Patents by Inventor Mehrdad Mofidi

Mehrdad Mofidi 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: 7064980
    Abstract: When programming a contiguous page of memory storage units, every time a memory storage unit has reached its targeted state and is program-inhibited or locked out from further programming, it creates a perturbation on an adjacent memory storage unit still under programming. The present invention provides as part of a programming circuit and method in which an offset to the perturbation is added to the adjacent memory storage unit still under programming. The offset is added by a controlled coupling between the adjacent bit lines of the program-inhibited memory storage unit and the still under programming memory storage unit. In this way, an error inherent in programming in parallel high-density memory storage units is eliminated or minimized.
    Type: Grant
    Filed: September 17, 2003
    Date of Patent: June 20, 2006
    Assignee: SanDisk Corporation
    Inventors: Raul-Adrian Cernea, Yan Li, Mehrdad Mofidi, Shahzad Khalid
  • Publication number: 20060034121
    Abstract: When programming a contiguous page of memory storage units, every time a memory storage unit has reached its targeted state and is program-inhibited or locked out from further programming, it creates a perturbation on an adjacent memory storage unit still under programming. The present invention provides as part of a programming circuit and method in which an offset to the perturbation is added to the adjacent memory storage unit still under programming. The offset is added as voltage offset to a bit line of a storage unit under programming. The voltage offset is a predetermined function of whether none or one or both of its neighbors are in a mode that creates perturbation, such as in a program inhibit mode. In this way, an error inherent in programming in parallel high-density memory storage units is eliminated or minimized.
    Type: Application
    Filed: October 13, 2005
    Publication date: February 16, 2006
    Inventors: Shahzad Khalid, Yan Li, Raul-Adrian Cernea, Mehrdad Mofidi
  • Patent number: 6956770
    Abstract: When programming a contiguous page of memory storage units, every time a memory storage unit has reached its targeted state and is program-inhibited or locked out from further programming, it creates a perturbation on an adjacent memory storage unit still under programming. The present invention provides as part of a programming circuit and method in which an offset to the perturbation is added to the adjacent memory storage unit still under programming. The offset is added as voltage offset to a bit line of a storage unit under programming. The voltage offset is a predetermined function of whether none or one or both of its neighbors are in a mode that creates perturbation, such as in a program inhibit mode. In this way, an error inherent in programming in parallel high-density memory storage units is eliminated or minimized.
    Type: Grant
    Filed: September 17, 2003
    Date of Patent: October 18, 2005
    Assignee: SanDisk Corporation
    Inventors: Shahzad Khalid, Yan Li, Raul-Adrian Cernea, Mehrdad Mofidi
  • Publication number: 20050057965
    Abstract: When programming a contiguous page of memory storage units, every time a memory storage unit has reached its targeted state and is program-inhibited or locked out from further programming, it creates a perturbation on an adjacent memory storage unit still under programming. The present invention provides as part of a programming circuit and method in which an offset to the perturbation is added to the adjacent memory storage unit still under programming. The offset is added by a controlled coupling between the adjacent bit lines of the program-inhibited memory storage unit and the still under programming memory storage unit. In this way, an error inherent in programming in parallel high-density memory storage units is eliminated or minimized.
    Type: Application
    Filed: September 17, 2003
    Publication date: March 17, 2005
    Inventors: Raul-Adrian Cernea, Yan Li, Mehrdad Mofidi, Shahzad Khalid
  • Publication number: 20050057967
    Abstract: When programming a contiguous page of memory storage units, every time a memory storage unit has reached its targeted state and is program-inhibited or locked out from further programming, it creates a perturbation on an adjacent memory storage unit still under programming. The present invention provides as part of a programming circuit and method in which an offset to the perturbation is added to the adjacent memory storage unit still under programming. The offset is added as voltage offset to a bit line of a storage unit under programming. The voltage offset is a predetermined function of whether none or one or both of its neighbors are in a mode that creates perturbation, such as in a program inhibit mode. In this way, an error inherent in programming in parallel high-density memory storage units is eliminated or minimized.
