Patents by Inventor Shigetoshi Wakayama
Shigetoshi Wakayama 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).
-
Patent number: 8468481Abstract: A design support program executed by a computer includes operations of: locating at least one via hole for coupling target wiring in a first layer in circuit information to wiring in a second layer being different form the first layer; calculating an area of the target wiring based on a length and a width of the target wiring; setting a division condition based on the area and a number of the via hole; dividing the target wiring into divided wirings at a position other than a position where the via hole is provided based on the division condition; generating connection information indicating a connection relationship between the divided wirings and limitation information for coupling the divided wirings via a wiring in a third layer being different from the first layer; and outputting the connection information, the limitation information and circuit information obtained after dividing.Type: GrantFiled: July 23, 2010Date of Patent: June 18, 2013Assignee: Fujitsu Semiconductor LimitedInventors: Toshiharu Nozawa, Shigetoshi Wakayama, Mitsuaki Igeta
-
Patent number: 8065553Abstract: A semiconductor integrated circuit device has a command decoder for issuing a control command in accordance with a supplied control signal, a DRAM core, and a timing adjusting circuit for supplying the control command, set active for a predetermined period, as a DRAM control signal to the DRAM core. The timing adjusting circuit generates n different clocks that are respectively shifted in phase with respect to a supplied reference clock, and generates the DRAM control signal by setting the control command active in a prescribed operation cycle for only a period starting at a first predetermined clock pulse of a first clock of the n clocks and ending at a second predetermined clock pulse of a second clock of the n clocks. In this way, timing design with relatively high accuracy of adjustment can be done in a short period.Type: GrantFiled: January 23, 2009Date of Patent: November 22, 2011Assignee: Fujitsu LimitedInventors: Hirotaka Tamura, Hisakatsu Yamaguchi, Shigetoshi Wakayama, Kohtaroh Gotoh, Junji Ogawa
-
Publication number: 20110041113Abstract: A design support program executed by a computer includes operations of: locating at least one via hole for coupling target wiring in a first layer in circuit information to wiring in a second layer being different form the first layer; calculating an area of the target wiring based on a length and a width of the target wiring; setting a division condition based on the area and a number of the via hole; dividing the target wiring into divided wirings at a position other than a position where the via hole is provided based on the division condition; generating connection information indicating a connection relationship between the divided wirings and limitation information for coupling the divided wirings via a wiring in a third layer being different from the first layer; and outputting the connection information, the limitation information and circuit information obtained after dividing.Type: ApplicationFiled: July 23, 2010Publication date: February 17, 2011Applicant: FUJITSU SEMICONDUCTOR LIMITEDInventors: Toshiharu NOZAWA, Shigetoshi Wakayama, Mitsuaki Igeta
-
Patent number: 7642624Abstract: A multilayer interconnection structure of a semiconductor device includes a first guard ring extending continuously along a periphery of a substrate and a second guard ring extending continuously in the multilayer interconnection structure along the periphery so as to be encircled by the first guard ring and so as to encircle an interconnection pattern inside the multilayer interconnection structure, wherein the first and second guard rings are connected with each other mechanically and continuously by a bridging conductor pattern extending continuously in a band form along a region including the first and second guard rings when viewed in the direction perpendicular to the substrate.Type: GrantFiled: July 6, 2007Date of Patent: January 5, 2010Assignee: Fujitsu Microelectronics LimitedInventors: Shigetoshi Wakayama, Matsuaki Kai, Hiroyuki Kato, Masato Suga
-
