Patents by Inventor Robert D. Norman

Robert D. Norman 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).

  • Publication number: 20030014689
    Abstract: A system of Flash EEprom memory chips with controlling circuits serves as non-volatile memory such as that provided by magnetic disk drives. Improvements include selective multiple sector erase, in which any combinations of Flash sectors may be erased together. Selective sectors among the selected combination may also be de-selected during the erase operation. Another improvement is the ability to remap and replace defective cells with substitute cells. The remapping is performed automatically as soon as a defective cell is detected. When the number of defects in a Flash sector becomes large, the whole sector is remapped. Yet another improvement is the use of a write cache to reduce the number of writes to the Flash EEprom memory, thereby minimizing the stress to the device from undergoing too many write/erase cycling.
    Type: Application
    Filed: September 6, 2002
    Publication date: January 16, 2003
    Inventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
  • Patent number: 6462992
    Abstract: A system of Flash EEprom memory chips with controlling circuits serves as non-volatile memory such as that provided by magnetic disk drives. Improvements include selective multiple sector erase, in which any combinations of Flash sectors may be erased together. Selective sectors among the selected combination may also be de-selected during the erase operation. Another improvement is the ability to remap and replace defective cells with substitute cells. The remapping is performed automatically as soon as a defective cell is detected. When the number of defects in a Flash sector becomes large, the whole sector is remapped. Yet another improvement is the use of a write cache to reduce the number of writes to the Flash EEprom memory, thereby minimizing the stress to the device from undergoing too many write/erase cycling.
    Type: Grant
    Filed: January 18, 2001
    Date of Patent: October 8, 2002
    Assignee: SanDisk Corporation
    Inventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
  • Patent number: 6434034
    Abstract: A very small computer memory card is densely packed with a large number of flash EEPROM integrated circuit chips. A computer memory system provides for the ability to removably connect one or more of such cards with a common controller circuit that interfaces between the memory cards and a standard computer system bus. Alternately, each card can be provided with the necessary controller circuitry and thus is connectable directly to the computer system bus. An electronic system is described for a memory system and its controller within a single memory card. In a preferred physical arrangement, the cards utilize a main circuit board with a plurality of sub-boards attached thereto on both sides, each sub-board carrying several integrated circuit chips.
    Type: Grant
    Filed: June 22, 2001
    Date of Patent: August 13, 2002
    Assignee: SanDisk Corporation
    Inventors: Robert F. Wallace, Robert D. Norman, Eliyahou Harari
  • Patent number: 6396729
    Abstract: A memory system having a memory controller connected to multiple memory devices by way of a system bus. The memory controller issues device select, memory program and memory read instructions for the memory devices over the system bus, with the device select instructions including a device select address and a device select command. The memory devices each include an array of memory cells and a memory operation manager which functions to carry out memory read and program operations on the array. The memory operation manager includes an address comparator which compares the device select address received on the system bus with a local address stored in the memory device and a command decoder which detects commands on the system bus, with the memory operation manager operating to switch the memory device from a device-disabled state to a device-enabled state when the memory device receive a select address which matches the local address together with one of the device select commands.
    Type: Grant
    Filed: November 13, 2000
    Date of Patent: May 28, 2002
    Assignee: Micron Technology, Inc.
    Inventors: Robert D. Norman, Vinod C. Lakhani, Christophe J. Chevallier
  • Publication number: 20020046318
    Abstract: A system of Flash EEprom memory chips with controlling circuits serves as non-volatile memory such as that provided by magnetic disk drives. Improvements include selective multiple sector erase, in which any combinations of Flash sectors may be erased together. Selective sectors among the selected combination may also be de-selected during the erase operation. Another improvement is the ability to remap and replace defective cells with substitute cells. The remapping is performed automatically as soon as a defective cell is detected. When the number of defects in a Flash sector becomes large, the whole sector is remapped. Yet another improvement is the use of a write cache to reduce the number of writes to the Flash EEprom memory, thereby minimizing the stress to the device from undergoing too many write/erase cycling.
