Patents by Inventor Yuichiro Ishii
Yuichiro Ishii has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20190198074Abstract: A semiconductor device includes: memory cells, first word lined arranged for first ports and each arranging corresponding to respective rows of the memory cells; second word lines arranged for second ports and each arranged corresponding to respective rows of the memory cells, first dummy word lines each provided above the respective first word lines, second dummy word lines each provided above the respective second word lines, a word line driver driving the first and second word lines, and a dummy word line driver driving, in an opposite phase, the second dummy word line for the adjacent second word line according to driving of the first word line from among the first and second word lines, or the first dummy word line for the adjacent first word line according to driving of the second word line from among the first and second word lines.Type: ApplicationFiled: November 15, 2018Publication date: June 27, 2019Inventor: Yuichiro ISHII
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Publication number: 20190189197Abstract: Provided is a semiconductor memory device having a low power consumption write assist circuit. The semiconductor memory device includes multiple word lines, multiple bit line pairs, multiple memory cells, multiple auxiliary line pairs, a write driver circuit, a write assist circuit, and a select circuit. The memory cells are coupled to the word lines and the bit line pairs in such a manner that one memory cell is coupled to one word line and one bit line pair. The auxiliary line pairs run parallel to the bit line pairs in such a manner that one auxiliary line pair runs parallel to one bit line pair. The select circuit couples, to the write driver circuit, one bit line pair selected from the bit line pairs in accordance with a select signal, and couples, to the write assist circuit, an associated auxiliary line pair running parallel to the selected bit line pair.Type: ApplicationFiled: October 31, 2018Publication date: June 20, 2019Inventors: Koji NII, Yuichiro ISHII, Yohei SAWADA, Makoto YABUUCHI
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Patent number: 10325650Abstract: A semiconductor storage device includes an SRAM memory cell composed of a drive transistor, a transfer transistor and a load transistor, an I/O circuit that is connected to bit lines connected to the memory cell, and an operating mode control circuit that switches an operating mode of the I/O circuit between a resume standby mode and a normal operation mode, wherein the I/O circuit includes a write driver that writes data to bit lines, a sense amplifier that reads data from the bit lines, a first switch inserted between the bit lines and the write driver, a second switch inserted between the bit lines and the sense amplifier, a precharge circuit that precharges the bit lines, and a control circuit that controls the first and second switches and the precharge circuit according to a signal from the operating mode control circuit.Type: GrantFiled: August 7, 2018Date of Patent: June 18, 2019Assignee: RENESAS ELECTRONICS CORPORATIONInventor: Yuichiro Ishii
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Publication number: 20190172524Abstract: A semiconductor device includes a first mode and a second mode different from the first mode, includes a memory circuit including a first switch, a memory array, and a peripheral circuit. A first power source line is electrically coupled with an I/O circuit of the peripheral circuit and is supplied with a first voltage in the first mode. A second power source line is electrically coupled with a memory cell of the memory array, and supplied with a second voltage lower than the first voltage in the second mode.Type: ApplicationFiled: February 11, 2019Publication date: June 6, 2019Inventors: Yuichiro ISHII, Atsushi MIYANISHI, Kazumasa YANAGISAWA
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Publication number: 20190122703Abstract: A semiconductor memory device including a pair of first bit lines extended in a first direction, a pair of second bit lines extended in the first direction, a first word line extended in a second direction crossing the first direction, a second word line extended in the second direction, a memory cell surrounded by the first bit line, the second bit line, the first word line, and the second word line, and including a drive transistor, a first transfer transistor coupled with one of the pair of first bit lines, and having a gate coupled with the first word line, a second transfer transistor coupled with one of the pair of second bit lines, and having a gate coupled with the second word line, and a load transistor, a write drive circuit that transfers data to the memory cell.Type: ApplicationFiled: December 21, 2018Publication date: April 25, 2019Inventors: Shinji Tanaka, Yuichiro Ishii, Masaki Tsukude, Yoshikazu Saito
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Publication number: 20190108876Abstract: A semiconductor device includes a latch circuit receiving a first signal, generated in synchronization with a clock signal, from a pulse generation circuit, and generating a second signal; a first delay circuit receiving the second signal from the latch circuit, and generating a third signal by delaying the second signal; a second delay circuit receiving the third signal from the first delay circuit, and generating a fourth signal by delaying the third signal; and a logic circuit receiving the second and fourth signals from the latch and second delay circuits, respectively, and generating a word line control signal based on one of the second signal and the fourth signal. The latch circuit generates the second signal of a first level based on the first signal, and generates the second signal of a second level, which is different from the first level, based on the third signal.Type: ApplicationFiled: December 10, 2018Publication date: April 11, 2019Inventors: Yuichiro ISHII, Markoto Yabuuchi, Masao Morimoto
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Patent number: 10255970Abstract: An assist driver is coupled to an end of a word line to which a word line driver is not coupled, and couples the other end of the word line to a first power source, in accordance with a voltage of the other end of the word line.Type: GrantFiled: June 20, 2017Date of Patent: April 9, 2019Assignee: Renesas Electronics CorporationInventor: Yuichiro Ishii
