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).
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Publication number: 20030014689Abstract: 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: ApplicationFiled: September 6, 2002Publication date: January 16, 2003Inventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
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Patent number: 6462992Abstract: 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: GrantFiled: January 18, 2001Date of Patent: October 8, 2002Assignee: SanDisk CorporationInventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
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Patent number: 6434034Abstract: 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: GrantFiled: June 22, 2001Date of Patent: August 13, 2002Assignee: SanDisk CorporationInventors: Robert F. Wallace, Robert D. Norman, Eliyahou Harari
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Patent number: 6396729Abstract: 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: GrantFiled: November 13, 2000Date of Patent: May 28, 2002Assignee: Micron Technology, Inc.Inventors: Robert D. Norman, Vinod C. Lakhani, Christophe J. Chevallier
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Publication number: 20020046318Abstract: 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: ApplicationFiled: October 30, 2001Publication date: April 18, 2002Inventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotta
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Patent number: 6373747Abstract: 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: GrantFiled: April 14, 1998Date of Patent: April 16, 2002Assignee: SanDisk CorporationInventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
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Patent number: 6363454Abstract: 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: GrantFiled: April 18, 2000Date of Patent: March 26, 2002Assignee: Micron Technology, Inc.Inventors: Vinod C. Lakhani, Robert D. Norman, Christophe J. Chevallier
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Publication number: 20020032843Abstract: 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: ApplicationFiled: August 22, 2001Publication date: March 14, 2002Inventors: Karl M. J. Lofgren, Jeffrey Donald Stai, Anil Gupta, Robert D. Norman, Sanjay Mehrotra
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Patent number: 6353571Abstract: 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: GrantFiled: November 13, 2000Date of Patent: March 5, 2002Assignee: Micron Technology, Inc.Inventors: Robert D. Norman, Vinod C. Lakhani, Christophe J. Chevallier
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Publication number: 20020002653Abstract: 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: ApplicationFiled: May 11, 2001Publication date: January 3, 2002Applicant: Micron Technology, Inc.Inventors: Vinod C. Lakhani, Robert D. Norman, Christophe J. Chevallier
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Patent number: 6320815Abstract: 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: GrantFiled: November 13, 2000Date of Patent: November 20, 2001Assignee: Micron Technology, Inc.Inventors: Robert D. Norman, Vinod C. Lakhani, Christophe J. Chevallier
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Patent number: 6317812Abstract: 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: GrantFiled: September 8, 2000Date of Patent: November 13, 2001Inventors: Karl M. J. Lofgren, Jeffrey Donald Stai, Anil Gupta, Robert D. Norman, Sanjay Mehrotra
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Publication number: 20010026472Abstract: 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: ApplicationFiled: May 30, 2001Publication date: October 4, 2001Inventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
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Publication number: 20010024386Abstract: 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: ApplicationFiled: February 14, 2001Publication date: September 27, 2001Applicant: SanDisk CorporationInventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
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Patent number: 6292868Abstract: 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: GrantFiled: September 3, 1998Date of Patent: September 18, 2001Assignee: Micron Technology, Inc.Inventor: Robert D. Norman
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Patent number: 6252791Abstract: 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: GrantFiled: December 28, 1999Date of Patent: June 26, 2001Assignee: SanDisk CorporationInventors: Robert F. Wallace, Robert D. Norman, Eliyahou Harari
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Patent number: 6253277Abstract: 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: GrantFiled: September 2, 1999Date of Patent: June 26, 2001Assignee: Micron Technology, Inc.Inventors: Vinod C. Lakhani, Robert D. Norman, Christophe J. Chevallier
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Publication number: 20010003837Abstract: 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: ApplicationFiled: December 14, 2000Publication date: June 14, 2001Applicant: Micron Technology, Inc.Inventors: Robert D. Norman, Vinod C. Lakhani
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Publication number: 20010002174Abstract: 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: ApplicationFiled: January 18, 2001Publication date: May 31, 2001Inventors: Eliyahou Harari, Robert D. Norman, Sanjay Mehrotra
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Patent number: 6230233Abstract: 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: GrantFiled: September 13, 1991Date of Patent: May 8, 2001Assignee: Sandisk CorporationInventors: Karl M. J. Lofgren, Robert D. Norman, Gregory B. Thelin, Anil Gupta