Reference Or Dummy Element Patents (Class 365/210.1)
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Patent number: 8144538Abstract: A semiconductor device to improve layout uniformity may include an active region formed in a substrate, a dummy active region formed in the substrate and separated from the active region, a word line crossing over the active region, and a dummy word line. The dummy word line is formed over the dummy active region to overlap at least part of the dummy active region and may have an end positioned within the dummy active region.Type: GrantFiled: January 15, 2009Date of Patent: March 27, 2012Assignee: Samsung Electronics Co., Ltd.Inventor: Sung Hoon Kim
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Patent number: 8143653Abstract: A phase-change random access memory device is provided. The phase-change random access memory device includes a global bit line connected to a write circuit and a read circuit, multiple local bit lines, each being connected to multiple phase-change memory cells, and multiple column select transistors selectively connecting the global bit line with each of the multiple local bit lines, each column select transistor having a resistance that varies depending on its distance from the write circuit and the read circuit.Type: GrantFiled: November 16, 2009Date of Patent: March 27, 2012Assignee: Samsung Electronics Co., Ltd.Inventors: Woo-Yeong Cho, Jong-Soo Seo, Young-Kug Moon, Jun-Soo Bae, Kwang-Jin Lee
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Patent number: 8144500Abstract: According to one embodiment, semiconductor memory device includes: semiconductor substrate; parallel first lines stacked on substrate; parallel second lines intersecting first lines; memory cell array including memory cells at intersections of first and second lines and each including variable resistance element and selecting element series-connected together; first control circuit provided in second region of substrate adjoining first region immediately under array; second control circuit provided in first region of substrate; and dummy lines formed in same layer as second lines, such that they intersect first lines in region above first control circuit. First control circuit applies first voltage to selected first line. Second control circuit applies second voltage lower than first voltage to selected second line, and to dummy lines, third voltage by which potential difference applied to memory cells at intersections of selected first line and dummy lines becomes lower than on-voltage of selecting element.Type: GrantFiled: September 7, 2010Date of Patent: March 27, 2012Assignee: Kabushiki Kaisha ToshibaInventor: Fumihiro Kono
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Publication number: 20120069629Abstract: According to one embodiment, a semiconductor memory device includes a first reference cell being arranged in a first cell array, and a plurality of first fuse cells being arranged in the first cell array. The first reference cell and the plurality of first fuse cells are arranged on the same row or column.Type: ApplicationFiled: September 16, 2011Publication date: March 22, 2012Inventors: Yoshihiro UEDA, Akira KATAYAMA, Ryousuke TAKIZAWA
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Publication number: 20120069636Abstract: A method is for reading a first bit cell of a static random access memory in which the static random access memory has a first plurality of bit cells including the first bit cell. Each bit cell of the first plurality of bit cells includes a cross coupled pair of inverters for storing a logic state, optimized for being written, and powered by a read voltage during a read of the first plurality of bit cells. Each bit cell of the first plurality of bit cells is coupled to a true read bit line and a true write bit line, and a second plurality of bit cells is coupled to a complementary read bit line and a complementary write bit line. The true and complementary read bit lines are precharged to a precharge voltage of about half the read voltage. The true read bit line is predisposed to a logic low condition.Type: ApplicationFiled: September 16, 2010Publication date: March 22, 2012Inventors: Perry H. Pelley, Ravindraraj Ramaraju
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Patent number: 8139409Abstract: Embodiments of the invention relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to generate access signals to facilitate memory operations in scaled arrays of memory elements, such as memory implemented in third dimensional memory technology formed BEOL directly on top of a FEOL substrate that includes data access circuitry. In at least some embodiments, a non-volatile memory device can include a cross-point array having resistive memory elements disposed among word lines and subsets of bit lines, and an access signal generator. The access signal generator can be configured to modify a magnitude of a signal to generate a modified magnitude for the signal to access a resistive memory element associated with a word line and a subset of bit lines. The modified magnitude can be a function of the position of the resistive memory element in the cross-point array.Type: GrantFiled: January 29, 2010Date of Patent: March 20, 2012Inventors: Christophe Chevallier, Chang Hua Siau
