Patents by Inventor Takashi Akioka
Takashi Akioka 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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Patent number: 6625070Abstract: Parasitic capacitances formed between bit lines to which signals are to be read out of memory cells and a signal transmission line arranged above them are to be reduced. Second complementary global bit lines for transmitting data read out of memory cells MC via complementary bit lines are arranged above a memory cell array. Each second global bit line is so arranged that a triangle having as its vertexes the center of the section of one of the complementary bit lines, that of the section of the other and that of the section of the second global bit line arranged directly above these complementary bit lines be an isosceles triangle.Type: GrantFiled: December 11, 2001Date of Patent: September 23, 2003Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.Inventors: Hiroki Ueno, Takashi Akioka, Kinya Mitsumoto, Akihisa Aoyama, Masao Shinozaki
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Patent number: 6538933Abstract: Setting means (such as fuse circuits) for adjusting the timings of various signals such as an activation timing of a sense amplifier, a fall timing of a word line, a recovery operation (equalization) of a bit lines and so forth, checking an operation in a test stage of a chip, and permanently programming (fixing) the timing of an internal signal to the condition of the highest operation speed that can be confirmed as acquirable in this check stage, is provided.Type: GrantFiled: January 3, 2002Date of Patent: March 25, 2003Assignee: Hitachi, Ltd.Inventors: Takashi Akioka, Masao Shinozaki
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Publication number: 20020089881Abstract: Setting means (such as fuse circuitry) for adjusting the timings of various signals such as an activation timing of a sense amplifier, a fall timing of a word line, a recovery operation (equalization) of a bit lines and so forth, checking an operation in a test stage of a chip, and permanently programming (fixing) the timing of an internal signal to the condition of the highest operation speed that can be confirmed as acquirable in this check stage, is provided.Type: ApplicationFiled: January 3, 2002Publication date: July 11, 2002Applicant: Hitachi Ltd.Inventors: Takashi Akioka, Masao Shinozaki
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Publication number: 20020075732Abstract: Parasitic capacitances formed between bit lines to which signals are to be read out of memory cells and a signal transmission line arranged above them are to be reduced. Second complementary global bit lines for transmitting data read out of memory cells MC via complementary bit lines are arranged above a memory cell array. Each second global bit line is so arranged that a triangle having as its vertexes the center of the section of one of the complementary bit lines, that of the section of the other and that of the section of the second global bit line arranged directly above these complementary bit lines be an isosceles triangle.Type: ApplicationFiled: December 11, 2001Publication date: June 20, 2002Applicant: Hitachi, LtdInventors: Hiroki Ueno, Takashi Akioka, Kinya Mitsumoto, Akihisa Aoyama, Masao Shinozaki
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Publication number: 20020074572Abstract: The invention provides a method of producing a semiconductor device conforming to plural supply voltage specifications without increasing the chip size and the production cost, while the device achieves a high-speed performance. The method includes plural processes for forming plural types of MOS transistors supplied with different power supply voltages in correspondence with external power supply voltages, which are comprised of a first process common to the plural types of MOS transistors, a second process following the first process, which is different by each of the plural types of MOS transistors, and a third process following the second process, which is common to the plural types of MOS transistors.Type: ApplicationFiled: December 5, 2001Publication date: June 20, 2002Applicant: Hitachi, Ltd.Inventors: Masao Shinozaki, Takashi Akioka, Kinya Mitsumoto
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Patent number: 6366507Abstract: Setting means (such as fuse circuits) for adjusting the timings of various signals such as an activation timing of a sense amplifier, a fall timing of a word line, a recovery operation (equalization) of a bit lines and so forth, checking an operation in a test stage of a chip, and permanently programming (fixing) the timing of an internal signal to the condition of the highest operation speed that can be confirmed as acquirable in this check stage, is provided.Type: GrantFiled: September 1, 2000Date of Patent: April 2, 2002Assignee: Hitachi, Ltd.Inventors: Takashi Akioka, Masao Shinozaki