Publication number: 20090195281Abstract: A semiconductor integrated circuit device has a command decoder for issuing a control command in accordance with a supplied control signal, a DRAM core, and a timing adjusting circuit for supplying the control command, set active for a predetermined period, as a DRAM control signal to the DRAM core. The timing adjusting circuit generates n different clocks that are respectively shifted in phase with respect to a supplied reference clock, and generates the DRAM control signal by setting the control command active in a prescribed operation cycle for only a period starting at a first predetermined clock pulse of a first clock of the n clocks and ending at a second predetermined clock pulse of a second clock of the n clocks. In this way, timing design with relatively high accuracy of adjustment can be done in a short period.Type: ApplicationFiled: January 23, 2009Publication date: August 6, 2009Applicant: FUJITSU LIMITEDInventors: Hirotaka Tamura, Hisakatsu Yamaguchi, Shigetoshi Wakayama, Kohtaroh Gotoh, Junji Ogawa
-
Patent number: 7496781Abstract: A semiconductor integrated circuit device has a command decoder for issuing a control command in accordance with a supplied control signal, a DRAM core, and a timing adjusting circuit for supplying the control command, set active for a predetermined period, as a DRAM control signal to the DRAM core. The timing adjusting circuit generates n different clocks that are respectively shifted in phase with respect to a supplied reference clock, and generates the DRAM control signal by setting the control command active in a prescribed operation cycle for only a period starting at a first predetermined clock pulse of a first clock of the n clocks and ending at a second predetermined clock pulse of a second clock of the n clocks. In this way, timing design with relatively high accuracy of adjustment can be done in a short period.Type: GrantFiled: October 24, 2002Date of Patent: February 24, 2009Assignee: Fujitsu, Ltd.Inventors: Hirotaka Tamura, Hisakatsu Yamaguchi, Shigetoshi Wakayama, Kohtaroh Gotoh, Junji Ogawa
-
Patent number: 7342434Abstract: A capacitor has a MOS gate structure in which a gate insulating film is held between a gate terminal and a ground terminal as a dielectric. A switch unit is connected between the gate terminal and a power supply. The ground terminal is connected to a ground. A switch control circuit that switches a state of the switch unit between a conductive state and a nonconductive state is provided. A predetermined voltage and a voltage of the gate terminal are input to a non-inverting input terminal and an inverting input terminal of the switch control circuit, respectively. The switch unit is conductive when the voltage of the gate terminal is higher than the predetermined voltage, and nonconductive when the voltage of the gate terminal is lower than the predetermined voltage.Type: GrantFiled: January 26, 2005Date of Patent: March 11, 2008Assignee: Fujitsu LimitedInventors: Shigetoshi Wakayama, Mutsuaki Kai
-
Publication number: 20070257371Abstract: A multilayer interconnection structure of a semiconductor device includes a first guard ring extending continuously along a periphery of a substrate and a second guard ring extending continuously in the multilayer interconnection structure along the periphery so as to be encircled by the first guard ring and so as to encircle an interconnection pattern inside the multilayer interconnection structure, wherein the first and second guard rings are connected with each other mechanically and continuously by a bridging conductor pattern extending continuously in a band form along a region including the first and second guard rings when viewed in the direction perpendicular to the substrate.Type: ApplicationFiled: July 6, 2007Publication date: November 8, 2007Applicant: FUJITSU LIMITEDInventors: Shigetoshi Wakayama, Mutsuaki Kai, Hiroyuki Kato, Masato Suga
-
Patent number: 7256474Abstract: A multilayer interconnection structure of a semiconductor device includes a first guard ring extending continuously along a periphery of a substrate and a second guard ring extending continuously in the multilayer interconnection structure along the periphery so as to be encircled by the first guard ring and so as to encircle an interconnection pattern inside the multilayer interconnection structure, wherein the first and second guard rings are connected with each other mechanically and continuously by a bridging conductor pattern extending continuously in a band form along a region including the first and second guard rings when viewed in the direction perpendicular to the substrate.Type: GrantFiled: February 13, 2004Date of Patent: August 14, 2007Assignee: Fujitsu LimitedInventors: Shigetoshi Wakayama, Mutsuaki Kai, Hiroyuki Kato, Masato Suga
-