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Patent number: 8134881Abstract: A non volatile memory device comprises memory cells such as MRAM cells, reading circuits and a reference cell for generating a reference for use by the reading circuits, and can determine if the reference is degraded by thermal instability. This can help reduce a data error rate. Detecting such degradation can prove to be more effective than trying to design in enough margins for the lifetime of the device. The reference cell can be less susceptible to degradation than other cells by using different shape of cells and different write currents. Where each reference cell is used by many memory cells, the reference cell tends to be used more often than any particular memory cell and so can be more susceptible to degradation. Another way of ensuring against longer term degradation of the reference is periodically rewriting the reference cell.Type: GrantFiled: April 23, 2010Date of Patent: March 13, 2012Inventor: Hans Marc Bert Boeve
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Patent number: 8134866Abstract: A method programs a phase change memory device. The method comprises receiving program data for selected memory cells; generating bias voltages based on reference cells; sensing read data stored in a selected memory cell by supplying the selected memory cell with verification currents determined by the bias voltages; determining whether the read data is identical to the program data; and upon determining that the program data for one or more of the selected memory cells is not identical to the corresponding read data, iteratively applying a write current to the one or more selected memory cells.Type: GrantFiled: January 6, 2010Date of Patent: March 13, 2012Assignee: Samsung Electronics Co., Ltd.Inventors: Jun-Soo Bae, Kwang-Jin Lee, Beak-Hyung Cho, Woo-Yeong Cho, Hye-Jin Kim
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Patent number: 8130582Abstract: A unit operator cell includes a plurality of SOI (Silicon on Insulator) transistors, write data is stored in a body region of at least two SOI transistors, and the storage SOI transistors are connected in series with each other to a read port or each of the storage SOI transistors is singly connected to the read port. Therefore, an AND operation result or a NOT operation result of data stored in the unit operator cells can be obtained, and operation processing can be performed only by writing and reading data. A semiconductor signal processing device that can perform logic operation processing and arithmetic operation processing at high speed is implemented with low power consumption and a small occupation area.Type: GrantFiled: February 20, 2009Date of Patent: March 6, 2012Assignee: Renesas Electronics CorporationInventors: Hiroki Shimano, Kazutami Arimoto
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Patent number: 8130539Abstract: A phase change memory device includes a signal generator configured to generate first and second sensing and amplifying enable signals which are sequentially activated during an activation period of a word line selection signal and each of which has a certain activation period length, a resistance sensor configured to sense a resistance value by applying a certain operation current to a phase change memory cell corresponding to the word line selection signal during an activation period of the first sensing and amplifying enable signal and a voltage level amplifier configured to logically determine a voltage level of the resistance sensing signal based on a voltage level of a logic reference signal during an activation period of the second sensing.Type: GrantFiled: June 19, 2009Date of Patent: March 6, 2012Assignee: Hynix Semiconductor Inc.Inventor: Hyuck-Soo Yoon
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Patent number: 8130584Abstract: The present invention provides a semiconductor memory and a control method therefor, the semiconductor device including a first current-voltage conversion circuit (16) connected to a core cell (12) provided in a nonvolatile memory cell array (10), a second current-voltage conversion circuit (26) connected to a reference cell (22) through a reference cell data line (24), a sense amplifier (18) sensing an output from the first current-voltage conversion circuit and an output from the second current-voltage conversion circuit, a compare circuit (28) comparing a voltage level at the reference cell data line with a predefined voltage level, and a charging circuit (30) charging the reference cell data line, if the voltage level at the reference cell data line is lower than the predefined voltage level during pre-charging the reference cell data line. According to the present invention, the pre-charging period of the reference cell data line can be shortened, and the data read time can be shortened.Type: GrantFiled: October 15, 2010Date of Patent: March 6, 2012Assignee: Spansion LLCInventors: Akira Ogawa, Masaru Yano
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Patent number: 8125844Abstract: A semiconductor memory device includes a first cell array including a plurality of unit cells and a bit line sense amplifying unit for sensing and amplifying data signals stored in the unit cells. Each unit cell is provided with a PMOS transistor and a capacitor. Therefore, the semiconductor memory device efficiently operates with low voltage without any degradation of operation speed.Type: GrantFiled: October 13, 2009Date of Patent: February 28, 2012Assignee: Hynix Semiconductor Inc.Inventors: Hee-Bok Kang, Jin-Hong Ahn, Sang-Don Lee
