Data Security Patents (Class 365/185.04)
  • Patent number: 7145799
    Abstract: An improved Flash memory device is described with a protection register lock bit erase enable circuit. A bond pad coupled to the lock bit erase enable circuit of the improved Flash memory is not bonded when the individual Flash memory chip wafer is packaged. This allows the memory manufacturer to access the bond pad and erase the lock bits while the chip is still in wafer form via a test card probe, but makes the lock bits effectively uneraseable when the chip wafer is packaged. This enables the memory chip manufacturer to enhance reliability and fault tolerance of the Flash memory device by thoroughly testing the lock bits and protection register functionality. Additionally, the lock bit erase enable circuit increases manufacturing flexibility by allowing the memory chip manufacturer to reprogram the protection register and lock bits in case of organizational changes or inadvertent or erroneous programming of the protection register.
    Type: Grant
    Filed: June 30, 2005
    Date of Patent: December 5, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Giovanni Naso, Pietro Piersimoni, Tommaso Vali
  • Patent number: 7142452
    Abstract: A method and system for storing secure data in a multi-time programmable, non-volatile electrically-alterable memory device are disclosed. Accordingly, in an embodiment, a memory device may include a data register with a fixed N-bit pattern, comparator logic, control logic, and an array of non-volatile electrically-alterable memory cells. Each memory cell includes a floating gate to store an electronic charge representing the logical state of the memory cell. The plurality of memory cells may be logically partitioned to include an N-bit secure lock and a plurality of memory cells for storing secure data. The random bit values stored in the N-bit secure lock are read, and compared with the fixed N-bit pattern stored in the data register. If the N-bit patterns do not match, the control logic allows the plurality of memory cells for storing secure data to be programmed with secure data.
    Type: Grant
    Filed: March 10, 2005
    Date of Patent: November 28, 2006
    Assignee: Virage Logic Corporation
    Inventor: Vipin Kumar Tiwari
  • Patent number: 7135886
    Abstract: The embodiments of the present invention relate to the general area of Field Programmable Gate Arrays and, in particular, to Field Programmable Gate Arrays (“FPGAs”) comprising memory cells with both volatile and nonvolatile properties, and the control and management of each portion to overcome the disadvantages of each individual technology. Some of the advantages of combining the two properties in a single FPGA are power reduction, shorter power-on time, configuration flexibility, instant-on logic capability, cost savings in system components including nonvolatile instant-on devices, configuration memories, and standard CMOS process. Furthermore, to optimize these and other advantages of the proposed architecture, additional apparatus and methods are presented to individually and collectively manage and control different parts of such hybrid FPGAs.
    Type: Grant
    Filed: September 20, 2004
    Date of Patent: November 14, 2006
    Assignee: KLP International, Ltd.
    Inventor: Guy Schlacter
  • Patent number: 7123511
    Abstract: A write protection mechanism may be implemented that is external to a non-volatile memory device and/or that is external to controller/s that interface with the non-volatile memory device, thus providing increased security over unauthorized and/or undesirable write cycles to the memory device. Write protection security may be further enhanced by providing a write protection control signal that is external to the non-volatile memory and attached memory controller/s, thus preventing accidental or intentional override.
    Type: Grant
    Filed: May 22, 2006
    Date of Patent: October 17, 2006
    Assignee: L-3 Integrated Systems Company
    Inventor: Russell D. Newell
  • Patent number: 7120053
    Abstract: A semiconductor integrated circuit device includes a main cell array, a fuse cell array, main cell word lines arranged at the main cell array, and fuse cell word lines arranged at the fuse cell array. The fuse cell word lines are formed in a same direction as a direction of the main cell word lines.
    Type: Grant
    Filed: January 12, 2005
    Date of Patent: October 10, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shigeru Atsumi, Masao Kuriyama, Akira Umezawa, Hironori Banba, Tadayuki Taura, Hidetoshi Saito
  • Patent number: 7106627
    Abstract: A memory cell array has a first and a second storage area. The first storage area has memory elements selected by an address signal. The second storage area has memory elements selected by a control signal. A control circuit has a fuse element. When the fuse element has been blown, the control circuit inhibits at least one of writing and erasing from being done on the second storage area.
    Type: Grant
    Filed: August 2, 2005
    Date of Patent: September 12, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Noboru Shibata, Tomoharu Tanaka
  • Patent number: 7102925
    Abstract: A flash memory device including a boot location select signal for selecting location of a boot region is generated by coding it in a CFI block, generated depending on the state of the OTP cell in the protection block, or generated by applying the power supply voltage or the ground voltage as a metal option. The bank select circuit needs not be modified even though location of the boot region is changed. It is thus possible to shorten development time, simplify a verification work and reduce the size of a chip.
