Patents by Inventor Raminda U. Madurawe

Raminda U. Madurawe 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: 6108239
    Abstract: A compact nonvolatile programmable memory cell. The memory cell has a floating gate (118), control gate (123), drain (108), and source regions (112). The memory cell is an electrically erasable programmable read only memory (EEPROM) cell or a Flash memory cell. Data may be stored the memory cell of the present invention for the required lifetime of the memory cell usage, and data is retained even when power is removed. The memory cell of the present invention has a substantially transverse or vertical channel (140), relative to a surface of a substrate. The memory may be used to create very high-density memory arrays.
    Type: Grant
    Filed: May 26, 1999
    Date of Patent: August 22, 2000
    Assignee: Altera Corporation
    Inventors: Seshan Sekariapuram, Raminda U. Madurawe
  • Patent number: 6091102
    Abstract: A compact nonvolatile programmable memory cell. The memory cell has a floating gate (118), control gate (123), drain (108), and source regions (112). The memory cell is an electrically erasable programmable read only memory (EEPROM) cell or a Flash memory cell. Data may be stored the memory cell of the present invention for the required lifetime of the memory cell usage, and data is retained even when power is removed. The memory cell of the present invention has a substantially transverse or vertical channel (140), relative to a surface of a substrate. The memory may be used to create very high-density memory arrays.
    Type: Grant
    Filed: March 13, 1998
    Date of Patent: July 18, 2000
    Assignee: Altera Corporation
    Inventors: Seshan Sekariapuram, Raminda U. Madurawe
  • Patent number: 6081449
    Abstract: A compact nonvolatile programmable memory cell. The memory cell has a floating gate (118), control gate (123), drain (108), and source regions (112). The memory cell is an electrically erasable programmable read only memory (EEPROM) cell or a Flash memory cell. Data may be stored the memory cell of the present invention for the required lifetime of the memory cell usage, and data is retained even when power is removed. The memory cell of the present invention has a substantially transverse or vertical channel (140), relative to a surface of a substrate. The memory may be used to create very high-density memory arrays.
    Type: Grant
    Filed: May 26, 1999
    Date of Patent: June 27, 2000
    Assignee: Altera Corporation
    Inventors: Seshan Sekariapuram, Raminda U. Madurawe
  • Patent number: 6078521
    Abstract: A memory cell (400) used to store data in an integrated circuit. The memory cell (400) is static, nonvolatile, and programmable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a programmable memory element (515). In one embodiment, the programmable memory element (515) is coupled between supply voltage (510) and an output node (405). A pull-down device (525) is coupled between another supply voltage (505) and the output node (405). The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: August 30, 1999
    Date of Patent: June 20, 2000
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, James D. Sansbury
  • Patent number: 6052309
    Abstract: A memory cell (400) used to store data in an integrated circuit. The memory cell (400) is static, nonvolatile, and programmable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a programmable memory element (515). In one embodiment, the programmable memory element (515) is coupled between supply voltage (510) and an output node (405). A pull-down device (525) is coupled between another supply voltage (505) and the output node (405). The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: August 30, 1999
    Date of Patent: April 18, 2000
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, James D. Sansbury
  • Patent number: 6028787
    Abstract: A memory cell (400) for storing data on an integrated circuit. The memory cell (400) is static, nonvolatile, and reprogrammable. The layout of the memory cell is compact. In a first state, the logic output from this memory cell (400) is at about voltage level at a first conductor (505); and in a second state, the logic output is at about a voltage level at a second conductor (510). The memory cell (400) of the present invention includes a first programmable memory element (515) and a second programmable memory element (520). First programmable memory element (515) is coupled between the first conductor (505) and a sensing node (405). Second programmable memory element (520) is coupled between the sensing node (405) and the second conductor (510). In the first state, first programmable memory element (515) is not programmed, while the second programmable memory element (520) is programmed.
    Type: Grant
    Filed: May 27, 1998
    Date of Patent: February 22, 2000
    Assignee: Altera Corporation
    Inventors: James D. Sansbury, Raminda U. Madurawe
  • Patent number: 6018476
    Abstract: A memory cell (400) used to store data in an integrated circuit. The memory cell (400) is static, nonvolatile, and programmable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a programmable memory element (515). In one embodiment, the programmable memory element (515) is coupled between supply voltage (510) and an output node (405). A pull-down device (525) is coupled between another supply voltage (505) and the output node (405). The memory cell (400) may be used to store she configuration information for a programmable logic device (121).