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Patent number: 8125845Abstract: Even when memory capacity of a memory that uses a replica bit-line is made higher, fluctuations of a generating timing of a sense-amplifier enable signal are reduced. A semiconductor integrated circuit device comprises a plurality of word lines, a plurality of bit-lines, a plurality of ordinary memory cells, an access control circuit, a plurality of sense-amplifiers, first and second replica bit-lines, first and second replica memory cells, and first and second logic circuits. The first and second replica memory cells are connected to the first and second replica bit-lines, respectively; inputs of the first and second logic circuits are connected to the first and second replica bit-lines, respectively; a sense-amplifier enable signal is generated from an output of the second logic circuit; and this signal is supplied to a plurality of sense-amplifiers.Type: GrantFiled: January 14, 2010Date of Patent: February 28, 2012Assignee: Renesas Electronics CorporationInventors: Shigenobu Komatsu, Masanao Yamaoka, Noriaki Maeda, Masao Morimoto, Yasuhisa Shimazaki
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Publication number: 20120044755Abstract: In a particular embodiment, a method of testing a reference cell in a memory array includes coupling a first reference cell of a first reference cell pair of the memory array to a first input of a first sense amplifier of the memory array. The method also includes providing a reference signal to a second input of the first sense amplifier. The reference signal is associated with a second reference cell pair of the memory array.Type: ApplicationFiled: August 23, 2010Publication date: February 23, 2012Applicant: QUALCOMM INCORPORATEDInventors: Jung Pill Kim, Tae Hyun Kim, Hari M. Rao
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Patent number: 8116119Abstract: A static random access memory (SRAM) can include a plurality of columns forming a memory array, wherein each column comprises a plurality of memory cells coupled to bitlines and wordlines, and a write replica circuit generating a signal when data has been written to the write replica circuit. A wordline of the memory array is turned off responsive to the signal. The write replica circuit can include an additional column comprising at least one dual port dummy memory cell, and write detection circuitry coupled to the dual port dummy memory cell detecting when data has been written to the dual port dummy memory cell and responsively generating the signal. The signal generated by the write detection circuitry indicates a successful write operation to the dual port dummy memory cell.Type: GrantFiled: April 12, 2010Date of Patent: February 14, 2012Assignee: Xilinx, Inc.Inventors: Tao Peng, Hsiao Hui Chen
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Publication number: 20120033518Abstract: Source-side sensing techniques described herein determine the data value stored in a memory cell based on the difference in current between the read current from the source terminal of the memory cell and a sink current drawn from the read current. The sink current is drawn in response to the magnitude of a reference current provided by a reference current source such as a reference cell.Type: ApplicationFiled: October 19, 2011Publication date: February 9, 2012Applicant: Macronix International Co., Ltd.Inventors: Chun-Hsiung Hung, Han-Sung Chen, Chung-Kuang Chen
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Publication number: 20120036315Abstract: A memory circuit comprises a memory array including a plurality of memory cells, multiple word lines, and at least one bit line. Each of the memory cells is coupled to a unique pair of a bit line and a word line for selectively accessing the memory cells. The memory circuit further includes at least one control circuit coupled to the word lines and operative to selectively change an operation of the memory array between a first data storage mode and at least a second data storage mode as a function of at least one control signal supplied to the control circuit. In the first data storage mode, each of the memory cells is allocated to a corresponding stored logic bit, and in the second data storage mode, at least two memory cells are allocated to a corresponding stored logic bit.Type: ApplicationFiled: August 9, 2010Publication date: February 9, 2012Applicant: International Business Machines CorporationInventors: William R. Reohr, Darren L. Anand, Mark D. Jacunski
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Patent number: 8102713Abstract: The invention provides circuits, systems, and methods for monitoring a non-volatile memory (NVM) cell, or an array of NVM cells. The monitor is capable of switching from a normal operating state to an evaluation state, monitoring for one or more particular characteristics, and returning to the normal operating state. Alternative embodiments of the invention are disclosed using various triggers and producing outputs capable of reporting or feeding back to influence the operation of the monitoring systems and methods, the NVM circuitry, or an external system. The invention includes an energy conservation feature, in that no power is consumed in the normal operating state, and low power in the evaluation state.Type: GrantFiled: June 25, 2009Date of Patent: January 24, 2012Assignee: Triune IP LLCInventors: Ross E. Teggatz, Wayne T. Chen, Brett Smith
