Patents by Inventor Shigeki Ohbayashi
Shigeki Ohbayashi 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).
-
Publication number: 20090034317Abstract: A semiconductor storage device includes a memory cell array, a plurality of word lines, a plurality of bit lines, a first gate wiring element 3a, 3b, a second gate wiring element 3c, 3d, a first connector 5a, 5b, and a second connector 5c, 5d. Each memory cell 10 has first and second sets having a driver transistor 11, a load transistor 12, and an access transistor 13. The word lines are arranged in parallel to each other along a first direction. The bit lines are arranged in parallel to each other along a second direction perpendicular to the first direction. The first gate wiring element comprises a gate electrode of the first driver transistor and the first load transistor, and has a rectangular shape having straight line on opposite sides. The second gate wiring element comprises a gate electrode of the access transistor and has a rectangular shape having straight line on opposite sides.Type: ApplicationFiled: September 24, 2008Publication date: February 5, 2009Applicant: RENESAS TECHNOLOGY CORP.Inventors: Hidemoto TOMITA, Shigeki Ohbayashi, Yoshiyuki Ishigaki
-
Publication number: 20070177416Abstract: A semiconductor storage device includes a memory cell array, a plurality of word lines, a plurality of bit lines, a first gate wiring element 3a, 3b, a second gate wiring element 3c, 3d, a first connector 5a, 5b, and a second connector 5c, 5d. Each memory cell 10 has first and second sets having a driver transistor 11, a load transistor 12, and an access transistor 13. The word lines are arranged in parallel to each other along a first direction. The bit lines are arranged in parallel to each other along a second direction perpendicular to the first direction. The first gate wiring element comprises a gate electrode of the first driver transistor and the first load transistor, and has a rectangular shape having straight line on opposite sides. The second gate wiring element comprises a gate electrode of the access transistor and has a rectangular shape having straight line on opposite sides.Type: ApplicationFiled: March 23, 2007Publication date: August 2, 2007Applicant: RENESAS TECHNOLOGY CORP.Inventors: Hidemoto Tomita, Shigeki Ohbayashi, Yoshiyuki Ishigaki
-
Publication number: 20070030741Abstract: A level shift element adjusting a voltage level at the time of selection of a word line according to fluctuations in threshold voltage of a memory cell transistor is arranged for each word line. This level shift element lowers a driver power supply voltage, and transmits the level-shifted voltage onto a selected word line. The level shift element can be replaced with a pull-down element for pulling down the word line voltage according to the threshold voltage level of the memory cell transistor. In either case, the selected word line voltage level can be adjusted according to the fluctuations in threshold voltage of the memory cell transistor without using another power supply system. Thus, the power supply circuitry is not complicated, and it is possible to achieve a semiconductor memory device that can stably read and write data even with a low power supply voltage.Type: ApplicationFiled: July 25, 2006Publication date: February 8, 2007Applicant: Renesas Technology Corp.Inventors: Koji Nii, Shigeki Ohbayashi, Yasumasa Tsukamoto, Makoto Yabuuchi
-
Publication number: 20060285400Abstract: A supply instruction signal attains the H-level before data is written into a plurality of memory cells. A P-channel MOS transistor is arranged between a power supply node and an input node. The P-channel MOS transistor is turned off to open the input node according to the supply instruction signal. In this case, a write driver discharges electric charges accumulated on the input node and electric charges accumulated on a bit line pair. However, a through-current does not flow from the power supply node to a ground node so that flow of the through-current to a CMOS inverter circuit forming each memory cell can be prevented. Accordingly, such a static semiconductor memory device can be provided that can prevent the flow of the through-current to the CMOS inverter circuit forming each memory cell when simultaneously writing data into the plurality of memory cells.Type: ApplicationFiled: June 13, 2006Publication date: December 21, 2006Inventor: Shigeki Ohbayashi
-