Patent number: 7106108Abstract: An input circuit writes an expected value to one end of an evaluation wiring. A latch circuit latches a logic level of the other end of the evaluation wiring. A first switch circuit connects an output of the input circuit to the input of the latch circuit. A second switch circuit connects the output of the input circuit to the one end of the evaluation wiring. A third switch circuit connects the other end of the evaluation wiring to the input of the latch circuit. By turning on, off, and off the first to third switch circuits, respectively, the output of the input circuit is directly connected to only the input of the latch circuit. In this state, the input circuit writes an expected value, and a logic level is read from the latch circuit. Accordingly, failure of the evaluation wiring can be easily discriminated from other failure.Type: GrantFiled: June 18, 2004Date of Patent: September 12, 2006Assignee: Fujitsu LimitedInventors: Mitsuaki Igeta, Shigetoshi Wakayama, Seiji Endou
-
Patent number: 7096375Abstract: A circuit for data transfer includes a first buffer operating at a first clock frequency, a plurality of second buffers operating at a second clock frequency, and a selector circuit which receives data at the first clock frequency, and supplies the data to a selected one of the first buffer and the second buffers.Type: GrantFiled: November 19, 2002Date of Patent: August 22, 2006Assignee: Fujitsu LimitedInventors: Shigetoshi Wakayama, Hiroshi Okano, Yoshio Hirose
-
Publication number: 20060061409Abstract: A capacitor has a MOS gate structure in which a gate insulating film is held between a gate terminal and a ground terminal as a dielectric. A switch unit is connected between the gate terminal and a power supply. The ground terminal is connected to a ground. A switch control circuit that switches a state of the switch unit between a conductive state and a nonconductive state is provided. A predetermined voltage and a voltage of the gate terminal are input to a non-inverting input terminal and an inverting input terminal of the switch control circuit, respectively. The switch unit is conductive when the voltage of the gate terminal is higher than the predetermined voltage, and nonconductive when the voltage of the gate terminal is lower than the predetermined voltage.Type: ApplicationFiled: January 26, 2005Publication date: March 23, 2006Inventors: Shigetoshi Wakayama, Mutsuaki Kai
-
Publication number: 20050144546Abstract: An input circuit writes an expected value to one end of an evaluation wiring. A latch circuit latches a logic level of the other end of the evaluation wiring. A first switch circuit connects an output of the input circuit to the input of the latch circuit. A second switch circuit connects the output of the input circuit to the one end of the evaluation wiring. A third switch circuit connects the other end of the evaluation wiring to the input of the latch circuit. By turning on, off, and off the first to third switch circuits, respectively, the output of the input circuit is directly connected to only the input of the latch circuit. In this state, the input circuit writes an expected value, and a logic level is read from the latch circuit. Accordingly, failure of the evaluation wiring can be easily discriminated from other failure.Type: ApplicationFiled: June 18, 2004Publication date: June 30, 2005Inventors: Mitsuaki Igeta, Shigetoshi Wakayama, Seiji Endou
-
Publication number: 20040188843Abstract: A multilayer interconnection structure of a semiconductor device includes a first guard ring extending continuously along a periphery of a substrate and a second guard ring extending continuously in the multilayer interconnection structure along the periphery so as to be encircled by the first guard ring and so as to encircle an interconnection pattern inside the multilayer interconnection structure, wherein the first and second guard rings are connected with each other mechanically and continuously by a bridging conductor pattern extending continuously in a band form along a region including the first and second guard rings when viewed in the direction perpendicular to the substrate.Type: ApplicationFiled: February 13, 2004Publication date: September 30, 2004Applicant: FUJITSU LIMITEDInventors: Shigetoshi Wakayama, Mutsuaki Kai, Hiroyuki Kato, Masato Suga
-
Publication number: 20030112051Abstract: A circuit for data transfer includes a first buffer operating at a first clock frequency, a plurality of second buffers operating at a second clock frequency, and a selector circuit which receives data at the first clock frequency, and supplies the data to a selected one of the first buffer and the second buffers.Type: ApplicationFiled: November 19, 2002Publication date: June 19, 2003Inventors: Shigetoshi Wakayama, Hiroshi Okano, Yoshio Hirose