    Type: Application
    Filed: September 17, 2003
    Publication date: March 17, 2005
    Inventors: Shahzad Khalid, Yan Li, Raul-Adrian Cernea, Mehrdad Mofidi
  • Patent number: 6829673
    Abstract: An EEPROM system includes flash EEPROM cells organized into subarrays. Pairs of subarrays share row address decoders by sharing word lines, and individual subarrays have dedicated column address decoders and data registers. Each row decoder has an associated row address latch, and each column decoder has an associated column address latch. Multiple data chunks are concurrently written into the subarrays by first latching chunk addresses into the row and column address latches, and corresponding chunks of data into the data registers, then activating a programming signal to initiate concurrent programming and verifying the programming of the data chunks.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: December 7, 2004
    Assignee: SanDisk Corporation
    Inventors: Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra, Raul-Adrian Cernea
  • Publication number: 20030200380
    Abstract: An EEPROM system includes flash EEPROM cells organized into subarrays. Pairs of subarrays share row address decoders by sharing word lines, and individual subarrays have dedicated column address decoders and data registers. Each row decoder has an associated row address latch, and each column decoder has an associated column address latch. Multiple data chunks are concurrently written into the subarrays by first latching chunk addresses into the row and column address latches, and corresponding chunks of data into the data registers, then activating a programming signal to initiate concurrent programming and verifying the programming of the data chunks.
    Type: Application
    Filed: May 27, 2003
    Publication date: October 23, 2003
    Inventors: Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra, Raul-Adrian Cernea
  • Patent number: 6542956
    Abstract: An EEPROM system includes flash EEPROM cells organized into subarrays. Pairs of subarrays share row address decoders by sharing word lines, and individual subarrays have dedicated column address decoders and data registers. Each row decoder has an associated row address latch, and each column decoder has an associated column address latch. Multiple data chunks are concurrently written into the subarrays by first latching chunk addresses into the row and column address latches, and corresponding chunks of data into the data registers, then activating a programming signal to initiate concurrent programming and verifying the programming of the data chunks.
    Type: Grant
    Filed: August 21, 2000
    Date of Patent: April 1, 2003
    Assignee: SanDisk Corporation
    Inventors: Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra, Raul-Adrian Cernea
  • Publication number: 20030061437
    Abstract: An EEPROM system includes flash EEPROM cells organized into subarrays. Pairs of subarrays share row address decoders by sharing word lines, and individual subarrays have dedicated column address decoders and data registers. Each row decoder has an associated row address latch, and each column decoder has an associated column address latch. Multiple data chunks are concurrently written into the subarrays by first latching chunk addresses into the row and column address latches, and corresponding chunks of data into the data registers, then activating a programming signal to initiate concurrent programming and verifying the programming of the data chunks.
    Type: Application
    Filed: November 1, 2002
    Publication date: March 27, 2003
    Inventors: Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra, Raul-Adrian Cernea
  • Patent number: 6157983
    Abstract: An EEPROM system includes flash EEPROM cells organized into subarrays. Pairs of subarrays share row address decoders by sharing word lines, and individual subarrays have dedicated column address decoders and data registers. Each row decoder has an associated row address latch, and each column decoder has an associated column address latch. Multiple data chunks are concurrently written into the subarrays by first latching chunk addresses into the row and column address latches, and corresponding chunks of data into the data registers, then activating a programming signal to initiate concurrent programming and verifying the programming of the data chunks.
    Type: Grant
    Filed: January 6, 1999
    Date of Patent: December 5, 2000
    Assignee: SanDisk Corporation
    Inventors: Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra, Raul-Adrian Cernea
  • Patent number: 6069039
    Abstract: An EEPROM device having a plurality of flash EEPROM cells organized in right and left half memory planes each having right and left quad memory blocks is described along with corresponding control circuitry including erase circuitry for concurrently erasing selected addressable data sectors of the EEPROM device. Included in the erase circuitry are a plurality of erase voltage generating circuits, a corresponding plurality of switching circuitry, and switch control circuitry shared by the plurality of switching circuitry for controlling the selectable coupling of erase voltages generated by the erase voltage generating circuits to corresponding data sectors of the EEPROM device.