    Type: Grant
    Filed: November 18, 1997
    Date of Patent: January 25, 2000
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, James D. Sansbury
  • Patent number: 6005806
    Abstract: A memory cell (400) used to store data in an integrated circuit. The memory cell (400) is static, nonvolatile, and programmable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a programmable memory element (515). In one embodiment, the programmable memory element (515) is coupled between supply voltage (510) and an output node (405). A pull-down device (525) is coupled between another supply voltage (505) and the output node (405). The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: September 16, 1996
    Date of Patent: December 21, 1999
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, James D. Sansbury
  • Patent number: 6002182
    Abstract: A technique to form a structure with a rough topography (415) in a planarized semiconductor process. The rough topography (415) is formed by creating cored contacts (433). Subsequent process layers may be further stacked on top of the cored contacts in order to augment the nonplanar characteristics of the cored contacts. This rough topography structure may be used to align integrated circuits and wafers. An integrated circuit may be laser aligned using this alignment structure.
    Type: Grant
    Filed: March 13, 1998
    Date of Patent: December 14, 1999
    Assignee: Altera Corporation
    Inventor: Raminda U. Madurawe
  • Patent number: 5998295
    Abstract: A technique to form a structure with a rough topography (415) in a planarized semiconductor process. The rough topography (415) is formed by creating cored contacts (433). Subsequent process layers may be further stacked on top of the cored contacts in order to augment the nonplanar characteristics of the cored contacts. This rough topography structure may be used to align integrated circuits and wafers. An integrated circuit may be laser aligned using this alignment structure.
    Type: Grant
    Filed: December 23, 1996
    Date of Patent: December 7, 1999
    Assignee: Altera Corporation
    Inventor: Raminda U. Madurawe
  • Patent number: 5998263
    Abstract: A compact nonvolatile programmable memory cell. The memory cell has a floating gate (118), control gate (123), drain (108), and source regions (112). The memory cell is an electrically erasable programmable read only memory (EEPROM) cell or a Flash memory cell. Data may be stored the memory cell of the present invention for the required lifetime of the memory cell usage, and data is retained even when power is removed. The memory cell of the present invention has a substantially transverse or vertical channel (140), relative to a surface of a substrate. The memory may be used to create very high-density memory arrays.
    Type: Grant
    Filed: May 12, 1997
    Date of Patent: December 7, 1999
    Assignee: Altera Corporation
    Inventors: Seshan Sekariapuram, Raminda U. Madurawe
  • Patent number: 5949710
    Abstract: A static, nonvolatile, and reprogrammable programmable interconnect junction cell for implementing programmable interconnect in an integrated circuit. The programmable interconnect junction (600) is programmably configured to couple or decouple a first interconnect line (210) and a second interconnect line (220). The configured state of the programmable interconnect junction is detected directly, and memory cell detection circuitry such as sense amplifiers are not needed during normal operation. Full-rail voltages may be passed from the first interconnect line and the second interconnect line.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: September 7, 1999
    Assignee: Altera Corporation
    Inventors: Christopher J. Pass, James D. Sansbury, Raminda U. Madurawe, John E. Turner, Rakesh H. Patel, Peter J. Wright
  • Patent number: 5943267
    Abstract: A compact nonvolatile programmable memory cell. The memory cell has a floating gate (118), control gate (123), drain (108), and source regions (112). The memory cell is an electrically erasable programmable read only memory (EEPROM) cell or a Flash memory cell. Data may be stored the memory cell of the present invention for the required lifetime of the memory cell usage, and data is retained even when power is removed. The memory cell of the present invention has a substantially transverse or vertical channel (140), relative to a surface of a substrate. The memory may be used to create very high-density memory arrays.