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Publication number: 20020024496Abstract: An image display which displays image data on an image display part constructed by a display pixel array, wherein an image data input circuit inputs image data into the image display part by selecting addresses in a row direction and a column direction of the display pixel array so that the display pixel array has two neighboring areas having different frame rates (>0). The display pixel array includes row direction address lines and column direction address lines. Display pixels of the display pixel array each include an AND functional circuit which is connected to one of the row direction address lines and one of the column direction address lines.Type: ApplicationFiled: October 15, 2001Publication date: February 28, 2002Inventors: Hajime Akimoto, Mitsuru Hiraki, Hitoshi Nakahara, Takashi Akioka, Yoshiyuki Kaneko, Makoto Tsumura, Yoshiro Mikami
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Patent number: 6329973Abstract: An image display for displaying image data on an image display part constructed by a display pixel array is disclosed. In an image display in which image data input means for inputting image data so that the display pixel array has two neighboring areas having different frame rates (>0) is provided or image data is displayed on an image display part constructed by a display pixel array, there is provided image data input means which can input at least one moving image data and at least one still image data into the image display part at different frame rates (>0). A high precision image display can be realized hardly changing a display pixel rewriting speed.Type: GrantFiled: March 20, 1998Date of Patent: December 11, 2001Assignee: Hitachi, Ltd.Inventors: Hajime Akimoto, Mitsuru Hiraki, Hitoshi Nakahara, Takashi Akioka, Yoshiyuki Kaneko, Makoto Tsumura, Yoshiro Mikami
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Patent number: 6032229Abstract: An information processor having a high performance as a whole is provided by improving the throughput of the processor and the semiconductor memory device. The information processor comprises a memory having a buffer for temporarily holding data and a processor having a memory interface part for controlling the memory to transfer data to the buffer before determining whether the data is to be written in the memory and to write the data in said memory after determining of writing. Data writing and reading to the semiconductor device is pipelined by justifying data exchange between reading and writing. Since the data transfer timings of reading from a memory and writing in the memory can be executed at the same time, the reading process and the writing process can be performed by pipeline-like process and the throughput can be improved.Type: GrantFiled: November 22, 1995Date of Patent: February 29, 2000Assignee: Hitachi, Ltd.Inventors: Takashi Hotta, Hideo Sawamoto, Noboru Akiyama, Takashi Akioka, Shigeya Tanaka
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Patent number: 5920510Abstract: A semiconductor device and a computer system, incorporating the same, is capable of capturing an external signal at a high speed and stably operating independent of the duty ratio of a clock signal. An external signal ADD is captured into an address latch 22 by a level latch. The level latch is controlled to a through state at the timing in which the external signal is decided and controlled to a latched state in the decision period of the external signal. A pulse generation circuit controls the timing for switching a latch to the through state to a desired timing by a pulse generation circuit 30 in a chip. According to the above structure, the capture of the external signal ADD can be accelerated because the capture of the signal is determined by the setup timing. Moreover, because a latching period is controlled by the pulse generation circuit in the chip, operations are performed in a stable manner without having to depend upon the pulse width of an external clock CLK.Type: GrantFiled: September 19, 1997Date of Patent: July 6, 1999Assignee: Hitachi, Ltd.Inventors: Seigou Yukutake, Takashi Akioka, Kinya Mitsumoto, Takahiro Nagano, Hideo Maejima
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Patent number: 5787043Abstract: A semiconductor device is provided which comprises a memory mat formed by dividing a memory into a plurality of blocks and a circuit arrangement disposed at every memory mat block for generating access suppression signals at least for defective memory cells within that block. Using this arrangement, the access speed to a redundant memory cell array for relieving the defects is increased so that a semiconductor memory device capable of a high speed operation is obtained.Type: GrantFiled: February 27, 1995Date of Patent: July 28, 1998Assignee: Hitachi, Ltd.Inventors: Takashi Akioka, Yuji Yokoyama, Atsushi Hiraishi, Masahiro Iwamura, Yutaka Kobayashi, Tatsumi Yamauchi, Shigeru Takahashi, Koichi Motohashi
