oishi

Katsumi Dosaka

Takeshi Hamamoto

Tomohisa Wada

Yoshikazu Miyawaki

Takeshi Fujino

Masaru Haraguchi

Masashi Wada

Akinori Matsuo

Tomoya Ogawa

Tetsuo Kato

Takashi Kurafuji

Tomohisa Iba

Masashi Muto

Eiji Sakuma

A storage device includes a data memory unit and a status memory unit. The data memory unit includes a pair of flash memory cells to be read by a complementary read mode, and 1-bit data is stored therein by the pair of flash memory cells. The status memory unit includes a flash memory cell to be read by a reference read mode, and a status flag is stored therein by the flash memory cell.

Storage device and storage method

A controlling method of a semiconductor device provided with a memory array including a plurality of complementary cells, each cell including a first memory element and a second memory element, for holding binary data depending on a difference of threshold voltage therebetween, the controlling method comprising: performing a prewrite procedure that writes '0' or '1' to both of the first memory element and the second memory element.

Semiconductor device and control method of the semiconductor device

A semiconductor device includes a memory array having a plurality of complementary cells, each including a first memory element and a second memory element, for holding binary data depending on a difference of threshold voltage therebetween, and a control circuit for initializing the complementary cells. The control circuit performs a first initialization control of reducing the threshold voltage of both the first memory element and the second memory element of the complementary cell and changing the threshold voltage of at least one of the first memory element and the second memory element at an intermediate level lower than a first writing level and higher than an initialization level, a first writing control of changing the threshold voltage of one of the first memory element and the second memory element of the complementary cell at the first writing level, and a second initialization control of changing the threshold voltage of both the first memory element and the second memory element of the complementary cell at the initialization level.

There is provided a semiconductor device of which the circuit scale does not significantly increase even with an ECC function. A microcomputer having an internal flash memory inserts one weight in a sense amplifier activation signal only when an error detection signal is on the H level at a given time in a read cycle or when the error detection signal which was on the H level in a previous read cycle has shifted to the L level in a current read cycle. This allows the retrieval of output data signals after waiting till the output data signals through error correction are determined only when an error is contained in the output data signals.

Semiconductor memory having embedded microcomputer with ECC function

With this flash memory, because a plurality of memory blocks are formed on a surface of a single P-type well, a layout area can be made small. Further, when erasing data for a memory block to be erased, a voltage of the P-type well is applied to all word lines of a memory block to be not erased. Consequently, the voltage of the P-type well and the voltage of all word lines of the memory block to be not erased change at the same time. With this, it is possible to prevent a threshold voltage for the memory block to be not erased from changing.

Nonvolatile semiconductor memory device

A semiconductor flash memory includes an erase/write control unit that, when performing an erase/write operation of read memory cells, reads and senses memory current of the read memory cells for each memory cell, and adjusts threshold voltage of each of the read memory cells to a predetermined value, and a readout control unit that, when performing a read operation, selects at least two read memory cells simultaneously from among the read memory cells to which the erase/write control unit stored the same data, and senses total memory current for the at least two read memory cells.

Semiconductor flash memory

At the time of an operation of writing data to a specific memory cell in a memory block, a semiconductor memory device applies a write voltage for a predetermined period and, after that, performs a verifying operation by using a sense amplifier circuit and a comparator. When it is found as a result of the verifying operation that writing to the memory cell is insufficient, the writing operation is performed again by an instruction of a memory control circuit. At this time, the memory control circuit adjusts a write voltage.

Nonvolatile semiconductor memory device capable of uniformly inputting/outputting data

Well bias voltages are generated in accordance with a logic power supply voltage and a memory power supply voltage. The transistor included in a control circuit in a memory core is constituted of a logic transistor manufactured through the same manufacturing steps as those for the transistors of a logic formed on the same semiconductor substrate. Well bias voltages (VBB, VPP) are applied to a back gate of this logic transistor. A memory integrated with a logic on a common semiconductor substrate is provided which allows a transistor of a control circuit therein to be manufactured through the same manufacturing process as that of the logic and allows reduction of current consumption.

Semiconductor device with multiple power sources

The clock-generating circuit for generating a clock signal, includes a ring oscillator having an odd number of inverters connected in a ring configuration. The ring oscillator is activated to generate a clock signal when an activating signal is at a first level and is de-activated to cease generation of the clock signal when the activating signal is at a second level. A latch circuit is connected to an output node of the ring oscillator, and holds a level of the output node of the ring oscillator in response to transition of the activating signal from the first level to the second level. When the activating signal is lowered from the H level to the L level, the level of the clock signal is latched such that generation of a glitch in the clock signal will be prevented from occurring.

Clock generating circuit

N-channel MOS transistors in a read gate circuit have respective sources connected to a sense amplifier activation line of a sense amplifier, not to a ground node. A read column selection line is selected prior to activation of the sense amplifier. Accordingly, paired read data lines are driven simultaneously with the activation of the sense amplifier.

Semiconductor memory device achieving fast random access

A VDC circuit that supplies an internal voltage VDD to an internal circuit in a normal operation forces a transistor off in a burn-in test mode through input of a test signal to suppress supply of an external power supply voltage VDDH to a node. In a burn-in test mode, an external power supply voltage lower than external power supply voltage VDDH and higher than internal voltage VDD is supplied from an external pad.

Semiconductor integrated circuit with voltage down converter adaptable for burn-in testing

With power-on detection circuits provided for a plurality of power supply voltages, a main power-on detection signal is maintained at the active state to reset an internal node while at least one of the power-on detection signals is active. In a multi-power semiconductor integrated circuit device, current consumption at the time of power-up is reduced.

Multi-power semiconductor integrated circuit device

Growing community of inventors

Hyogo, Japan

Yasuhiko Taito