    Type: Grant
    Filed: June 27, 2003
    Date of Patent: September 5, 2006
    Assignee: Hynix Semiconductor Inc.
    Inventor: Hyeok Kang
  • Patent number: 7092288
    Abstract: A non-volatile transistor memory array has individual cells with a current injector and a non-volatile memory transistor. Injector current gives rise to charged particles that can be stored in the memory transistor by tunneling. When a row of the array is activated by a word line, the active row has current injectors ready to operate if program line voltages are appropriate to cause charge storage in a memory cell, while a cell in an adjacent row be erased by charge being driven from a memory transistor. A series of conductive plates are arranged over the word line, with each plate having a pair of oppositely extending tangs, one causing programming of a cell in a first row and another causing erasing of a cell in another row.
    Type: Grant
    Filed: February 4, 2004
    Date of Patent: August 15, 2006
    Assignee: Atmel Corporation
    Inventor: Bohumil Lojek
  • Patent number: 7085158
    Abstract: A nonvolatile semiconductor memory device is provided, comprising a nonvolatile memory cell array which has a one-time programming region accessed in response to a first decoding signal and a normal region accessed in response to a second decoding signal. The device performs a read operation and a write operation. The device further comprises (a) a data write circuit writing data in the nonvolatile memory cell array in response to a write enable signal during the write operation; (b) a data read circuit reading data output from the nonvolatile memory cell array in response to a sense amplifier enable signal during the read operation; and (c) a control means activating the sense amplifier enable signal when the first decoding signal is generated and comparing data output from the data read circuit to generate the write enable signal during the write operation.
    Type: Grant
    Filed: February 26, 2004
    Date of Patent: August 1, 2006
    Assignee: Samsung Electronics, Co., Ltd.
    Inventors: Byung-Gil Jeon, Byung-Jun Min
  • Patent number: 7085155
    Abstract: An electronic device for securing the contents of data storage and processing elements. The device includes a security element and a phase-change element connected in a parallel arrangement. The security element is a three-terminal device, having an ON state and an OFF state which differ in resistance and regulate electronic access to the phase-change element by controlling the flow of electrical current applied to the parallel combination. In the ON state, the resistance of the security element is less than that of the phase-change element, thereby precluding a determination of the resistance of the phase-change element. In this PROTECT mode, the contents of the phase-change element are secured. In the OFF state, the resistance of the security element is greater than that of the phase-change material so that the resistance of the parallel combination approaches that of the phase-change element. In this READ mode, the resistance and information content of the phase-change element can be determined.
    Type: Grant
    Filed: February 10, 2004
    Date of Patent: August 1, 2006
    Assignee: Energy Conversion Devices, Inc.
    Inventors: Stanford R. Ovshinsky, Morrel H. Cohen
  • Patent number: 7072211
    Abstract: A write protection mechanism may be implemented that is external to a non-volatile memory device and/or that is external to controller/s that interface with the non-volatile memory device, thus providing increased security over unauthorized and/or undesirable write cycles to the memory device. Write protection security may be further enhanced by providing a write protection control signal that is external to the non-volatile memory and attached memory controller/s, thus preventing accidental or intentional override.
    Type: Grant
    Filed: May 19, 2004
    Date of Patent: July 4, 2006
    Assignee: L-3 Integrated Systems Company
    Inventor: Russell D. Newell
  • Patent number: 7068538
    Abstract: A memory circuit comprising a memory area for storing data, a non-volatile memory area for storing at least one identification code, and a pin for storing the identification code in the non-volatile memory area. The memory circuit further comprising a programmable register in which a programmable state is fixed, wherein the programmable state indicates if the identification code has been stored in the non-volatile memory area, and a logic module which blocks any subsequent changes to the identification code fixed in the non-volatile memory area in response to the programmable state in the programmable register indicating that the identification code has been stored in the non-volatile area. The invention also relates to an associated method. The invention is useful particularly to avoid fraudulent reprogramming of the area containing the identification code. The invention also relates to an associated method.
    Type: Grant
    Filed: August 18, 2004
    Date of Patent: June 27, 2006
    Assignee: STMicroelectronics, S.A.
    Inventor: Jean Devin
  • Patent number: 7046570
    Abstract: Programmable logic devices (PLDs) that can be repeatedly erased and reprogrammed, e.g., during the testing and/or design phases, and then converted to one-time programmable (OTP) devices on a permanent basis, and methods of converting a PLD to an OTP device. In some embodiments, only the erase function is disabled in the device. Because programming data cannot then be erased from the device, the addition of new programming data is very unlikely to yield an operable design. Therefore, the programming function is also effectively disabled. The programming function can be directly disabled in addition to or instead of the erase function, if desired. The erase and/or programming functions can be disabled, for example, by blowing one or more fuses included in the erase and/or programming circuitry of the PLD.