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Patent number: 8093668Abstract: A magnetoresistive random access memory includes first and second magnetoresistive effect element. A shape of the first magnetoresistive effect element has a first length in a first direction and a second length in a second direction. The second length is equal to or greater than the first length. A ratio of the second length to the first length is a first value. The second magnetoresistive effect element is used to determine a resistance state of the first magnetoresistive effect element. A shape of the second magnetoresistive effect element has a third length in a third direction and a fourth length in a fourth direction. The fourth length is equal to or greater than the third length. A ratio of the fourth length to the third length is a second value which is greater than the first value.Type: GrantFiled: June 13, 2008Date of Patent: January 10, 2012Assignee: Kabushiki Kaisha ToshibaInventor: Yoshihiro Ueda
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Patent number: 8089811Abstract: Flash memory devices include a first memory cell string including a plurality of serially-connected memory cells and first and second serially-connected dummy transistors configured to couple the serially-connected memory cells to a bit line and a second memory cell string including a plurality of serially-connected memory cells and first and second serially-connected dummy transistors configured to couple the serially-connected memory cells to the bit line. The first dummy memory cells of the first and second memory cell strings have gates connected in common to a first dummy word line and have different threshold voltages and the second dummy memory cells of the first and second memory cell strings have gates connected in common to a second dummy bit line and have different threshold voltages.Type: GrantFiled: October 16, 2009Date of Patent: January 3, 2012Assignee: Samsung Electronics Co., Ltd.Inventors: Myoung Gon Kang, Kitae Park
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Patent number: 8089812Abstract: A semiconductor memory device can reduce a circuit area necessary for row repair. The semiconductor memory device includes a plurality of memory banks, a plurality of cell arrays arranged in each of the memory banks, a plurality of array word lines arranged in each of the cell arrays, one or more repair word lines arranged in each of the cell arrays, and a plurality of repair information storages configured to store bank information and row addresses of the array word lines to be replaced with the repair word lines.Type: GrantFiled: December 31, 2007Date of Patent: January 3, 2012Assignee: Hynix Semiconductor Inc.Inventors: Dong-Keun Kim, Jee-Eun Lee
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Patent number: 8085573Abstract: A ferroelectric memory of an embodiment of the present invention includes a plurality of units, in each of which a ferroelectric capacitor and a transistor are connected to each other in parallel.Type: GrantFiled: September 18, 2009Date of Patent: December 27, 2011Assignee: Kabushiki Kaisha ToshibaInventor: Shinichiro Shiratake
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Publication number: 20110310678Abstract: An output current of a memory cell is sensed by a sensing circuit for distinguishing a program state and an erase state of the memory cell. The sensing circuit includes a reference transistor, a P-type MOSFET, and an N-type MOSFET. The P-type MOSFET has a gate connected to a memory cell for receiving an output current of the memory cell. The N-type MOSFET has a drain connected to a drain of the first P-type MOSFET, and has a source connected to ground. The inverter has an input terminal connected to the drain of the first N-type MOSFET. The voltage at an output terminal of the inverter is used for indicating the program state or the erase state of the memory cell. The reference transistor has a gate connected to a reference signal, and has a drain connected to the gate of the P-type MOSFET.Type: ApplicationFiled: June 16, 2010Publication date: December 22, 2011Inventor: Yih-Lang Lin
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Patent number: 8077493Abstract: A semiconductor memory device includes a memory cell array disposing a plurality of memory cells at each intersection of word lines and bit lines, the memory cell including one pair of cross-connected inverters including a transistor, a first dummy transistor having a threshold voltage which has a certain relationship with a threshold voltage of the transistor of the memory cell, a dummy bit line connected to one end of the first dummy transistor, and the dummy bit line charged so as to have a predetermined voltage, a dummy transistor control circuit configured to control conduction of the first dummy transistor, and a word line driver configured to supply a word line voltage to the word line connected to the selected memory cell, and the word line driver configured to change a rise time of the word line voltage in accordance with a change in a voltage of the dummy bit line.Type: GrantFiled: December 10, 2009Date of Patent: December 13, 2011Assignee: Kabushiki Kaisha ToshibaInventor: Akira Katayama
