Patents by Inventor Shunichi Sukegawa

Shunichi Sukegawa 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: 6002162
    Abstract: Realizing a reduction of the layout surface area by rendering unnecessary the region used for well isolation. In this DRAM, a triple well construction is used, and all of the regions for the unit memory cell array MA, the word line driver bank WDB, the sense amplifier bank SAB, and the cross area CR are surrounded by a lower layer N-type deep (deep layer) well 12. A back bias VPP corresponding to the power supply voltage of the word line driver is applied to the N well 14, and a back bias VBB corresponding to the characteristics of the memory cell are applied to the P well 16. In the N well 14, in regard to the P-type MOS transistors of the sense amplifier that undergo the substrate bias effect due to the back bias VPP, the threshold voltage is set to a low value so as to cancel that bias effect.
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: December 14, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Yasushi Takahashi, Tsutomu Takahashi, Koji Arai, Shinji Bessho, Shunichi Sukegawa, Masayuki Hira
  • Patent number: 5970010
    Abstract: Controlling the timing for the overdrive of the sense amplifiers in response to the wiring length between the sense amplifiers and the power supply voltage supply nodes, and designing a reduction of the power consumption by preventing excessive overdrive of the bit lines.
    Type: Grant
    Filed: July 17, 1998
    Date of Patent: October 19, 1999
    Assignees: Texas Instruments Incorporated, Hitachi, Ltd.
    Inventors: Masayuki Hira, Shunichi Sukegawa, Shinji Bessho, Yasushi Takahashi, Koji Arai, Tsutomu Takahashi, Tsugio Takahashi
  • Patent number: 5892726
    Abstract: An address decoder with low power consumption of feedthrough current, leakage current, etc. Address bits AY0.sub.0 -AY0.sub.7 are respectively supplied to n-type gate terminals of CMOS transfer gates C.sub.0 -C.sub.7 and the gate terminals of PMOS transistors P.sub.0 -P.sub.7. Inverted address bits AY0.sub.0- -AY0.sub.7- are supplied to p-type gate terminals of the CMOS transfer gates C.sub.0 -C.sub.7. Enable signals AY3.sub.p, AY6.sub.q are respectively input to both input terminals of a NAND circuit 10. The output terminals of NAND circuit 10 are connected to the input terminals of CMOS transfer gates C.sub.0 -C.sub.7. The output terminals of CMOS transfer gates C.sub.0 -C.sub.7 are connected to the input terminals of the drivers D.sub.0 -D.sub.7 and the drain terminals of the PMOS transistors P.sub.0 -P.sub.7 via a node F.sub.0 -F.sub.7. The source terminals of PMOS transistors P.sub.0 -P.sub.7 are connected to a power supply voltage V.sub.cc, for example of 3.3 V. The output terminals of drivers D.sub.
    Type: Grant
    Filed: September 26, 1996
    Date of Patent: April 6, 1999
    Assignees: Texas Instruments Incorporated, Hitachi Ltd.
    Inventors: Yoojoon Moon, Shunichi Sukegawa, Yasuhito Ichimura, Makoto Saeki
  • Patent number: 5862086
    Abstract: A semiconductor storage device is provided with a storage circuit for a faulty address and a plurality of redundant word lines corresponding to the storage circuit. The storage circuit is adapted to store a faulty address required for selecting a redundant word line. The faulty address is compared with an address input at the time of memory access by a comparator. Using a coincidence signal produced from the comparator and a predetermined address signal contained in the input address, a defect relief circuit selects one of the redundant word lines in place of the faulty word line.
    Type: Grant
    Filed: August 22, 1996
    Date of Patent: January 19, 1999
    Assignees: Hitachi Ltd., Texas Instuments Incorporated
    Inventors: Chisa Makimura, Yukihide Suzuki, Shunichi Sukegawa, Hiroyuki Fujiwara, Masayuki Hira
  • Patent number: 5844915
    Abstract: A word line leak check test for a semiconductor memory arranged as a matrix which includes word lines and y-selection lines. First, a RAS signal is enabled while a prescribed row address is input, and word line 22 is driven to the Vpp level. Then, when the CAS signal is enabled, the voltage source is disconnected from word line 22, and word line 22 floats. Two bits for the column address are disregarded, and the Y selection signal line 23 is decoded without those 2 bits. By this means, 4 y-selection signal lines 23 are simultaneously enabled. When this condition has been maintained for a prescribed time T, a delayed write operation is conducted, and then it is determined whether the data has been correctly stored in memory cell 24.