    Type: Application
    Filed: October 30, 2001
    Publication date: April 18, 2002
    Inventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotta
  • Patent number: 6373747
    Abstract: A system of Flash EEprom memory chips with controlling circuits serves as non-volatile memory such as that provided by magnetic disk drives. Improvements include selective multiple sector erase, in which any combinations of Flash sectors may be erased together. Selective sectors among the selected combination may also be de-selected during the erase operation. Another improvement is the ability to remap and replace defective cells with substitute cells. The remapping is performed automatically as soon as a defective cell is detected. When the number of defects in a Flash sector becomes large, the whole sector is remapped. Yet another improvement is the use of a write cache to reduce the number of writes to the Flash EEprom memory, thereby minimizing the stress to the device from undergoing too many write/erase cycling.
    Type: Grant
    Filed: April 14, 1998
    Date of Patent: April 16, 2002
    Assignee: SanDisk Corporation
    Inventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
  • Patent number: 6363454
    Abstract: A memory system having a single memory controller connected to several memory devices by way of a common bus, with the memory controller configured to issue memory program, memory read and memory erase instructions over the system bus to a selected one of the memory devices. Each memory device has an array of memory cells and several volatile control registers which contain control parameters provided by the memory controller. The control parameters operate to control one or more of the voltages applied to the array in memory read, program and erase operations, including the timing of the application of the voltages and the magnitude of the voltages so that the memory operations can be optimized by the memory controller.
    Type: Grant
    Filed: April 18, 2000
    Date of Patent: March 26, 2002
    Assignee: Micron Technology, Inc.
    Inventors: Vinod C. Lakhani, Robert D. Norman, Christophe J. Chevallier
  • Publication number: 20020032843
    Abstract: A memory system includes an array of solid-state memory devices are in communication with and under the control of a controller module via a device bus with very few lines. This forms an integrated-circuit mass storage system which is contemplated to replace a mass storage system such as a disk drive memory in a computer system. Command, address and data information are serialized into component strings and multiplexed before being transferred between the controller module and the array of memory devices. The serialized information are accompanied by a control signal to help sort out the multiplexed components. Each memory device in the array is assigned an array address by an array mount. An memory device is selected by an appropriate address broadcast over the device bus, without requiring the usual dedicated select signal. A reserved array mount configuration is used to unconditionally select the device mounted.
    Type: Application
    Filed: August 22, 2001
    Publication date: March 14, 2002
    Inventors: Karl M. J. Lofgren, Jeffrey Donald Stai, Anil Gupta, Robert D. Norman, Sanjay Mehrotra
  • Patent number: 6353571
    Abstract: A memory system having a memory controller connected to multiple memory devices by way of a system bus. The memory controller issues device select, memory program and memory read instructions for the memory devices over the system bus, with the device select instructions including a device select address and a device select command. The memory devices each include an array of memory cells and a memory operation manager which functions to carry out memory read and program operations on the array. The memory operation manager includes an address comparator which compares the device select address received on the system bus with a local address stored in the memory device and a command decoder which detects commands on the system bus, with the memory operation manager operating to switch the memory device from a device-disabled state to a device-enabled state when the memory device receive a select address which matches the local address together with one of the device select commands.
    Type: Grant
    Filed: November 13, 2000
    Date of Patent: March 5, 2002
    Assignee: Micron Technology, Inc.
    Inventors: Robert D. Norman, Vinod C. Lakhani, Christophe J. Chevallier
  • Publication number: 20020002653
    Abstract: A non-volatile memory system having a memory controller, an array of memory cells and a memory operation manager. The operation manager carries out memory program, read and erase operation upon receipt of program, read and erase instruction from the controller, typically over a system bus. The address block circuitry is provided in the manager which is capable of performing an memory operation on a single address or on multiple addresses depending upon the state of the address block circuitry as determined by the controller. Multiple addresses can be generated based upon a single address provided by the controller so that sectors of the memory can be programmed or read thereby simplifying memory operations and reducing the overhead of the memory controller.
    Type: Application
    Filed: May 11, 2001
    Publication date: January 3, 2002
    Applicant: Micron Technology, Inc.