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Patent number: 8068367Abstract: Systems, methods, and devices are disclosed, including an electronic device that includes a first data location, a quantizing circuit, and a reference current source, all coupled to an electrical conductor. The reference current source may include a current mirror with a side coupled to the electrical conductor and a second data location coupled to another side of the current mirror.Type: GrantFiled: June 15, 2007Date of Patent: November 29, 2011Assignee: Micron Technology, Inc.Inventor: R. Jacob Baker
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Patent number: 8064262Abstract: A semiconductor device in accordance with one embodiment of the invention can include a first data storage region including a non-volatile main data storage region. Additionally, the semiconductor device can include a second data storage region including a non-volatile reference region wherein an erasing operation and a writing operation are performed on both the first data storage region and the second data storage region. Moreover, the semiconductor device can also include a control unit coupled to the first and second data storage regions which determines a stress condition corresponding to the first data storage region based on a stress information related to the second data storage region.Type: GrantFiled: September 18, 2008Date of Patent: November 22, 2011Assignee: Spansion LLCInventor: Minoru Yamashita
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Patent number: 8059480Abstract: A semiconductor memory device includes a plurality of memory cells configured to correspond to each of a plurality of word lines for storing data; a plurality of reference memory cells configured to include first and second magnetic memory devices, whose lower electrodes are commonly connected to each other, to generate a reference current corresponding to each of the memory cells; and a sense amplification unit configured to sense and amplify the reference current and a data current corresponding to a memory cell connected to an activated word line among the word lines.Type: GrantFiled: June 22, 2009Date of Patent: November 15, 2011Assignee: Hynix Semiconductor Inc.Inventors: Sung-Yeon Lee, Young-Hoon Oh
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Patent number: 8059481Abstract: A semiconductor memory device includes a memory cell array provided with a main memory cell array including a plurality of memory cells, and a dummy column including a plurality of dummy memory cells, a dummy readout current control section configured to control a current value of a dummy readout current of the dummy memory cell in such a manner that the current value becomes between the current values of the readout currents in first and second states of the memory cell, and a sense section provided with a sense amplifier configured to receive a readout current in one of the first and second states, or dummy readout current as an input, comparing these currents with each other, and outputting the currents.Type: GrantFiled: September 8, 2009Date of Patent: November 15, 2011Assignee: Kabushiki Kaisha ToshibaInventor: Tomohiro Kobayashi
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Publication number: 20110273922Abstract: A memory circuit includes a first memory cell node capacitor, a first memory cell node transistor, a second memory cell node having a second memory cell node capacitor and a second memory cell node transistor, and a pre-charging circuit for pre-charging the first and second memory cell nodes to first and second voltage levels, respectively. The circuit includes a reference memory cell having first and second reference cell transistors with an equalizing transistor between, and a sense amplifier that detects a potential difference between reference bit lines from the reference memory cell and the first or second memory cell node, respectively. The reference cell transistors and equalizing transistor perform a first voltage equalization of the memory cell nodes at a predetermined voltage and a second voltage equalization of the memory cell nodes based on first or second reference signals respectively input to the first or second reference cell transistor.Type: ApplicationFiled: August 16, 2010Publication date: November 10, 2011Applicant: STMICROELECTRONICS PVT. LTD.Inventors: Sanjay Kumar YADAV, G. Penaka Phani, Shallendra Sharad
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Patent number: 8054668Abstract: In an illustrative embodiment, a memory cell comprises a first and a second MOSFET, wherein the first MOSFET undergoes a process to modify the threshold voltage such that a modified threshold voltage represents a first stored logic value. By determining which one of the first and the second MOSFETs has an altered threshold voltage, the stored logic value is determinable. The threshold voltage of the first MOSFET is altered by supplying current through a MOSFET gate, causing a gate heating effect that results in a threshold voltage shift.Type: GrantFiled: October 30, 2008Date of Patent: November 8, 2011Assignee: Agere Systems Inc.Inventor: Edward B. Harris