Patent number: 7076705Abstract: Current consumption of an input unit with respect to a bonding option pad is reduced, and erroneous operation of a circuit connected to this bonding option pad is prevented. A boundary scan test circuit is selectively set to an operable or disabled state by a control gate according to a signal from a function set circuit that sets the operation mode according to a potential of a bonding pad. By particularly controlling the operable and disabled state of an input circuit located at the first stage of the test circuit, power consumption can be reduced and erroneous operation while the test circuit is disabled is prevented.Type: GrantFiled: October 5, 2005Date of Patent: July 11, 2006Assignee: Renesas Technology Corp.Inventor: Shigeki Ohbayashi
-
Publication number: 20060119395Abstract: A CMOS LSI includes an inverter including first and second MOS transistors, a relatively long metal interconnection connected to an input node of the inverter, first and second diodes releasing charges born by the metal interconnection during a plasma process to first and second wells, and first and second MOS transistors maintaining a voltage between the first and second wells at a level not higher than a prescribed voltage. Therefore, even when an antenna ratio is high, a gate oxide film in the first and second MOS transistors is not damaged during the plasma process.Type: ApplicationFiled: December 1, 2005Publication date: June 8, 2006Inventors: Shigeki Ohbayashi, Hiroaki Suzuki, Koichiro Ishibashi, Hiroshi Makino
-
Patent number: 7038925Abstract: Above a memory block including horizontal memory cells in 8 rows by 256 columns, a total of eight lines, a global word line, a bit line load power supply line, a local data input/output line pair, a bit line signal input/output line pair, a memory cell power supply line and a global column selecting line are, arranged at equal intervals. Since provision of one line is enough per one memory cell row, an SRAM having a T-type bit line structure can be realized with ease using horizontal memory cells to enable reduction of a layout area and speed-up of an operation rate.Type: GrantFiled: April 10, 2001Date of Patent: May 2, 2006Assignee: Renesas Technology Corp.Inventor: Shigeki Ohbayashi
-
Publication number: 20060059396Abstract: Current consumption of an input unit with respect to a bonding option pad is reduced, and erroneous operation of a circuit connected to this bonding option pad is prevented. A boundary scan test circuit is selectively set to an operable or disabled state by a control gate according to a signal from a function set circuit that sets the operation mode according to a potential of a bonding pad. By particularly controlling the operable and disabled state of an input circuit located at the first stage of the test circuit, power consumption can be reduced and erroneous operation while the test circuit is disabled is prevented.Type: ApplicationFiled: October 5, 2005Publication date: March 16, 2006Applicant: Renesas Technology Corp.Inventor: Shigeki Ohbayashi
-
Patent number: 6976200Abstract: Current consumption of an input unit with respect to a bonding option pad is reduced, and erroneous operation of a circuit connected to this bonding option pad is prevented. A boundary scan test circuit is selectively set to an operable or disabled state by a control gate according to a signal from a function set circuit that sets the operation mode according to a potential of a bonding pad. By particularly controlling the operable and disabled state of an input circuit located at the first stage of the test circuit, power consumption can be reduced and erroneous operation while the test circuit is disabled is prevented.Type: GrantFiled: November 20, 1998Date of Patent: December 13, 2005Assignee: Renesas Technology Corp.Inventor: Shigeki Ohbayashi
-
Patent number: 6891743Abstract: A CMOS-SRAM has a plurality of full CMOS type memory cells (1) and a capacity plate (2). The memory cells (1) are two-dimensionally arranged in the row direction and in the column direction. The capacity plate 2 adds an additional capacity to nodes ND1 and ND2 for storing data in order to reduce soft errors. The capacity plate (2) is common with the plurality of memory cells (1). The capacity plates (2) are separated by every column, that is in the row direction. The capacity plate (2) is connected to a power voltage line VDD so as to simplify the voltage supplying system. When a stand-by failure occurs in the memory cell (1) of a certain column, the memory cell (1) is replaced with a redundant memory cell.Type: GrantFiled: July 16, 2002Date of Patent: May 10, 2005Assignee: Renesas Technology Corp.Inventors: Shigeki Ohbayashi, Yoshiyuki Ishigaki, Takahiro Yokoyama