    Type: Grant
    Filed: September 19, 1996
    Date of Patent: December 1, 1998
    Assignee: Texas Instruments Incorporated
    Inventors: Yoritaka Saitoh, Shunichi Sukegawa, Makoto Saeki, Yukihide Suzuki
  • Patent number: 5841688
    Abstract: A circuit is designed with a first lower conductor (500) having two ends. One end of the first lower conductor is coupled to a first signal source (386). A first upper conductor (544) has two ends and is spaced apart from the first lower conductor by a distance less than an allowable spacing between adjacent lower conductors. One end of the first upper conductor is coupled to a second signal source (384). A second upper conductor (508) has two ends. One end of the second upper conductor is coupled to another end of the first lower conductor for receiving a signal from the first signal source. A second lower conductor (552) has two ends and is spaced apart from the second upper conductor by a distance less than the allowable spacing between adjacent lower conductors. One end of the second lower conductor is coupled to another end of the first upper conductor for receiving a signal from the second signal source.
    Type: Grant
    Filed: June 27, 1997
    Date of Patent: November 24, 1998
    Assignee: Texas Instruments Incorporated
    Inventors: Shunichi Sukegawa, Hugh P. McAdams, Tadashi Tachibana, Katsuo Komatsuzaki, Takeshi Sakai
  • Patent number: 5831910
    Abstract: A semiconductor integrated circuit is provided in which a differential amplifier circuit such as a sense amplifier is operated at high speed even if the operating voltage is reduced. To achieve this, a MOS transistor for supplying the operating voltage to a drive line on the high-potential side of a differential amplifier circuit is of N-channel type and the amplitude of a switching control signal for controlling this transistor is the potential of the step-up voltage produced by stepping up a supply voltage in level. The output voltage of an internal step-up circuit for achieving a word-line selection level is utilizable as the step-up voltage.
    Type: Grant
    Filed: August 16, 1996
    Date of Patent: November 3, 1998
    Assignees: Hitachi, Ltd., Texas Instruments Incorporated
    Inventors: Yukihide Suzuki, Noriaki Kubota, Kouji Arai, Tsugio Takahashi, Shunichi Sukegawa, Koichi Abe
  • Patent number: 5828241
    Abstract: A signal transmission circuit which enables the distance of signal transmission as measured by the length of the wiring electrically connecting a driver circuit and a receiver circuit of the signal transmission circuit to be increased, while the signal delay and power consumption are reduced. The signal transmission circuit includes the driver circuit, the receiver circuit, an equalizer circuit that flattens the output of the driver circuit, and an intermediate amplifier circuit. The intermediate amplifier circuit is connected to input/output shared terminals in the wiring that connects the driver circuit and the receiver circuit. With the aid of the positive feedback of the intermediate amplifier circuit, a differential signal output from the driver circuit is amplified and then transmitted to the receiver circuit.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: October 27, 1998
    Assignee: Texas Instruments Incorporated
    Inventor: Shunichi Sukegawa
  • Patent number: 5805522
    Abstract: An address access path control circuit designed for shorter access time and small the layout area with low power consumption and noise. Our control circuit has a latching circuit LMO2A, a main output circuit MO3, and a common-bus driving circuit CBD for holding the level of a pair of common-buses CB/CB.sub.-- at the ground level during a prescribed period of time in which address transition takes place while the read data is output to common-buses CB/CB.sub.-- at a timing corresponding to the address signal. A data output buffer DO-BUF outputs to the outside the data transmitted from common-buses CB/CB.sub.-- to data output lines OD/OD.sub.-- in response to the input of control signal DOE. A control signal DOE is input to data output buffer DO-BUF during the period in which data output lines OD/OD.sub.-- are at the ground level.
    Type: Grant
    Filed: August 30, 1996
    Date of Patent: September 8, 1998
    Assignee: Texas Insturments Incorporated
    Inventors: Shunichi Sukegawa, Koichi Abe, Makoto Saeki, Yukihide Suzuki
  • Patent number: 5768214
    Abstract: A semiconductor memory device in which erroneous operation with respect to undesired level changes of the input address signal is prevented, and appropriate operation of the main amplifier is ensured. The semiconductor memory device has a main amplifier activating pulse generator 112' which includes response sensitivity reduction circuit 10, response sensitivity selector 12, and main amplifier activating pulse generator 14. The response sensitivity reduction circuit 10 can reduce the response sensitivity or input sensitivity of the circuit 112' with respect to an input address transition detection pulse ATD. The response sensitivity selector 12 selects either a first input terminal A1 or a second input terminal A2, depending on the output state of the main amplifier activating pulse generator 14.