    Type: Grant
    Filed: April 21, 1998
    Date of Patent: May 30, 2000
    Assignee: SanDisk Corporation
    Inventors: Douglas J. Lee, Sanjay Mehrotra, Mehrdad Mofidi, Daniel C. Guterman
  • Patent number: 5890192
    Abstract: An EEPROM system includes flash EEPROM cells organized into subarrays. Pairs of subarrays share row address decoders by sharing word lines, and individual subarrays have dedicated column address decoders and data registers. Each row decoder has an associated row address latch, and each column decoder has an associated column address latch. Multiple data chunks are concurrently written into the subarrays by first latching chunk addresses into the row and column address latches, and corresponding chunks of data into the data registers, then activating a programming signal to initiate concurrent programming and verifying the programming of the data chunks.
    Type: Grant
    Filed: November 5, 1996
    Date of Patent: March 30, 1999
    Assignee: SanDisk Corporation
    Inventors: Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra, Raul-Adrian Cernea
  • Patent number: 5798968
    Abstract: An EEPROM device having a plurality of flash EEPROM cells organized in right and left half memory planes each having right and left quad memory blocks is described along with corresponding control circuitry including erase circuitry for concurrently erasing selected addressable data sectors of the EEPROM device. Included in the erase circuitry are a plurality of erase voltage generating circuits, a corresponding plurality of switching circuitry, and switch control circuitry shared by the plurality of switching circuitry for controlling the selectable coupling of erase voltages generated by the erase voltage generating circuits to corresponding data sectors of the EEPROM device.
    Type: Grant
    Filed: September 24, 1996
    Date of Patent: August 25, 1998
    Assignee: SanDisk Corporation
    Inventors: Douglas J. Lee, Sanjay Mehrotra, Mehrdad Mofidi, Daniel C. Guterman
  • Patent number: 5693570
    Abstract: A process for manufacturing a flash EEPROM system functioning as a mass storage medium for a host computer includes a controller and at least one flash EEPROM memory module. The flash EEPROM memory module includes at least one flash EEPROM chip having an on-chip programmable power generation circuit including a high voltage generator circuit capable of generating a high voltage Vpp from a logic level voltage Vdd provided to the chip, a serial protocol logic circuit, a data latch, a data bus, a register address decoder, and a multi-voltage generator/regulator. The multi-voltage generator/regulator includes a plurality of registers and provides the programming, reading, and erasing voltages required for proper operation of the flash EEPROM system from digital values stored in the plurality of registers by the controller. The high voltage generator circuit includes both high current and low current charge pump circuits for generating the high voltage Vpp.
    Type: Grant
    Filed: November 18, 1996
    Date of Patent: December 2, 1997
    Assignee: SanDisk Corporation
    Inventors: Raul-Ardian Cernea, Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra
  • Patent number: 5621685
    Abstract: An flash EEPROM system functioning as a mass storage medium for a host computer includes a controller and at least one flash EEPROM memory module. The flash EEPROM memory module includes at least one flash EEPROM chip having an on-chip programmable power generation circuit including a high voltage generator circuit capable of generating a high voltage Vpp from a logic level voltage Vdd provided to the chip, a serial protocol logic circuit, a data latch, a data bus, a register address decoder, and a multi-voltage generator/regulator. The multi-voltage generator/regulator includes a plurality of registers and provides the programming, reading, and erasing voltages required for proper operation of the flash EEPROM system from digital values stored in the plurality of registers by the controller. The high voltage generator circuit includes both high current and low current charge pump circuits for generating the high voltage Vpp.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: April 15, 1997
    Assignee: SanDisk Corporation
    Inventors: Raul-Adrian Cernea, Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra
  • Patent number: 5596532
    Abstract: An EEPROM system operative within a continuous source voltage range includes a controller having a processor and a memory, and an EEPROM module connected to the controller and including a plurality of EEPROM chips. A representative one of the EEPROM chips includes a comparator, a programmable voltage generator, and a regulated charge pump circuit. The comparator compares a source voltage provided to the EEPROM system against one or more reference voltages indicative of subranges within the operative source voltage range, to generate one or more control signals indicative of the subrange within which the source voltage resides. The regulated charge pump circuit generates from the source voltage, a regulated high voltage output which is substantially unaffected by changes in the source voltage. Included in the regulated charge pump circuit are a feedback circuit, and an open loop gain adjustment circuit which is responsive to the the one or more control signals generated by the comparator.