    Type: Grant
    Filed: June 2, 2004
    Date of Patent: May 16, 2006
    Assignee: Xilinx, Inc.
    Inventor: John R. Hubbard
  • Patent number: 7036005
    Abstract: An embodiment for modifying the contents of a revision identification register includes a revision identification register that is both readable and writable (the contents of the revision identification register are modifiable). A revision identification modification bit is also included. The contents of the revision identification register are only modifiable when the revision identification modification bit is set to indicate that writes to the revision identification register will be accepted.
    Type: Grant
    Filed: December 31, 2001
    Date of Patent: April 25, 2006
    Assignee: Intel Corporation
    Inventors: Rajeev K. Nalawadi, Faraz A. Siddiqi
  • Patent number: 7031188
    Abstract: A memory system includes a flash memory device and an interface device. The flash memory device includes a one-time programmable block where protection data information is stored in a predetermined region, and the interface device includes a register for storing one-time programmable lock status information to indicate whether the one-time programmable block is programmed. When a program/erase command is applied externally in a one-time programmable mode, the interface device having the one-time programmable lock status information indicates whether the one-time programmable block is programmed. If the one-time programmable lock status information indicates that the one-time programmable block is programmed, the interface device cuts off an external access to the one-time programmable block.
    Type: Grant
    Filed: November 15, 2004
    Date of Patent: April 18, 2006
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Chul-Ho Lee, Hyun-Duk Cho, Chang-Rae Kim
  • Patent number: 7020019
    Abstract: A memory purge system destructively purges the memory circuits of a memory device. The system includes a power supply for supplying a selectable voltage and current. Switching circuits electrically connect the power supply to the memory circuits of the memory device. A controller selects a voltage and current supplied by the power supply and activates the switching circuit to apply the voltage and current to the memory circuits. The controller determines whether the memory circuits have been destroyed by monitoring current flow into the memory circuits.
    Type: Grant
    Filed: August 6, 2004
    Date of Patent: March 28, 2006
    Assignee: SimpleTech, Inc.
    Inventors: Nader Salessi, Hosein Gazeri
  • Patent number: 7009879
    Abstract: A test terminal negation circuit comprises a switch circuit which receives a test signal from a test terminal and outputs it in an asserted state as it is or in a predetermined negated state to a test object circuit, a test signal control circuit which controls an output signal of the switch circuit to be asserted or negated, a test mode signal generation circuit which generates a test mode signal which asserts the output signal of the switch circuit, and a negating signal generation circuit which can output a negating signal for forcing the output signal of the switch circuit into negated state and comprises an electrically rewritable nonvolatile memory element. When the test signal control circuit receives the negating signal, it does not assert the output signal of the switch circuit even it receives the test mode signal.
    Type: Grant
    Filed: March 28, 2005
    Date of Patent: March 7, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Shuro Fukuhara
  • Patent number: 7006377
    Abstract: An apparatus and method for booting a NAND flash memory of a mobile terminal. The apparatus comprises a NAND flash memory, a synchronous dynamic random access memory (SDRAM), a main read only memory (ROM), a main control unit, and a sub-control unit. The NAND flash memory stores an application code necessary for execution of an additional function provided in the mobile terminal, and a secondary program loader (SPL) boot code for access to the application code. The SDRAM stores the SPL boot code and application code sent from the NAND flash memory. The main ROM stores code values for the booting of the NAND flash memory and an initial program loader (IPL) boot code for initial access to the NAND flash memory. The main control unit detects and outputs the IPL boot code from the main ROM in response to a reset signal inputted thereto and then outputs the reset signal.
    Type: Grant
    Filed: September 9, 2004
    Date of Patent: February 28, 2006
    Assignee: Samsung Electronics co., Ltd.
    Inventor: Hyuk Oh
  • Patent number: 6996005
    Abstract: The present invention provides a nonvolatile memory card in which a program is added, modified, changed, or the like by selecting arbitrary firmware on a flash memory from a plurality of pieces of firmware on flash memories. In a memory card, in addition to a program stored in a built-in ROM, firmware on flash memories as programs for adding, changing, modifying, or the like of a function such as a patch program are stored. Firmware on a flash memory which is desired to be made valid is set in a parameter sector or the like and is loaded into an external RAM, and the CPU of a control logic executes a process.
