Renesas Technology Corp.

Mitsubishi Denki Kabushiki Kaisha

Renesas Electronics Corporation

Samsung Electronics Co., Ltd.

Hidenori Mitani

Taku Ogura

Tadaaki Yamauchi

Takashi Kubo

Kengo Aritomi

Takashi Ito

Tomoyuki Fujisawa

Shin-ichi Ishimoto

Hikaru Shibahara

Akihiko Kanda

Fumihiko Nitta

Takashi Kono

Takeshi Hamamoto

Koichi Takeda

Ken Matsubara

Tomoya Ogawa

Takashi Iwase

Satoru Tamada

Jun Setogawa

Masanori Nagahama

Takahiro Shimoi

Yoshinobu Kaneda

Toru Matsushita

Masaya Nakano

Fumiko Yamada

Speed enhancement of data reading is achieved while suppressing an influence of an offset voltage of a differential amplifier. The differential amplifier includes: a current source that is connected to a first power supply in which a suppliable current is a first current; an active element pair that is connected to the current source, and amplifies a signal input to an input terminal pair to output an output signal pair; a load element pair that is connected to a second power supply different in power supply voltage from the first power supply, the load element pair serving for outputting the output signal pair to an output terminal pair; and a capacitance element pair that is inserted between an external input terminal pair and the input terminal pair; a switching element pair that charges the capacitance element pair to generate a voltage, which is obtained by converting an offset voltage of the input terminal pair into an input voltage, in the capacitance element pair by short-circuiting corresponding terminals between the output terminal pair and the input terminal pair; and a current control circuit that controls a current suppliable by the current source to a second current larger than the first current at a time of performing the charge.

Differential amplifier, semiconductor device and offset cancellation method

A semiconductor device includes a semiconductor substrate having first and second edge lines, address pads along the first edge line, and memory mats, each including normal memory blocks and a spare memory block. Each normal memory block has nonvolatile memory cells and is a unit of batch erase. The memory mats are arranged in a U-shaped area having a hollow portion facing the second edge line. The device includes column decoders arranged correspondingly to the memory mats, an analog/logic circuit arranged in the hollow portion, and a power supply pad arranged between the analog/logic circuit and the second edge line. The analog/logic circuit includes a charge pump circuit. The device further includes a first power supply interconnection supplying power supply voltage to the charge pump circuit from the power supply pad, and a second power supply interconnection supplying power supply voltage to the column decoder from the power supply pad.

Semiconductor memory device having memory block configuration

Operational stability of the nonvolatile memory in plural power supply voltage modes set up in advance corresponding to the power supply voltage level is realized. A nonvolatile memory is configured with a memory array, a charge pump, a distributor for selecting an output voltage of the charge pump, and a sequencer for controlling operation of the charge pump and the distributor. The nonvolatile memory is also provided with an analyzer which notifies the sequencer of a power supply voltage mode selectively specified among plural power supply voltage modes set up in advance corresponding to power supply voltage levels, and which detects mismatch between the power supply voltage mode notified to the sequencer and an actually supplied power supply voltage and limits the operation of the charge pump and the distributor with the use of the sequencer, based on the detection result. An operational stability of the nonvolatile memory is realized.

Nonvolatile memory, data processing apparatus, and microcomputer application system

A memory apparatus includes a control circuit, a plurality of memory arrays, each of which contains a plurality of memory cells, and a current detecting circuit. The current detecting circuit measures a quantity of a current of a first memory array. A redundancy information is changed when the quantity of the current of the first memory array is over a first current quantity detected by the current detecting circuit. The control circuit controls an access to the memory arrays, and changes the access to the first memory array to a second memory array in accordance with the redundancy information.

A memory array including memory mats is arranged in a U shape when seen in two dimensions, and a logic circuit and an analog circuit are arranged in a region unoccupied by the memory array. This facilitates transmission of power supply voltage and signals between the peripheral circuit including the analog and logic circuits and the pad band including power supply and data pads. The analog circuit is positioned close to the power supply pad, so that voltage drop due to the resistance of power supply interconnection is restricted. It is also possible to separate a charge pumping power supply interconnection and a peripheral circuit power supply interconnection in the vicinity of the power supply pad.

A memory cell of a memory array stores two bits. A memory array sense amplifier provides two bits in a verify operation. Two bits in a page buffer stores a write target value for the corresponding memory cell. Each bit in a mask buffer stores a value defining processing to be effected on the corresponding memory cell. A write driver applies a write pulse when the bit in the mask buffer corresponding to the selected memory cell is '0'. A verify circuit compares the two bits provided from the memory array sense amplifier with the corresponding two bits in the page buffer, and changes the corresponding bit in the mask buffer from '0' to &#x201c;1&#x201d; when the result of the comparison represents matching.

Nonvolatile semiconductor memory device for writing multivalued data

When a data write sequence is started, initially, write data is latched in a data latch circuit corresponding to one memory mat. Then, a program pulse is applied to the memory mat, and data read from a memory cell, which is a data write target bit in the memory mat, is performed. Thereafter, verify determination of the memory mat is performed. After a verify operation for the memory mat is completed, a program pulse is applied to another memory mat, and a verify operation for another memory mat is performed.

Semiconductor memory device capable of achieving narrower distribution width of threshold voltages of memory cells and method of data write in the same

According to a method of erasing data in a non-volatile semiconductor memory device, block-round type overerase verify is performed. Specifically, overerase verify and write back are performed sequentially from a first address to a last address. That is, even when a write back pulse is applied after a certain address is selected and verify is performed, address increment from one address to another is performed, regardless of whether verify has been performed or not. Therefore, it is not that the same address is cumulatively rewritten, but write back to a memory cell corresponding to a defective address is sequentially and gradually performed. Accordingly, as write to a memory cell in an overerased state can evenly be performed, influence by off-leakage is suppressed, and a memory cell having threshold voltage distribution with less variation can be implemented.

Method of erasing data in non-volatile semiconductor memory device while suppressing variation

A multi-level semiconductor memory device for storing multi-level data having three or more values is implemented by utilizing a nonvolatile memory device for storing 2-valued data. Identification of successive 16-bit data externally applied is performed with external address bit AA [, and a storage block is selected with external address bit AA [. Upper word data LW and lower word data UW are compressed into byte data of 8 bits, respectively, and stored in a memory cell array.

Semiconductor memory device

Until the number of pulse application n reaches 12, as a first-half pulse, a pulse is set to have a width fixed to 2 ms, and its voltage is increased every time. As a latter-half pulse, the pulse is set to have a width fixed to 3 ms and the pulse voltage is increased every time until the maximum voltage is attained. After the maximum voltage is attained, first, the pulse of a width of 3 ms is applied twice, the pulse of a width of 4 ms with the maximum voltage is applied twice, and the pulse of a width of 5 ms with the maximum voltage is applied twice. Even after the maximum voltage is attained, change over time of a threshold voltage can be more linear. Thus, a non-volatile semiconductor memory device allowing efficient programming operation and erasing operation in a short period of time can be provided.

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Hyogo, Japan

Hidenori Mitani