    Type: Grant
    Filed: October 18, 1995
    Date of Patent: January 21, 1997
    Assignee: SanDisk Corporation
    Inventors: Raul-Adrian Cernea, Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra
  • Patent number: 5592420
    Abstract: An flash EEPROM system functioning as a mass storage medium for a host computer includes a controller and at least one flash EEPROM memory module. The flash EEPROM memory module includes at least one flash EEPROM chip having an on-chip programmable power generation circuit including a high voltage generator circuit capable of generating a high voltage Vpp from a logic level voltage Vdd provided to the chip, a serial protocol logic circuit, a data latch, a data bus, a register address decoder, and a multi-voltage generator/regulator. The multi-voltage generator/regulator includes a plurality of registers and provides the programming, reading, and erasing voltages required for proper operation of the flash EEPROM system from digital values stored in the plurality of registers by the controller. The high voltage generator circuit includes both high current and low current charge pump circuits for generating the high voltage Vpp.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 7, 1997
    Assignee: SanDisk Corporation
    Inventors: Raul-Adrian Cernea, Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra
  • Patent number: 5568424
    Abstract: An flash EEPROM system functioning as a mass storage medium for a host computer includes a controller and at least one flash EEPROM memory module. The flash EEPROM memory module includes at least one flash EEPROM chip having an on-chip programmable power generation circuit including a high voltage generator circuit capable of generating a high voltage Vpp from a logic level voltage Vdd provided to the chip, a serial protocol logic circuit, a data latch, a data bus, a register address decoder, and a multi-voltage generator/regulator. The multi-voltage generator/regulator includes a plurality of registers and provides the programming, reading, and erasing voltages required for proper operation of the flash EEPROM system from digital values stored in the plurality of registers by the controller. The high voltage generator circuit includes both high current and low current charge pump circuits for generating the high voltage Vpp.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 22, 1996
    Assignee: SanDisk Corporation
    Inventors: Raul-Adrian Cernea, Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra
  • Patent number: 5563825
    Abstract: An flash EEPROM system functioning as a mass storage medium for a host computer includes a controller and at least one flash EEPROM memory module. The flash EEPROM memory module includes at least one flash EEPROM chip having an on-chip programmable power generation circuit including a high voltage generator circuit capable of generating a high voltage Vpp from a logic level voltage Vdd provided to the chip, a serial protocol logic circuit, a data latch, a data bus, a register address decoder, and a multi-voltage generator/regulator. The multi-voltage generator/regulator includes a plurality of registers and provides the programming, reading, and erasing voltages required for proper operation of the flash EEPROM system from digital values stored in the plurality of registers by the controller. The high voltage generator circuit includes both high current and low current charge pump circuits for generating the high voltage Vpp.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 8, 1996
    Assignee: SanDisk Corporation
    Inventors: Raul-Adrian Cernea, Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra
  • Patent number: 5508971
    Abstract: An flash EEPROM system functioning as a mass storage medium for a host computer includes a controller and at least one flash EEPROM memory module. The flash EEPROM memory module includes at least one flash EEPROM chip having an on-chip programmable power generation circuit including a high voltage generator circuit capable of generating a high voltage Vpp from a logic level voltage Vdd provided to the chip, a serial protocol logic circuit, a data latch, a data bus, a register address decoder, and a multi-voltage generator/regulator. The multi-voltage generator/regulator includes a plurality of registers and provides the programming, reading, and erasing voltages required for proper operation of the flash EEPROM system from digital values stored in the plurality of registers by the controller. The high voltage generator circuit includes both high current and low current charge pump circuits for generating the high voltage Vpp.
    Type: Grant
    Filed: October 17, 1994
    Date of Patent: April 16, 1996
    Assignee: SanDisk Corporation
    Inventors: Raul-Adrian Cernea, Douglas J. Lee, Mehrdad Mofidi, Sanjay Mehrotra