    Type: Grant
    Filed: November 26, 2003
    Date of Patent: February 7, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Makoto Mori, Seisuke Hirosawa, Atsushi Shikata
  • Patent number: 6996006
    Abstract: A memory mat is provided separately from a memory mat that is a normal memory area, and data therein cannot be read from the outside. In a page buffer, information input from the outside is stored. A comparing circuit compares security information stored in memory mat with information stored in page buffer, and the comparison result is output to the outside as a status. Even when unauthorized copying is performed, information in memory mat is not copied. Therefore, an external apparatus can easily determine whether or not the semiconductor memory is an unauthorized copy by referring to the status.
    Type: Grant
    Filed: June 23, 2004
    Date of Patent: February 7, 2006
    Assignees: Renesas Technology Corp., Renesas Solutions Corporation
    Inventors: Shinichi Ishimoto, Yoshikazu Miyawaki, Shinji Kawai, Atsushi Ohba
  • Patent number: 6990026
    Abstract: A CPU locks a memory card attached to a card mount with a password by a lock/unlock processing according to an access limit application program, and unlocks the lock based on a predetermined condition. The function to control the secrecy of data recorded on the card is thus improved.
    Type: Grant
    Filed: April 21, 2004
    Date of Patent: January 24, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hideki Yagi
  • Patent number: 6972993
    Abstract: An improved flash EEPROM memory-based storage subsystem includes one or more flash memory arrays, each with three data registers and a controller circuit. During a flash program operation, one data register is used to control the program operation, a second register is used to hold the target data value, and a third register is used to load the next sector's data. Subsequent to a flash program operation, a sector's data are read from a flash array into the first data register and compared to the target data stored in the second register. When the data is verified good, the data from the third register is copied into the first and second registers for the next program operation. This creates an improved performance system that doesn't suffer data transfer latency during program operations that require data verification after the program operation is complete. Alternate embodiments perform the comparison using two register implementations and a single register implementations.
    Type: Grant
    Filed: February 7, 2003
    Date of Patent: December 6, 2005
    Assignee: SanDisk Corporation
    Inventors: Kevin M. Conley, Daniel C. Guterman, Carlos J. Gonzalez
  • Patent number: 6969662
    Abstract: A semiconductor device, such as a memory device or radiation detector, is disclosed, in which data storage cells are formed on a substrate 13. Each of the data storage cells includes a field effect transistor having a source 18, drain 22 and gate 28, and a body arranged between the source and drain for storing electrical charge generated in the body. The magnitude of the net electrical charge in the body 22 can be adjusted by input signals applied to the transistor, and the adjustment of the net electrical charge by the input signals can be at least partially cancelled by applying electrical voltage signals between the gate 28 and the drain 22 and between the source 18 and the drain 22.
    Type: Grant
    Filed: June 5, 2002
    Date of Patent: November 29, 2005
    Inventors: Pierre Fazan, Serguei Okhonin
  • Patent number: 6970386
    Abstract: A method and apparatus are disclosed for detecting if a semiconductor circuit has been exposed to ultra-violet light. An ultra-violet light detection circuit detects exposure to ultra-violet light and will automatically activate a security violation signal. The security violation signal may optionally initiate a routine to clear sensitive data from memory or prevent the semiconductor circuit from further operation. The ultra-violet light detection circuit detects whether a semiconductor circuit has been exposed to ultra-violet light, for example, by employing a dedicated mini-array of non-volatile memory cells. At least two active bit lines, blprg and bler, are employed corresponding to program and erase, respectively. One of the bit lines is only programmable and the other bit line is only eraseable. Generally, all of the bits in the dedicated non-volatile memory array are initially in approximately the same state, which could be erased, programmed or somewhere in between.
    Type: Grant
    Filed: March 3, 2003
    Date of Patent: November 29, 2005
    Assignee: Emosyn America, Inc.
    Inventor: Shane C. Hollmer
  • Patent number: 6970381
    Abstract: A semiconductor memory in which the protection state of data in a nonvolatile memory can be changed quickly and which provides sufficient security. A volatile protection state specification section controls the protection state of data in the nonvolatile memory. A nonvolatile initial state store section determines the initial state of the protection state specification section.
    Type: Grant
    Filed: December 30, 2003
    Date of Patent: November 29, 2005
    Assignee: Fujitsu Limited
    Inventor: Daisuke Nakata
  • Patent number: 6963501
    Abstract: An aspect of the present invention provides a nonvolatile memory that includes a memory cell array including a data storage area to store a data, and a data invert flag storage area to store a data invert flag indicating whether or not the data is inverted. The memory cell array outputs selected data and a data invert flag related to the selected data. A state machine determines whether or not the number of memory cells to which a bias voltage is applied is equal to or greater than a predetermined number when writing data into the memory cell array. The state machine instructs a data controller to transfer inverted data and a data invert flag if it is equal to or greater than the predetermined number.