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Patent number: 10224096Abstract: A semiconductor device includes: a first power source line for supplying a first voltage; a second power source line for supplying a second voltage; a memory circuit coupled with the first and second power source lines; a first switch which electrically coupling the first power source line with the second power source line and electrically decoupling the first power source line from the second power source line, in response to a control signal; a second switch which electrically coupling the first power source line with the second power source line and electrically decoupling the first power source line from the second power source line, in response to the control signal, wherein a memory circuit includes a memory cell array and a peripheral circuit, wherein a memory cell array includes a plurality of memory cells, the memory cells coupled with the second power source line.Type: GrantFiled: March 14, 2018Date of Patent: March 5, 2019Assignee: RENESAS ELECTRONICS CORPORATIONInventors: Yuichiro Ishii, Atsushi Miyanishi, Kazumasa Yanagisawa
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Publication number: 20190035456Abstract: An assist driver is coupled to an end of a word line to which a word line driver is not coupled, and couples the other end of the word line to a first power source, in accordance with a voltage of the other end of the word line.Type: ApplicationFiled: September 28, 2018Publication date: January 31, 2019Inventor: Yuichiro ISHII
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Publication number: 20190034260Abstract: The present invention provides a semiconductor memory device that can perform failure detection of an address decoder by a simple method with a low area overhead. The semiconductor memory device includes: a first memory array having a plurality of first memory cells arrange in matrix; a plurality of word lines provided corresponding to each of the memory cell rows; an address decoder for selecting a word line from the word lines based on the input address information; a second memory array that is provided adjacent to the first memory array in the column direction, having a plurality of second memory cells able to read address information used in the selection of the previously stored word line, according to the selection of the word line extended to the second memory array; and a comparison circuit for comparing the input address information with the address information read from the second memory array.Type: ApplicationFiled: October 4, 2018Publication date: January 31, 2019Inventors: Yuichiro ISHII, Atsushi MIYANISHI, Yoshikazu SAITO
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Publication number: 20190027212Abstract: A semiconductor device includes a SRAM (Static Random Access Memory) circuit. The SRAM circuit includes a static memory cell, a word line coupled with the static memory cell, a pair of bit lines coupled with the static memory cell, a first interconnection coupled with the static memory cell, and supplying a first potential, a second interconnection coupled with the static memory cell, and supplying a second potential lower than the first potential, a first potential control circuit controlling a potential of the second interconnection, and a second potential control circuit controlling a potential of the first interconnection. The SRAM circuit includes, as an operation mode a first operation mode for reading data from the SRAM circuit, or for writing data into the SRAM circuit, and a second operation mode for reducing power consumption than the first operation mode.Type: ApplicationFiled: September 27, 2018Publication date: January 24, 2019Inventors: Yohei SAWADA, Makoto YABUUCHI, Yuichiro ISHII
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Patent number: 10170161Abstract: A test method for a semiconductor memory device having a plurality of memory cells arranged in a matrix form, the test method including writing first data into a plurality of memory cells, while a plurality of word lines disposed in the columns of the memory cells are deselected, driving the low-potential side bit line of a bit line pair in the selected column, which is among a plurality of bit line pairs disposed in the columns of the memory cells, to a negative voltage level in accordance with second data complementary to the first data, and reading the data written into the memory cells.Type: GrantFiled: October 12, 2017Date of Patent: January 1, 2019Assignee: RENESAS ELECTRONICS CORPORATIONInventors: Shinji Tanaka, Yuichiro Ishii, Masaki Tsukude, Yoshikazu Saito
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Publication number: 20180366184Abstract: A semiconductor storage device includes a plurality of memory cells arranged in a matrix, a word line provided corresponding to a memory cell row, a dummy word line formed in a metal interconnection layer adjacent to a metal interconnection layer in which the word line is formed, a word driver circuit configured to drive the word line, and a dummy word driver circuit configured to increase voltage on the word line based on interline capacitance between the word line and the dummy word line.Type: ApplicationFiled: November 14, 2016Publication date: December 20, 2018Inventors: Yuichiro ISHII, Shinji TANAKA
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Patent number: 10153037Abstract: A circuit includes a memory cell array which includes: a plurality of memory cells; a plurality of word lines coupled to the memory cells, respectively, and a plurality of bit lines coupled to the memory cells, an address control circuit which includes: a first latch circuit into which a first address signal is input and from which a first output signal is output; a selection circuit into which a second address signal and the first output signal are input and which selects the first output signal or the second address signal for outputting the first output signal or the second address signal as a second output signal; a second latch circuit into which the second output signal is input and from which a third output signal is output; a decode circuit which decodes the third output signal and outputs a fourth output signal; and a word line drive circuit.Type: GrantFiled: January 31, 2018Date of Patent: December 11, 2018Assignee: RENESAS ELECTRONICS CORPORATIONInventors: Yuichiro Ishii, Makoto Yabuuchi, Masao Morimoto