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Patent number: 5761150Abstract: There is provided a method of controlling an internal address signal of an RAM in which a late-write method is realized on a chip. Two sets of address registers for reading and writing are provided for each address and further a middle register is provided between the two sets of address registers. The middle register is controlled by a signal formed by obtaining the AND result of a clock signal and a write enable signal and the two sets of address registers for reading and writing are controlled only by the clock signal. A selection circuit selects outputs of the two sets of address registers as an input in accordance with the write enable signal to control an internal address.Type: GrantFiled: May 21, 1996Date of Patent: June 2, 1998Assignee: Hitachi, Ltd.Inventors: Seigoh Yukutake, Kinya Mitsumoto, Takashi Akioka, Masahiro Iwamura, Noboru Akiyama
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Patent number: 5742551Abstract: A constant current source is connected in series to a current source circuit including a MOS transistor which is used as a current source for a differential output amplifier circuit, an emitter follower circuit or a source follower circuit used with a semiconductor integrated circuit. In a multiplex circuit, an input signal is inputted to each of base terminals of a plurality of bipolar transistors. When one input signal is selected, the bipolar transistor corresponding to the selected input signal is made to be operable with an input signal from a signal input terminal by a control circuit. The bipolar transistors corresponding to the non-selection input signals are turned OFF irrespective of potential levels of the individual input signals by current drawing circuits.Type: GrantFiled: June 5, 1995Date of Patent: April 21, 1998Assignee: Hitachi, Ltd.Inventors: Seigoh Yukutake, Yutaka Kobayashi, Takashi Akioka, Masahiro Iwamura
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Patent number: 5680066Abstract: A semiconductor device which includes at least one of (1) an input buffer circuit formed of an input level converter and a non-inverting buffer circuit and an inverting buffer circuit each including BiCMOS circuitry which effects high-speed operation; (2) a decoder circuit formed of plural logic gates each of which is composed of the combination of MOS and bipolar circuitry; (3) a sense amplifier circuit including a multiemitter transistor; (4) a signal or address transition detector circuit which includes input circuits each receiving, for example, an address signal of a voltage amplitude and outputting a current amplitude signal in response to a change in level of the address signal, and a detector circuit connected thereto which has a cascode amplifier arranged such that it receives current amplitude signals at an input thereof and in which the cascode amplifier input is maintained at a substantially constant voltage, in which the detection circuit detects a transition of one or more of the current amplituType: GrantFiled: January 13, 1994Date of Patent: October 21, 1997Assignee: Hitachi, Ltd.Inventors: Takashi Akioka, Masahiro Iwamura, Atsushi Hiraishi, Yuji Yokoyama, Nozomu Matsuzaki, Tatsumi Yamauchi, Yutaka Kobayashi, Nobuyuki Gotou, Akira Ide, Masahiro Yamamura, Hideaki Uchida
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Patent number: 5675548Abstract: An arrangement which is particularly effective for decoders in semiconductor memory circuits which use, for example, common NMOS to receive one input for a plurality of logic decoder gates is provided includes a plurality of logic gates each having a first input terminal for respectively receiving first input signals and each being coupled to a common node. In one embodiment, first and second switching elements are also coupled to the common node. The first and second switching elements are both coupled to a second input terminal for receiving a second input signal which is common to the plurality of logic gates, and both operate complementary to one another in response to the second input signal. An improved read/write arrangement is also provided for such semiconductor memory circuit which includes circuitry to prevent connection of a common read line to the data lines during the writing operation. This enhances the writing speed by removing the load of the common read line during writing.Type: GrantFiled: February 29, 1996Date of Patent: October 7, 1997Assignee: Hitachi, Ltd.Inventors: Yuji Yokoyama, Takashi Akioka, Masahiro Iwamura, Atsushi Hiraishi, Yutaka Kobayashi, Tatsumi Yamauchi, Shigeru Takahashi, Nobuyuki Gotou, Akira Ide
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Patent number: 5661693Abstract: A synchronous memory device is provided in which the cycle time is shorter than conventional memory devices. For example, by providing an output latch in a sense amplifier on a bit line, the time period from input of a clock signal to latching data in the output latch is shortened. In case of plural bit lines, a selector for selecting data in a plural output latch and a latch for latching a sense amplifier selection are provided.Type: GrantFiled: November 22, 1995Date of Patent: August 26, 1997Assignee: Hitachi, Ltd.Inventors: Takashi Akioka, Noboru Akiyama, Masahiro Iwamura, Seigoh Yukutake