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Patent number: 8051342Abstract: A semiconductor memory device including: a memory cell array including a plurality of word lines, a plurality of bit lines, and memory cells arranged in portions where the plurality of word lines and the plurality of bit lines intersect with each other; a plurality of data bus lines connected to the plurality of bit lines; a plurality of sense amplifiers individually connected to the plurality of data bus lines and configured for detecting memory data stored in corresponding memory cells based on values of currents that are generated in the individual data bus lines in accordance with the memory data.Type: GrantFiled: October 10, 2008Date of Patent: November 1, 2011Assignee: Fujitsu Semiconductor LimitedInventor: Osamu Iioka
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Patent number: 8045388Abstract: The present invention provides a semiconductor memory and a control method therefor, the semiconductor device including a first current-voltage conversion circuit (16) connected to a core cell (12) provided in a nonvolatile memory cell array (10), a second current-voltage conversion circuit (26) connected to a reference cell (22) through a reference cell data line (24), a sense amplifier (18) sensing an output from the first current-voltage conversion circuit and an output from the second current-voltage conversion circuit, a compare circuit (28) comparing a voltage level at the reference cell data line with a predefined voltage level, and a charging circuit (30) charging the reference cell data line, if the voltage level at the reference cell data line is lower than the predefined voltage level during pre-charging the reference cell data line. According to the present invention, the pre-charging period of the reference cell data line can be shortened, and the data read time can be shortened.Type: GrantFiled: June 18, 2010Date of Patent: October 25, 2011Assignee: Spansion LLCInventors: Akira Ogawa, Masaru Yano
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Patent number: 8045389Abstract: A dummy cell array is provided in a memory cell array, and an intermediate buffer is provided between input/output circuits, whereby control signals to the input/output circuits can be operated at high speed and with a high frequency while the area increasing effect is reduced even in a memory with a large bit width.Type: GrantFiled: November 18, 2010Date of Patent: October 25, 2011Assignee: Panasonic CorporationInventors: Hidenari Kanehara, Yasuhiro Agata, Norihiko Sumitani, Akira Masuo
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Patent number: 8045390Abstract: A system for operating a memory device includes a memory array having a number of memory cells and a set of dynamic reference cells coupled to the memory cells in word lines. Each of the dynamic reference provides the associated memory cells with a dynamic reference value for determining a status of at least one of the associated memory cells. The dynamic reference value is capable of reflecting a variation in a threshold value of at least one of the associated memory cells.Type: GrantFiled: March 21, 2008Date of Patent: October 25, 2011Assignee: Macronix International Co., Ltd.Inventors: Jongoh Kim, Yi-Jin Kwon, Cheng-Jye Liu
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Patent number: 8040746Abstract: A memory device for efficient word line, bit line and precharge tracking is provided. The memory device includes a memory array, one or more address decoders, a word line driver, a plurality of sense amplifiers, a reference word line column, a reference bit line column, and a control circuit. The control circuit generates a control signal to perform read and write operations on the memory device. The address decoder selects a bit line and a word line. The selected word line is activated by the word line driver. While the reference word line column is used for vertical tracking of the word line, the reference bit line column is used for vertical tracking of the bit line. The sense amplifiers are activated to read the bit line.Type: GrantFiled: June 22, 2009Date of Patent: October 18, 2011Assignee: Freescale Semiconductor, Inc.Inventors: Sanjeev Kumar Jain, Devesh Dwivedi
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Patent number: 8040744Abstract: Techniques for the management of spare blocks in re-programmable non-volatile memory system, such as a flash EEPROM system, are presented. In one set of techniques, for a memory partitioned into two sections (for example a binary section and a multi-state section), where blocks of one section are more prone to error, spare blocks can be transferred from the more error prone partition to the less error prone partition. In another set of techniques for a memory partitioned into two sections, blocks which fail in the more error prone partition are transferred to serve as spare blocks in the other partition. In a complementary set of techniques, a 1-bit time stamp is maintained for free blocks to determine whether the block has been written recently. Other techniques allow for spare blocks to be managed by way of a logical to physical conversion table by assigning them logical addresses that exceed the logical address space of which a host is aware.Type: GrantFiled: January 5, 2009Date of Patent: October 18, 2011Assignee: SanDisk Technologies Inc.Inventors: Sergey Anatolievich Gorobets, Alan David Bennett, Eugene Zilberman