    Type: Grant
    Filed: August 9, 1996
    Date of Patent: June 16, 1998
    Assignee: Texas Instruments Incorporated
    Inventors: Ken Saitoh, Shunichi Sukegawa, Tadashi Tachibana, Makoto Saeki, Yukihide Suzuki
  • Patent number: 5764580
    Abstract: A semiconductor integrated circuit capable of preventing the excessive overdriving of sense amplifiers when the supply voltage fed thereto is raised. The integrated circuit has differential amplifiers for amplifying a potential difference on complementary signal lines, and a control circuit for generating a first driving control signal for supplying the differential amplifiers with a first driving voltage as an overdriving power supply therefor. The control circuit further generates a second driving control signal for supplying the differential amplifiers with a second driving voltage which is activated after the activated first driving control signal is deactivated and which is lower in level than the first driving voltage. The control circuit includes a MOS circuit as a delay circuit composed of MOS transistors for defining a time interval from the time the first driving control signal is activated until the second driving control signal is activated.
    Type: Grant
    Filed: August 16, 1996
    Date of Patent: June 9, 1998
    Assignees: Hitachi, Ltd., Texas Instruments Incorporated
    Inventors: Yukihide Suzuki, Tsugio Takahashi, Shunichi Sukegawa, Koichi Abe
  • Patent number: 5761149
    Abstract: A dynamic RAM is provided with a main word lines; a plurality of subsidiary word lines which are arranged in the direction of bit lines crossing the main word line and to which a plurality of dynamic memory cells are connected; a plurality of subsidiary word selection lines which are extended so as to perpendicularly intersect the main word line and through which a selection signal for selecting one of the plurality of subsidiary word lines is transmitted; and a logic circuit for receiving a selection signal from the main word line and a selection signal from each of the subsidiary word selection lines to thereby form a selection signal for selecting one of the subsidiary word lines. In the dynamic RAM, the voltage level of each of the main word line and the subsidiary word selection lines is made to be equal to the ground potential when the line is in a not-selected state.
    Type: Grant
    Filed: July 12, 1996
    Date of Patent: June 2, 1998
    Assignees: Hitachi, Ltd., Texas Instruments Inc.
    Inventors: Yukihide Suzuki, Kanehide Kenmizaki, Tsugio Takahashi, Masayuki Nakamura, Makoto Saeki, Chisa Makimura, Katsuo Komatsuzaki, Shunichi Sukegawa
  • Patent number: 5689465
    Abstract: To provide a semiconductor memory device characterized by the fact that it can prevent errors in the redundant memory address coincidence signal generating circuit caused by the intrinsic resistance of the fuse in the fuse decoder, and it has a redundant mechanism for generating the high-speed address coincidence signal.It has multiple logic gate means and fuses programmable by the gate output. The output signal of each fuse is wired to generate address coincidence signal.
    Type: Grant
    Filed: August 26, 1996
    Date of Patent: November 18, 1997
    Assignee: Texas Instruments Incorporated
    Inventors: Shunichi Sukegawa, Takumi Nasu, Hidetoshi Iwai
  • Patent number: 5596535
    Abstract: A semiconductor storage device equipped with redundant circuits designed to increase the operating speed and to simplify the layout by providing for the detection of the storage of a faulty address and access to the faulty address so as to substitute a spare word line for a faulty word line. The semiconductor storage device includes a MOSFET for causing current to flow through a pair of fuse means by a complementary address signal at one end of a fuse means corresponding to each bit of the faulty address. The other end thereof is connected to a wired OR logic so as to generate a decision signal. The fuse means corresponding to the MOSFET which is turned on by the faulty address signal is cut off to store a faulty address. The faulty address storage and comparison units can be formed with the pair of fuses and the MOSFET.
    Type: Grant
    Filed: June 28, 1994
    Date of Patent: January 21, 1997
    Assignee: Texas Instruments Incorporated
    Inventors: Tathunori Mushya, Masayasu Kawamura, Shunichi Sukegawa
  • Patent number: 5596537
    Abstract: A semiconductor device test circuit for inclusion on a semiconductor chip having a semiconductor device thereon, wherein a test mode with respect to the semiconductor device is not entered during normal use of the semiconductor device and the test mode can be entered without applying a voltage higher than the power supply voltage to an external terminal of the semiconductor device. The test circuit includes a decoder circuit which detects the matching of a first address input corresponding to a test mode, and a latch circuit which latches the signal indicating the matching of the first address input with a test mode. A second decoder circuit then detects the matching of a second address to the test mode, the second address being input when the matching signal for the first address has been latched. A second latch circuit latches the signal indicating the matching of the second address. A third address input is processed by a third decoder circuit and a third latch circuit in the same way.