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Patent number: 5654931Abstract: A semiconductor integrated circuit device is divided into a plurality of blocks, which are individually equipped with signal generate units such that the signal generate units are distributed in the semiconductor integrated circuit device. The semiconductor integrated circuit device is preferably constructed to generate the pulse signal by the pulse generate units which are provided for the individual blocks, after all initial logic operations on the data and control signals have been taken. Thanks to this construction, an SRAM, for example, can have its write recovery time minimized to 0 so that it can achieve high-speed operations. Moreover, since predecoders are provided for the individual blocks, the wiring line number and area in the chip can be reduced to improve the degree of integration of the semiconductor integrated circuit device. Still moreover, signal delay and skew can be reduced in the chip so that high-speed can be achieved.Type: GrantFiled: March 16, 1994Date of Patent: August 5, 1997Assignee: Hitachi, Ltd.Inventors: Akihiro Tamba, Masahiro Iwamura, Yutaka Kobayashi, Kinya Mitsumoto, Tatsumi Yamauchi, Shuko Yamauchi, Takashi Akioka
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Patent number: 5646897Abstract: A logic circuit is provided for a memory device which can be operated at a high speed with a lower voltage power source level than conventional devices. This logic circuit can be used in a multi-bit test circuit executing the wired-OR-logic operation of complementary logic signals from a plurality of pre-sense amplifiers, receiving the output of the wired-OR-logic operation by an emitter follower using a bipolar transistor, and outputting an AND signal of the complementary logic signals by a level comparing circuit. A sense amplifier is also provided for executing the wired-OR-logic operation of complementary logic signals from a plurality of pre-sense amplifiers, raising the level of the output of the wired-OR-logic operation by a level shift circuit having a semiconductor element for applying an inverse bias potential to an input signal, executing the wired-OR-operation of the shifted up output and outputs from other blocks, and receiving and amplifying the output of the wired-OR-logic operation.Type: GrantFiled: April 21, 1995Date of Patent: July 8, 1997Assignee: Hitachi, Ltd.Inventors: Seigou Yukutake, Masahiro Iwamura, Kinya Mitsumoto, Takashi Akioka, Noboru Akiyama
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Patent number: 5638335Abstract: A memory device comprising a memory array having a plurality of bits, including parity bits, and comprising a plurality of memory blocks, and a bit structure changing section for changing the input/output bits of the memory array, wherein the number of the memory blocks are prescribed to be an integral multiple of three and the input/output bits of the plurality of memory blocks are even. Thereby, the bit structure of the semiconductor memory, having parity bits and which is capable of changing the input/output bits to a plurality of bit structures, can be changed while maintaining the bit structure of the memory blocks even and without increase in propagation delay time.Type: GrantFiled: May 17, 1996Date of Patent: June 10, 1997Assignee: Hitachi, Ltd.Inventors: Noboru Akiyama, Seigoh Yukutake, Sadayuki Ohkuma, Akihiko Emori, Takashi Akioka, Shuichi Miyaoka, Shinji Nakazato, Kinya Mitsumoto
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Patent number: 5631600Abstract: A constant current generating circuit is provided with a first current generating circuit unit which generates a first current having a positive temperature dependency and includes a pair of first and second bipolar transistors, a first current mirror circuit comprised of a plurality of first MOS transistors which regulates a current density ratio of the currents fed to the first and second bipolar transistors to be constant and derives the first current and a first circuit disposed between the first and second bipolar transistors and the first current mirror circuit for limiting dependency of the currents flowing through the first and second bipolar transistors on a voltage of a power source applied to the first current mirror circuit, a second current generating circuit unit is also provided which generates a second current having as negative temperature dependency and which includes a third bipolar transistor and a second resistor through which the second current is derived.Type: GrantFiled: December 23, 1994Date of Patent: May 20, 1997Assignee: Hitachi, Ltd.Inventors: Takashi Akioka, Kinya Mitsumoto, Yutaka Kobayashi