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Publication number: 20110242921Abstract: Systems and methods are disclosed for providing selective threshold voltage characteristics via use of MOS transistors having differential threshold voltages. In one exemplary embodiment, there is provided a metal oxide semiconductor device comprising a substrate of semiconductor material having a source region, a drain region and a channel region therebetween, an insulating layer over the channel region, and a gate portion of the insulating layer. Moreover, with regard to the device, the shape of the insulating layer and/or the shape or implantation of a junction region are of varied dimension as between the gate-to-drain and gate-to-source junctions to provide differential threshold voltages between them.Type: ApplicationFiled: March 30, 2010Publication date: October 6, 2011Inventors: Hieu Van Tran, Samar Saha
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Patent number: 8031527Abstract: A semiconductor device includes a first reference cell used for programming or reading non-volatile memory cells, and an adjustment circuit adjusting a first reference level of the first reference cell when the first reference level is changed.Type: GrantFiled: August 30, 2010Date of Patent: October 4, 2011Assignee: Spansion, LLCInventor: Yoshinori Kasuta
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Publication number: 20110235391Abstract: A method of selecting a reference circuit for a write operation is disclosed. The method comprises selecting a reference circuit for a write operation based on an output of a row decode circuit and a column decode circuit. The reference circuit is programmed concurrently with a write operation of at least one of a plurality of memory cells in a memory array without requiring an external reference circuit write command.Type: ApplicationFiled: March 25, 2010Publication date: September 29, 2011Applicant: QUALCOMM IncorporatedInventors: Jung Pill Kim, Hari M. Rao, Xia Li
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Patent number: 8027206Abstract: A Spin Transfer Torque Magnetoresistive Random Access Memory (STT-MRAM) and associated read operations are disclosed. A bit cell includes a magnetic tunnel junction (MTJ) and a word line transistor, the bit cell being coupled to a bit line and a source line. A clamping circuit is coupled to the bit line and is configured to clamp the bit line voltage to a desired voltage level during a read operation of the STT-MRAM to prevent the bit line voltage from exceeding the desired voltage level. The desired voltage level is less than a write voltage threshold associated with a write operation of the STT-MRAM.Type: GrantFiled: January 30, 2009Date of Patent: September 27, 2011Assignee: QUALCOMM IncorporatedInventors: Sei Seung Yoon, Seung H. Kang
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Patent number: 8023352Abstract: In a 4F2 memory cell designed using an SGT as a vertical transistor, a bit line has a high resistance because it is comprised of a diffusion layer underneath a pillar-shaped silicon layer, which causes a problem of slowdown in memory operation speed. The present invention provides a semiconductor storage device comprising an SGT-based 4F2 memory cell, wherein a bit line-backing cell having the same structure as that of a memory cell is inserted into a memory cell array to allow a first bit line composed of a diffusion layer to be backed with a low-resistance second bit line through the bit line backing cell, so as to provide a substantially low-resistance bit line, while suppressing an increase in area of the memory cell array.Type: GrantFiled: February 9, 2010Date of Patent: September 20, 2011Assignee: Unisantis Electronics (JAPAN) Ltd.Inventors: Fujio Masuoka, Shintaro Arai
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Patent number: 8023311Abstract: A Resistance based Random Access Memory (ReRAM) can include a sense amplifier circuit that includes a first input coupled to a bit line of a reference cell in a first block of the ReRAM responsive to a read operation to a second block.Type: GrantFiled: January 23, 2009Date of Patent: September 20, 2011Assignee: Samsung Electronics Co., Ltd.Inventors: Hyun-Jo Kim, Kyung-Tae Nam, In-Gyu Baek, Se-Chung Oh, Jang-Eun Lee, Jun-Ho Jeong
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Patent number: 8014202Abstract: In a non-volatile semiconductor memory device, variations in voltage applied to a bit line when an erase voltage applying step is repeatedly executed are suppressed, thereby reducing variations in Vt after erasure. A memory array includes memory cells arranged in an array, a plurality of word lines, and a plurality of bit lines and main bit lines. The memory array also includes a usable region which can store data and an isolation region which cannot store data. Each bit line provided in the usable region is connected via a select transistor to the corresponding main bit line. At least one main bit line is connected not only to a bit line of the usable region, but also to a bit line of the isolation region via a select transistor.Type: GrantFiled: June 23, 2009Date of Patent: September 6, 2011Assignee: Panasonic CorporationInventors: Masayoshi Nakayama, Kazuyuki Kouno, Reiji Mochida, Hoshihide Haruyama
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Patent number: 8014221Abstract: A semiconductor memory device includes a memory cell array which includes a plurality of unit memory cells, where each of the unit memory cells comprises complementary first and second floating body transistor capacitor-less memory cells. A logic value written into and read from each unit memory cell is defined by a difference in threshold voltage states of the first and second floating body transistor capacitorless memory cells.Type: GrantFiled: October 12, 2006Date of Patent: September 6, 2011Assignee: Samsung Electronics Co., Ltd.Inventor: Yeong-Taek Lee