    Type: Grant
    Filed: July 14, 1994
    Date of Patent: January 21, 1997
    Assignees: Texas Instruments Incorporated, Hitachi Ltd.
    Inventors: Shunichi Sukegawa, Shiyuzo Shiozaki, Hiromi Matsuura, Masaya Muranaka
  • Patent number: 5557580
    Abstract: A word line driving circuit which effectively prevents ground noise during word line discharge along with accommodating the narrowing of pitch in the word lines by making the layout area of the word line driver small. The word line driving circuit includes n-type MOS transistor 14 and p-type MOS transistor 12. The drain terminal of n-type MOS transistor 14 and drain terminal of p-type MOS transistor 12 in word line driver 10 are connected to the base terminal of word line WLi. The output terminal of an output transistor driving circuit 16 is connected to the source terminal of p-type MOS transistor 12, and the output terminal of a first output transistor controlling circuit 18 is connected to the gate terminal. The output terminal of a second output transistor controlling circuit 20 is connected to the gate terminal of n-type MOS transistor 14, and a ground terminal 22 as a reference potential terminal for leading in the electric current is connected to the source terminal.
    Type: Grant
    Filed: August 18, 1994
    Date of Patent: September 17, 1996
    Assignees: Texas Instruments Incorporated, Hitachi, Ltd.
    Inventors: Shigeki Numaga, Shunichi Sukegawa, Takashi Inui, Yukihide Suzuki, Kiyoshi Nakai
  • Patent number: 5550394
    Abstract: To provide a semiconductor memory device characterized by the fact that it can prevent errors in the redundant memory address coincidence signal generating circuit caused by the intrinsic resistance of the fuse in the fuse decoder, and it has a redundant mechanism for generating the high-speed address coincidence signal. It has multiple logic gate means and fuses programmable by the gate output. The output signal of each fuse is wired to generate address coincidence signal.
    Type: Grant
    Filed: June 18, 1993
    Date of Patent: August 27, 1996
    Assignees: Texas Instruments Incorporated, Hitachi, Ltd.
    Inventors: Shunichi Sukegawa, Takumi Nasu, Hidetoshi Iwai
  • Patent number: 5487040
    Abstract: To provide a type of semiconductor memory device characterized by the fact that the area occupied by the redundant memory address decoder on the chip is minimized without reducing the redundancy of the defective memory, and hence the cost of the semiconductor memory device can be cut.It has both redundant decoders that select the redundant memory in response to the all address bits and the redundant decoders which select the redundant memory group in response to a portion of the address bits, so as to increase the efficiency in saving the defective memory.
    Type: Grant
    Filed: July 12, 1993
    Date of Patent: January 23, 1996
    Assignees: Texas Instruments Incorporated, Hitachi Ltd.
    Inventors: Shunichi Sukegawa, Tetsuya Saeki
  • Patent number: 5487039
    Abstract: A semiconductor memory device with a redundant circuit architecture having improved repairing efficiency and improved yield comprising a memory array (1) divided between a number of subarrays, in which a number of memory cells MCL are arrayed in matrix form; circuits (6-8) and (11-13), which select the subarrays SUB0-SUB7 based on the address signal in order to drive the cell with the specified address; a number of spare word sets SWLS, situated to correspond to the subarrays SUB0-SUB7; a number of fuse sets (3A), which are situated to correspond to the spare word sets SWLS, and which output signals used to replace the selection drive circuit being driven with a spare word set SWLS; and a circuit (3A), used to switch as desired between the output lines for the output signals of the fuse sets; wherein the aforementioned output lines are installed to correspond to the spare word sets (SWLS), and the selection and drive circuits are allowed to select the subarrays SUB0-SUB7 corresponding to the output lines.
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: January 23, 1996
    Assignee: Texas Instruments Incorporated
    Inventor: Shunichi Sukegawa
  • Patent number: 5485425
    Abstract: There is provided a semiconductor memory device having a redundant column. This memory device has a redundant column disposed in the direction of the Y-system address, a ROM accessed by using an X-system address, a Y-system address signal having a defective cell included in the cells therein being electrically written into the ROM, a comparator circuit for comparing a signal read out from this ROM with a Y-system address signal and outputting a coincidence signal upon coincidence, and a defect relieving circuit responsive to output of the coincidence signal from this comparator circuit to cause selection of the redundant column of Y system instead of the Y-system address selection device.
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: January 16, 1996
    Assignees: Hitachi, Ltd., Texas Instruments Incorporated
    Inventors: Hidetoshi Iwai, Masaya Muranaka, Takumi Nasu, Shunichi Sukegawa