-
Publication number: 20050083756Abstract: A semiconductor storage device includes a memory cell array, a plurality of word lines, a plurality of bit lines, a first gate wiring element 3a, 3b, a second gate wiring element 3c, 3d, a first connector 5a, 5b, and a second connector 5c, 5d. Each memory cell 10 has first and second sets having a driver transistor 11, a load transistor 12, and an access transistor 13. The word lines are arranged in parallel to each other along a first direction. The bit lines are arranged in parallel to each other along a second direction perpendicular to the first direction. The first gate wiring element comprises a gate electrode of the first driver transistor and the first load transistor, and has a rectangular shape having straight line on opposite sides. The second gate wiring element comprises a gate electrode of the access transistor and has a rectangular shape having straight line on opposite sides.Type: ApplicationFiled: October 25, 2004Publication date: April 21, 2005Applicant: Mitsubishi Denki Kabushiki KaishaInventors: Hidemoto Tomita, Shigeki Ohbayashi, Yoshiyuki Ishigaki
-
Patent number: 6812574Abstract: A semiconductor storage device includes a memory cell array, a plurality of word lines, a plurality of bit lines, a first gate wiring element 3a, 3b, a second gate wiring element 3c, 3d, a first connector 5a, 5b, and a second connector 5c, 5d. Each memory cell 10 has first and second sets having a driver transistor 11, a load transistor 12, and an access transistor 13. The word lines are arranged in parallel to each other along a first direction. The bit lines are arranged in parallel to each other along a second direction perpendicular to the first direction. The first gate wiring element comprises a gate electrode of the first driver transistor and the first load transistor, and has a rectangular shape having straight line on opposite sides. The second gate wiring element comprises a gate electrode of the access transistor and has a rectangular shape having straight line on opposite sides.Type: GrantFiled: July 9, 2002Date of Patent: November 2, 2004Assignee: Renesas Technology Corp.Inventors: Hidemoto Tomita, Shigeki Ohbayashi, Yoshiyuki Ishigaki
-
Patent number: 6781869Abstract: A semiconductor memory having: a full CMOS-type of memory cell (10) including an n-type bulk access transistor (7, 8), an n-type bulk driver transistor (5, 6) and a p-type bulk load transistor (3, 4) by twos, and a charge capacitance adding charge capacitor element (9) connected to cell nodes (N1, N2) in order to secure a soft error resistance. In the semiconductor memory, an insulating film (14) and a conductive film (15) are directly formed on each upper side of first and second cell nodes (N1, N2) for constituting a charge capacitor element (9) for adding a charge capacitance. The insulating film (14) is held between the cell node (N1, N2) and the conductive film (15), covering both first and second cell nodes (N1, N2) in common.Type: GrantFiled: December 26, 2002Date of Patent: August 24, 2004Assignee: Renesas Technology Corp.Inventors: Shigeki Ohbayashi, Yoshiyuki Ishigaki, Takahiro Yokoyama
-
Patent number: 6741510Abstract: A control circuit generates burn-in test signals and a signal on the basis of an address for causing transition of a semiconductor memory device to a burn-in test mode to output the signals to a predecoder. The predecoder outputs signals for selecting even-numbered word lines and signals for causing odd-numbered word lines to be in a non-selected state on the basis of the burn-in test signals at H level and further outputs signals for causing even-numbered word lines to be in a non-selected state and signals for selecting odd-numbered word lines on the basis of the burn-in test signals at H level. As a result, stresses can be effectively applied by the burn-in test.Type: GrantFiled: August 20, 2002Date of Patent: May 25, 2004Assignee: Renesas Technology Corp.Inventors: Shigeki Ohbayashi, Yoji Kashihara, Takahiro Yokoyama
-