-
Patent number: 6493394Abstract: A signal transmission system has a response time of a signal transmission line which is set approximately equal to or longer than the length of a transmitted symbol. More specifically, terminal resistance is set larger than the characteristic impedance of the signal transmission line, driver output resistance is set to a large value, or a damping resistor is provided in series with the signal transmission line. With this configuration, signal power can be reduced drastically.Type: GrantFiled: February 19, 2002Date of Patent: December 10, 2002Assignee: Fujitsu LimitedInventors: Hirotaka Tamura, Miyoshi Saito, Kohtaroh Gotoh, Shigetoshi Wakayama, Junji Ogawa, Hisakatsu Araki, Tsz-shing Cheung
-
Patent number: 6484268Abstract: A semiconductor integrated circuit device has a command decoder for issuing a control command in accordance with a supplied control signal, a DRAM core, and a timing adjusting circuit for supplying the control command, set active for a predetermined period, as a DRAM control signal to the DRAM core. The timing adjusting circuit generates n different clocks that are respectively shifted in phase with respect to a supplied reference clock, and generates the DRAM control signal by setting the control command active in a prescribed operation cycle for only a period starting at a first predetermined clock pulse of a first clock of the n clocks and ending at a second predetermined clock pulse of a second clock of the n clocks. In this way, timing design with relatively high accuracy of adjustment can be done in a short period.Type: GrantFiled: February 28, 2001Date of Patent: November 19, 2002Assignee: Fujitsu LimitedInventors: Hirotaka Tamura, Hisakatsu Araki, Shigetoshi Wakayama, Kohtaroh Gotoh, Junji Ogawa
-
Publication number: 20020080883Abstract: A signal transmission system has a response time of a signal transmission line which is set approximately equal to or longer than the length of a transmitted symbol. More specifically, terminal resistance is set larger than the characteristic impedance of the signal transmission line, driver output resistance is set to a large value, or a damping resistor is provided in series with the signal transmission line. With this configuration, signal power can be reduced drastically.Type: ApplicationFiled: February 19, 2002Publication date: June 27, 2002Applicant: FUJITSU LIMITEDInventors: Hirotaka Tamura, Miyoshi Saito, Kohtaroh Gotoh, Shigetoshi Wakayama, Junji Ogawa, Hisakatsu Araki, Tsz-shing Cheung
-
Patent number: 6377638Abstract: A signal transmission system has a response time of a signal transmission line which is set approximately equal to or longer than the length of a transmitted symbol. More specifically, terminal resistance is set larger than the characteristic impedance of the signal transmission line, driver output resistance is set to a large value, or a damping resistor is provided in series with the signal transmission line. With this configuration, signal power can be reduced drastically.Type: GrantFiled: October 12, 2000Date of Patent: April 23, 2002Assignee: Fujitsu LimitedInventors: Hirotaka Tamura, Miyoshi Saito, Kohtaroh Gotoh, Shigetoshi Wakayama, Junji Ogawa, Hisakatsu Araki, Tsz-shing Cheung
-
Patent number: 6333883Abstract: A restoring circuit 24, provided for each of the memory blocks 191 and 192, having registers and a selector for selecting one of the present row address and the output of the registers, provides the output of the selector to a word decoder 26. The present row address is held in one of the registers. When amplification is started by a sense amplifier 15, transfer gates 10 and 11 connected between the bit lines BL1 and *BL1 and the sense amplifier 15 are turned off to decrease the load of the sense amplifier 15, the amplified signal is stored in a buffer memory cell circuit 18, and accessing is completed with omitting restoring to the memory cell 12. While the memory cell block 191 is not selected, the data held in the buffer memory cell circuit 18 is stored into the memory cell row addressed by the content of the selected register. The sense amplifier 15 has PMOS and NMOS sense amplifiers.Type: GrantFiled: January 25, 2001Date of Patent: December 25, 2001Assignee: Fujitsu LimitedInventors: Shigetoshi Wakayama, Kohtaroh Gotoh, Miyoshi Saito, Junji Ogawa