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Publication number: 20180342292Abstract: A semiconductor storage device includes an SRAM memory cell composed of a drive transistor, a transfer transistor and a load transistor, an I/O circuit that is connected to bit lines connected to the memory cell, and an operating mode control circuit that switches an operating mode of the I/O circuit between a resume standby mode and a normal operation mode, wherein the I/O circuit includes a write driver that writes data to bit lines, a sense amplifier that reads data from the bit lines, a first switch inserted between the bit lines and the write driver, a second switch inserted between the bit lines and the sense amplifier, a precharge circuit that precharges the bit lines, and a control circuit that controls the first and second switches and the precharge circuit according to a signal from the operating mode control circuit.Type: ApplicationFiled: August 7, 2018Publication date: November 29, 2018Inventor: Yuichiro Ishii
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Patent number: 10120741Abstract: The present invention provides a semiconductor memory device that can perform failure detection of an address decoder by a simple method with a low area overhead. The semiconductor memory device includes: a first memory array having a plurality of first memory cells arrange in matrix; a plurality of word lines provided corresponding to each of the memory cell rows; an address decoder for selecting a word line from the word lines based on the input address information; a second memory array that is provided adjacent to the first memory array in the column direction, having a plurality of second memory cells able to read address information used in the selection of the previously stored word line, according to the selection of the word line extended to the second memory array; and a comparison circuit for comparing the input address information with the address information read from the second memory array.Type: GrantFiled: September 20, 2017Date of Patent: November 6, 2018Assignee: RENESAS ELECTRONICS CORPORATIONInventors: Yuichiro Ishii, Atsushi Miyanishi, Yoshikazu Saito
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Publication number: 20180301184Abstract: A memory circuit includes: a control circuit generating first and second start signals within a single signal cycle of an input clock signal; an address control circuit coupled to a plurality of address ports for receiving a plurality of address signals and activating one of word lines corresponding to one of the address signals based on the first or second start signals; and a data input/output circuit for writing or reading data by selecting one of memory cells coupled to the activated word line. The control circuit includes: a start signal generation unit that generates the first start signal in response to a first pulse signal and the second start signal in response to a second pulse signal, and a pulse signal generation unit that generates the first pulse signal in response to the input clock signal and the second signal in response to the first start signal.Type: ApplicationFiled: June 20, 2018Publication date: October 18, 2018Inventor: Yuichiro ISHII
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Patent number: 10102899Abstract: A semiconductor device includes a SRAM circuit. The SRAM circuit includes: a memory array having a plurality of memory cells arranged in a matrix; a ground interconnection commonly connected to each of the memory cells; and a first potential control circuit for controlling a potential of the ground interconnection depending on an operation mode. The first potential control circuit includes a first NMOS transistor and a first PMOS transistor connected in parallel to each other between a ground node providing a ground potential and the ground interconnection.Type: GrantFiled: March 31, 2015Date of Patent: October 16, 2018Assignee: RENESAS ELECTRONICS CORPORATIONInventors: Yohei Sawada, Makoto Yabuuchi, Yuichiro Ishii
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Patent number: 10068641Abstract: A semiconductor storage device includes an SRAM memory cell composed of a drive transistor, a transfer transistor and a load transistor, an I/O circuit that is connected to bit lines connected to the memory cell, and an operating mode control circuit that switches an operating mode of the I/O circuit between a resume standby mode and a normal operation mode, wherein the I/O circuit includes a write driver that writes data to bit lines, a sense amplifier that reads data from the bit lines, a first switch inserted between the bit lines and the write driver, a second switch inserted between the bit lines and the sense amplifier, a precharge circuit that precharges the bit lines, and a control circuit that controls the first and second switches and the precharge circuit according to a signal from the operating mode control circuit.Type: GrantFiled: February 12, 2018Date of Patent: September 4, 2018Assignee: RENESAS ELECTRONICS CORPORATIONInventor: Yuichiro Ishii
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Publication number: 20180204612Abstract: A semiconductor device includes: a first power source line for supplying a first voltage; a second power source line for supplying a second voltage; a memory circuit coupled with the first and second power source lines; a first switch which electrically coupling the first power source line with the second power source line and electrically decoupling the first power source line from the second power source line, in response to a control signal; a second switch which electrically coupling the first power source line with the second power source line and electrically decoupling the first power source line from the second power source line, in response to the control signal, wherein a memory circuit includes a memory cell array and a peripheral circuit, wherein a memory cell array includes a plurality of memory cells, the memory cells coupled with the second power source line.Type: ApplicationFiled: March 14, 2018Publication date: July 19, 2018Inventors: Yuichiro Ishii, Atsushi Miyanishi, Kazumasa Yanagisawa