Patent number: 6714478Abstract: A local decoder controlling activation of each word line includes a first transistor connected between first and second nodes, a second transistor connected between a power-supply voltage and the first node, and an inverter driving a word line with the power-supply voltage or a ground voltage in accordance with the voltage of the first node. When a corresponding word line is activated, the second node is set at the ground voltage while the first transistor is turned on. In a burn-in test, a burn-in control circuit forcibly turns off the second transistor in a local decoder corresponding to a word line to be activated.Type: GrantFiled: August 7, 2002Date of Patent: March 30, 2004Assignee: Renesas Technology Corp.Inventors: Hidemoto Tomita, Motomu Ukita, Shigeki Ohbayashi, Yoji Kashihara
-
Patent number: 6710634Abstract: In a power on reset (POR) circuit, when power is turned on, an output signal of an inverter attains an H level and an N channel MOS transistor is rendered conductive. The potential of an input node of the inverter becomes a potential of a power supply voltage divided by a conductive resistance value R1 of a P channel MOS transistor and a conductive resistance value R2 of an N channel MOS transistor. Assuming that the threshold voltage of the inverter is 0.8 V and R1:R2=2:3, then the power supply voltage Vres at the time when signal POR# inverts its level becomes 1.33 V. Thus, this POR circuit can reliably be utilized even in a product designed to operate with 1.5 V incorporating a MOS transistor having a threshold voltage of 0.8 V.Type: GrantFiled: April 4, 2003Date of Patent: March 23, 2004Assignee: Renesas Technology Corp.Inventors: Shigeki Ohbayashi, Tadayuki Shimizu
-
Patent number: 6711070Abstract: A comparator of a synchronous SRAM includes: n+1 EX-OR gates for detecting whether or not n+1 signals included in an address signal inputted in a cycle and n+1 signals included in an address signal inputted in the next cycle coincide with each other; and wired OR gates receiving output signals of the n+1 EX-OR gates. Accordingly, a detecting speed is faster than in a prior art practice where an OR gate is constituted of NOR gates and NAND gates at multiple stages.Type: GrantFiled: August 19, 2002Date of Patent: March 23, 2004Assignee: Renesas Technology Corp.Inventors: Yoji Kashihara, Shigeki Ohbayashi
-
Patent number: 6704238Abstract: During a burn-in test, each read selection gate, each write selection gate, a write control circuit, and a sense amplifier circuit are activated, and a read data bus precharge and equalize circuit and a global read data bus precharge and equalize circuit are inactivated. As a result, a voltage difference applied between a global write data bus pair is transferred to each of a write data bus pair, a bit line pair, a read data bus pair, and a global read data bus pair without involving a mode switching.Type: GrantFiled: August 20, 2002Date of Patent: March 9, 2004Assignee: Renesas Technology Corp.Inventors: Takashi Izutsu, Shigeki Ohbayashi, Yoji Kashihara
-
Publication number: 20030201807Abstract: In a power on reset (POR) circuit, when power is turned on, an output signal of an inverter attains an H level and an N channel MOS transistor is rendered conductive. The potential of an input node of the inverter becomes a potential of a power supply voltage divided by a conductive resistance value R1 of a P channel MOS transistor and a conductive resistance value R2 of an N channel MOS transistor. Assuming that the threshold voltage of the inverter is 0.8 V and R1:R2=2:3, then the power supply voltage Vres at the time when signal POR# inverts its level becomes 1.33 V. Thus, this POR circuit can reliably be utilized even in a product designed to operate with 1.5 V incorporating a MOS transistor having a threshold voltage of 0.8 V.Type: ApplicationFiled: April 4, 2003Publication date: October 30, 2003Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Shigeki Ohbayashi, Tadayuki Shimizu
-
Publication number: 20030161204Abstract: A control circuit generates burn-in test signals and a signal on the basis of an address for causing transition of a semiconductor memory device to a burn-in test mode to output the signals to a predecoder. The predecoder outputs signals for selecting even-numbered word lines and signals for causing odd-numbered word lines to be in a non-selected state on the basis of the burn-in test signals at H level and further outputs signals for causing even-numbered word lines to be in a non-selected state and signals for selecting odd-numbered word lines on the basis of the burn-in test signals at H level. As a result, stresses can be effectively applied by the burn-in test.Type: ApplicationFiled: August 20, 2002Publication date: August 28, 2003Applicant: Mitsubishi Denki Kabushiki KaishaInventors: Shigeki Ohbayashi, Yoji Kashihara, Takahiro Yokoyama