    Inventors: Vinod C. Lakhani, Robert D. Norman, Christophe J. Chevallier
  • Patent number: 6320815
    Abstract: A memory system having a memory controller connected to multiple memory devices by way of a system bus. The memory controller issues device select, memory program and memory read instructions for the memory devices over the system bus, with the device select instructions including a device select address and a device select command. The memory devices each include an array of memory cells and a memory operation manager which functions to carry out memory read and program operations on the array. The memory operation manager includes an address comparator which compares the device select address received on the system bus with a local address stored in the memory device and a command decoder which detects commands on the system bus, with the memory operation manager operating to switch the memory device from a device-disabled state to a device-enabled state when the memory device receive a select address which matches the local address together with one of the device select commands.
    Type: Grant
    Filed: November 13, 2000
    Date of Patent: November 20, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Robert D. Norman, Vinod C. Lakhani, Christophe J. Chevallier
  • Patent number: 6317812
    Abstract: A memory system includes an array of solid-state memory devices are in communication with and under the control of a controller module via a device bus with very few lines. This forms an integrated-circuit mass storage system which is contemplated to replace a mass storage system such as a disk drive memory in a computer system. Command, address and data information are serialized into component strings and multiplexed before being transferred between the controller module and the array of memory devices. The serialized information are accompanied by a control signal to help sort out the multiplexed components. Each memory device in the array is assigned an array address by an array mount. An memory device is selected by an appropriate address broadcast over the device bus, without requiring the usual dedicated select signal. A reserved array mount configuration is used to unconditionally select the device mounted.
    Type: Grant
    Filed: September 8, 2000
    Date of Patent: November 13, 2001
    Inventors: Karl M. J. Lofgren, Jeffrey Donald Stai, Anil Gupta, Robert D. Norman, Sanjay Mehrotra
  • Publication number: 20010026472
    Abstract: A system of Flash EEprom memory chips with controlling circuits serves as non-volatile memory such as that provided by magnetic disk drives. Improvements include selective multiple sector erase, in which any combinations of Flash sectors may be erased together. Selective sectors among the selected combination may also be de-selected during the erase operation. Another improvement is the ability to remap and replace defective cells with substitute cells. The remapping is performed automatically as soon as a defective cell is detected. When the number of defects in a Flash sector becomes large, the whole sector is remapped. Yet another improvement is the use of a write cache to reduce the number of writes to the Flash EEprom memory, thereby minimizing the stress to the device from undergoing too many write/erase cycling.
    Type: Application
    Filed: May 30, 2001
    Publication date: October 4, 2001
    Inventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
  • Publication number: 20010024386
    Abstract: A system of Flash EEprom memory chips with controlling circuits serves as non-volatile memory such as that provided by magnetic disk drives. Improvements include selective multiple sector erase, in which any combinations of Flash sectors may be erased together. Selective sectors among the selected combination may also be de-selected during the erase operation. Another improvement is the ability to remap and replace defective cells with substitute cells. The remapping is performed automatically as soon as a defective cell is detected. When the number of defects in a Flash sector becomes large, the whole sector is remapped. Yet another improvement is the use of a write cache to reduce the number of writes to the Flash EEprom memory, thereby minimizing the stress to the device from undergoing too many write/erase cycling.
    Type: Application
    Filed: February 14, 2001
    Publication date: September 27, 2001
    Applicant: SanDisk Corporation
    Inventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
  • Patent number: 6292868
    Abstract: A method and system in which X-bit packets of bits (where X is an integer) are encoded to generate X-bit packets of encoded bits for writing to erased cells of a flash memory array, where less power is consumed to write a bit having a first value to an erased cell than to write a bit having a second value to the cell. Preferably, a count signal is generated for each packet of raw bits indicating the number of bits of the packet having the first (or second) value, the count signal is processed to generate a control signal which determines an encoding for the packet, and the raw bits of the packet are encoded according to a scheme determined by the control signal. In some embodiments, each erased cell is indicative of the binary value “1”, the count signal is compared to a reference value (indicative of X/2) to generate a control signal determining whether the packet should undergo polarity inversion, and the packet is inverted (or not inverted) depending on the value of the control signal.