    Type: Grant
    Filed: June 12, 1998
    Date of Patent: August 24, 1999
    Assignee: Altera Corporation
    Inventors: Seshan Sekariapuram, Raminda U. Madurawe
  • Patent number: 5905675
    Abstract: Disclosed is a method for biasing dual row line EEPROM cells. The new biasing scheme improves the data retention lifetime of an EEPROM cell by reducing the potential difference between the control gate and the write column of the cell, which reduces the tunnel oxide electric field. In a preferred embodiment, the method involves applying bias voltages to the control gate and write column of an EEPROM cell such that the potential difference between the control gate and the right column is no more than about 0.5 volts. By biasing the cell's write column to a positive voltage, the tunnel oxide field may be significantly reduced. Moreover, the invention provides a method of selecting a write column voltage based on a control gate voltage such that the tunnel oxide field is substantially balanced in all its modes. This biasing scheme minimizes SILC and improves cell reliability.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: May 18, 1999
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, Richard G. Smolen, Minchang Liang, James D. Sansbury, John E. Turner, John C. Costello, Myron W. Wong
  • Patent number: 5898630
    Abstract: A memory cell (400) for storing data on an integrated circuit. The memory cell (400) is dynamic, nonvolatile, and reprogrammable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a first programmable memory element (515). First programmable memory element (515) is coupled between a voltage source (510) and an output node (405). A charge pumping node (545) dynamically charges, through a charging transistor (525), the output node (405) to about VDD. When programmable memory element (515) is not programmed, the memory cell stores and outputs a logic low. When programmable memory element (515) is programmed, the memory cell stores and outputs a logic high. The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: November 3, 1997
    Date of Patent: April 27, 1999
    Assignee: Altera Corporation
    Inventor: Raminda U. Madurawe
  • Patent number: 5812450
    Abstract: A memory cell (400) for storing data on an integrated circuit. The memory cell (400) is static, nonvolatile, and reprogrammable. The layout of the memory cell is compact. In a first state, the logic output from this memory cell (400) is at about voltage level at a first conductor (505); and in a second state, the logic output is at about a voltage level at a second conductor (510). The memory cell (400) of the present invention includes a first programmable memory element (515) and a second programmable memory element (520). First programmable memory element (515) is coupled between the first conductor (505) and a sensing node (405). Second programmable memory element (520) is coupled between the sensing node (405) and the second conductor (510). In the first state, first programmable memory element (515) is not programmed, while the second programmable memory element (520) is programmed.
    Type: Grant
    Filed: August 22, 1996
    Date of Patent: September 22, 1998
    Assignee: Altera Corporation
    Inventors: James D. Sansbury, Raminda U. Madurawe
  • Patent number: 5805516
    Abstract: A memory cell (400) for storing data on an integrated circuit. The memory cell (400) is dynamic, nonvolatile, and reprogrammable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a first programmable memory element (515). First programmable memory element (515) is coupled between a voltage source (510) and an output node (405). A charge pumping node (545) dynamically charges, through a charging transistor (525), the output node (405) to about VDD. When programmable memory element (515) is not programmed, the memory cell stores and outputs a logic low. When programmable memory element (515) is programmed, the memory cell stores and outputs a logic high. The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: August 30, 1996
    Date of Patent: September 8, 1998
    Assignee: Altera Corporation
    Inventor: Raminda U. Madurawe
  • Patent number: 5740110
    Abstract: A memory cell (400) for storing data on an integrated circuit. The memory cell (400) is dynamic, nonvolatile, and reprogrammable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a first programmable memory element (515). First programmable memory element (515) is coupled between a voltage source (510) and an output node (405). A charge pumping node (545) dynamically charges, through a charging transistor (525), the output node (405) to about VDD. When programmable memory element (515) is not programmed, the memory cell stores and outputs a logic low. When programmable memory element (515) is programmed, the memory cell stores and outputs a logic high. The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: August 30, 1996
    Date of Patent: April 14, 1998
    Assignee: Altera Corporation
    Inventor: Raminda U. Madurawe
  • Patent number: 5729495
    Abstract: A memory cell (400) for storing data on an integrated circuit. The memory cell (400) is dynamic, nonvolatile, and reprogrammable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a first programmable memory element (515). First programmable memory element (515) is coupled between a voltage source (510) and an output node (405). A charge pumping node (545) dynamically charges, through a charging transistor (525), the output node (405) to about VDD. When programmable memory element (515) is not programmed, the memory cell stores and outputs a logic low. When programmable memory element (515) is programmed, the memory cell stores and outputs a logic high. The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: September 29, 1995
    Date of Patent: March 17, 1998
    Assignee: Altera Corporation
    Inventor: Raminda U. Madurawe
  • Patent number: 5581501
    Abstract: A memory cell (400) for storing data on an integrated circuit. The memory cell (400) is static, nonvolatile, and reprogrammable. The layout of the memory cell is compact. In a first state, a logic high output from this memory cell (400) is at about VDD; and in a second state, a logic low output is about VSS. The memory cell (400) of the present invention includes a first programmable memory element (515) and a second programmable memory element (520). First programmable memory element (515) is coupled between VDD (505) and a sensing node (405). Second programmable memory element (520) is coupled between the sensing node (405) and VSS (510). In the first state, first programmable memory element (515) is not programmed, while the second programmable memory element (520) is programmed. In the second state, first programmable memory element (515) is programmed, while second programmable memory element (520) is not programmed.
    Type: Grant
    Filed: August 17, 1995
    Date of Patent: December 3, 1996
    Assignee: Altera Corporation
    Inventors: James D. Sansbury, Raminda U. Madurawe