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Publication number: 20110211410Abstract: A semiconductor memory device having an open bit line structure includes a normal memory cell block, a reference memory cell block, and a sense amplifier. The normal memory cell block includes a plurality of normal memory cells and a driving bit line connected to the normal memory cells. The reference memory cell block includes a reference bit line connected to a reference cell capacitor. The sense amplifier is configured to sense and amplify voltage levels of the driving bit line and the reference bit line.Type: ApplicationFiled: April 2, 2010Publication date: September 1, 2011Inventor: Seung-Lo KIM
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Publication number: 20110211383Abstract: An integrated circuit comprises a memory array and a bias circuit. The memory array comprises a plurality of memory cells arranged in a grid of rows and columns. A first conductor is coupled to a power supply voltage terminal of each of the plurality of memory cells. A second conductor is coupled to receive a power supply voltage. The memory array also includes a plurality of dummy cells. A transistor of one or more of the plurality of dummy cells has a first current electrode coupled to the first conductor, a second current electrode coupled to the second conductor, and a control electrode. The bias circuit is coupled to the control electrode of the transistor.Type: ApplicationFiled: February 26, 2010Publication date: September 1, 2011Inventor: Andrew C. Russell
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Patent number: 8009488Abstract: A semiconductor memory device includes a plurality of memory cell array blocks connected to word lines, source lines, and bit lines, each memory cell array including memory cells each having a transistor with a floating body, a reference voltage generator configured to have a reference memory cell and generate a reference voltage for bit line sensing corresponding to a current flowing into a reference memory cell during a data read operation, first and second prechargers configured to precharge a bit line connected to non-selected memory cells to the reference voltage in response to first and second precharge control signals during the data read operation, and a sense amplifier configured to sense and amplify a voltage difference between a bit line connected to the selected memory cells and a bit line connected to the non-selected memory cells during the data read operation.Type: GrantFiled: April 1, 2009Date of Patent: August 30, 2011Assignee: Samsung Electronics Co., Ltd.Inventors: Duk-Ha Park, Ki-Whan Song
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Patent number: 8004880Abstract: Systems, circuits and methods for reducing read disturbances in Spin Transfer Torque Magnetoresistive Random Access Memory (STT-MRAM) are disclosed. A resistive element can be used during the read operation to control the read current and control read disturbances. An isolation element can be used to isolate the resistive element from the circuit during write operations.Type: GrantFiled: June 29, 2007Date of Patent: August 23, 2011Assignee: QUALCOMM IncorporatedInventors: Sei Seung Yoon, Seung H Kang, Medi Hamidi Sani
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Publication number: 20110199812Abstract: A nonvolatile semiconductor memory device includes: a memory element in which a rate of charge discharge between two electrodes of the memory element differs according to a logical value of stored information; cell wiring connected to one electrode of the memory element; a sense amplifier having a sense node connected to the cell wiring, the sense amplifier reading the logical value of the information by comparing a potential of the sense node with a reference potential; and a readout control circuit capable of switching between a dynamic sense operation performing readout by precharging the cell wiring and discharging or charging the cell wiring via the memory element and a static sense operation performing readout in a state of a current load being connected to the sense node.Type: ApplicationFiled: January 20, 2011Publication date: August 18, 2011Applicant: Sony CorporationInventors: Makoto Kitagawa, Tsunenori Shiimoto, Tomohito Tsushima
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Patent number: 8000133Abstract: A tunnel magnetic resistive element forming a magnetic memory cell includes a fixed magnetic layer having a fixed magnetic field of a fixed direction, a free magnetic layer magnetized by an applied magnetic field, and a tunnel barrier that is an insulator film provided between the fixed and free magnetic layers in a tunnel junction region. In the free magnetic layer, a region corresponding to an easy axis region having characteristics desirable as a memory cell is used as the tunnel junction region. A hard axis region having characteristics undesirable as a memory cell is not used as a portion of the tunnel magnetic resistive element.Type: GrantFiled: April 6, 2010Date of Patent: August 16, 2011Assignee: Renesas Electronics CorporationInventor: Hideto Hidaka