    Type: Grant
    Filed: September 3, 1998
    Date of Patent: September 18, 2001
    Assignee: Micron Technology, Inc.
    Inventor: Robert D. Norman
  • Patent number: 6252791
    Abstract: A very small computer memory card is densely packed with a large number of flash EEPROM integrated circuit chips. A computer memory system provides for the ability to removably connect one or more of such cards with a common controller circuit that interfaces between the memory cards and a standard computer system bus. Alternately, each card can be provided with the necessary controller circuitry and thus is connectable directly to the computer system bus. An electronic system is described for a memory system and its controller within a single memory card. In a preferred physical arrangement, the cards utilize a main circuitry board with a plurality of sub-boards attached thereto on both sides, each sub-board carrying several integrated circuit chips.
    Type: Grant
    Filed: December 28, 1999
    Date of Patent: June 26, 2001
    Assignee: SanDisk Corporation
    Inventors: Robert F. Wallace, Robert D. Norman, Eliyahou Harari
  • Patent number: 6253277
    Abstract: A non-volatile memory system having a memory controller, an array of memory cells and a memory operation manager. The operation manager carries out memory program, read and erase operation upon receipt of program, read and erase instruction from the controller, typically over a system bus. The address block circuitry is provided in the manager which is capable of performing an memory operation on a single address or on multiple addresses depending upon the state of the address block circuitry as determined by the controller. Multiple addresses can be generated based upon a single address provided by the controller so that sectors of the memory can be programmed or read thereby simplifying memory operations and reducing the overhead of the memory controller.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: June 26, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Vinod C. Lakhani, Robert D. Norman, Christophe J. Chevallier
  • Publication number: 20010003837
    Abstract: A memory system having a memory controller and several separate memory devices connected to the controller by a system bus. The memory devices each included an array of memory cells, addressing circuitry used to address the cells and an address storage circuit which stores a local address unique to each of the memory devices. The local addresses are sequentially assigned to the memory devices by selecting a first one of the devices and forwarding an address assign command to the selected device. A command decoder, having detected the address assign command, will permit a local address placed on the bus by the controller to be loaded into the selected memory device. This sequence will continue until all of the memory devices have been assigned local addresses at which time the memory devices can be accessed to perform memory read, program, erase and other operations.
    Type: Application
    Filed: December 14, 2000
    Publication date: June 14, 2001
    Applicant: Micron Technology, Inc.
    Inventors: Robert D. Norman, Vinod C. Lakhani
  • Publication number: 20010002174
    Abstract: A system of Flash EEprom memory chips with controlling circuits serves as non-volatile memory such as that provided by magnetic disk drives. Improvements include selective multiple sector erase, in which any combinations of Flash sectors may be erased together. Selective sectors among the selected combination may also be de-selected during the erase operation. Another improvement is the ability to remap and replace defective cells with substitute cells. The remapping is performed automatically as soon as a defective cell is detected. When the number of defects in a Flash sector becomes large, the whole sector is remapped. Yet another improvement is the use of a write cache to reduce the number of writes to the Flash EEprom memory, thereby minimizing the stress to the device from undergoing too many write/erase cycling.
    Type: Application
    Filed: January 18, 2001
    Publication date: May 31, 2001
    Inventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
  • Patent number: 6230233
    Abstract: A mass storage system made of flash electrically erasable and programmable read only memory (“EEPROM”) cells organized into blocks, the blocks in turn being grouped into memory banks, is managed to even out the numbers of erase and rewrite cycles experienced by the memory banks in order to extend the service lifetime of the memory system. Since this type of memory cell becomes unusable after a finite number of erase and rewrite cycles, although in the tens of thousands of cycles, uneven use of the memory banks is avoided so that the entire memory does not become inoperative because one of its banks has reached its end of life while others of the banks are little used. Relative use of the memory banks is monitored and, in response to detection of uneven use, have their physical addresses periodically swapped for each other in order to even out their use over the lifetime of the memory.
    Type: Grant
    Filed: September 13, 1991
    Date of Patent: May 8, 2001
    Assignee: Sandisk Corporation
    Inventors: Karl M. J. Lofgren, Robert D. Norman, Gregory B. Thelin, Anil Gupta