    Type: Grant
    Filed: March 15, 2004
    Date of Patent: November 8, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hitoshi Shiga
  • Patent number: 6956773
    Abstract: A circuit (115,145,150), for programming a non-volatile memory device (100) having a plurality of memory cells (105), includes a plurality of driving elements (115) each one for applying a program pulse to a selected memory cell to be programmed. The driving elements are suitable to be supplied by a power supply unit (120,125), and a control means (145,150) controls the driving elements (115). The control means (145,150) includes means (150,205) for determining a residual capacity of the power supply unit, and a selecting means (145) selectively enables the driving elements (115) according to the residual capacity. A method of programming, an integrated circuit, and a computer system are also disclosed.
    Type: Grant
    Filed: November 12, 2003
    Date of Patent: October 18, 2005
    Assignee: STMicroelectronics S.r.l.
    Inventors: Rino Micheloni, Roberto Ravasio
  • Patent number: 6950345
    Abstract: A nonvolatile semiconductor memory device with a function of executing a verify operation for write data that is input from outside includes a memory cell array including memory cells arranged in a matrix, and a password storage area for storing password data, an input buffer that receives data input from outside, a first retaining circuit that retains input password data or write data, which is input to the input buffer, a verify sense amplifier that detects, at a time of the verify operation, the password data that is read out of the password storage area or data that is read out of the memory cell array, and a coincidence determination circuit that determines whether the input password data coincides with the read-out password data, or determines whether the write data coincides with the read-out data.
    Type: Grant
    Filed: June 24, 2004
    Date of Patent: September 27, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Naoya Tokiwa
  • Patent number: 6947323
    Abstract: An improved Flash memory device is described with a protection register lock bit erase enable circuit. A bond pad coupled to the lock bit erase enable circuit of the improved Flash memory is not bonded when the individual Flash memory chip wafer is packaged. This allows the memory manufacturer to access the bond pad and erase the lock bits while the chip is still in wafer form via a test card probe, but makes the lock bits effectively uneraseable when the chip wafer is packaged. This enables the memory chip manufacturer to enhance reliability and fault tolerance of the Flash memory device by thoroughly testing the lock bits and protection register functionality. Additionally, the lock bit erase enable circuit increases manufacturing flexibility by allowing the memory chip manufacturer to reprogram the protection register and lock bits in case of organizational changes or inadvertent or erroneous programming of the protection register.
    Type: Grant
    Filed: October 31, 2003
    Date of Patent: September 20, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Giovanni Naso, Pietro Piersimoni, Tommaso Vali
  • Patent number: 6940764
    Abstract: A method and circuit for blocking unauthorized access to at least one memory cell in a semiconductor memory. The method includes providing a switch and/or a link which assumes an open state when access to the at least one memory cell is to be blocked; and coupling-a data line associated with the at least one memory cell to a constant voltage source in response to the switch or link assuming an open state.
    Type: Grant
    Filed: March 12, 2002
    Date of Patent: September 6, 2005
    Assignee: HRL Laboratories LLC
    Inventors: William M. Clark, Jr., James P. Baukus, Lap-Wai Chow
  • Patent number: 6937512
    Abstract: A memory cell array has a first and a second storage area. The first storage area has a plurality of memory elements selected by an address signal. The second storage area has a plurality of memory elements selected by a control signal. A control circuit has a fuse element. When the fuse element has been blown, the control circuit inhibits at least one of writing and erasing from being done on the second storage area.
    Type: Grant
    Filed: May 22, 2003
    Date of Patent: August 30, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Noboru Shibata, Tomoharu Tanaka
  • Patent number: 6937516
    Abstract: A semiconductor device, such as a memory device or radiation detector, is disclosed, in which data storage cells are formed on a substrate. Each of the data storage cells includes a field effect transistor having a source, drain, and gate, and a body arranged between the source and drain for storing electrical charge generated in the body. The magnitude of the net electrical charge in the body can be adjusted by input signals applied to the transistor, and the adjustment of the net electrical charge by the input signals can be at least partially cancelled by applying electrical voltage signals between the gate and the drain and between the source and the drain.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: August 30, 2005
    Assignee: Innovative Silicon S.A.
    Inventors: Pierre Fazan, Serguei Okhonin
  • Patent number: 6934186
    Abstract: A semiconductor device, such as a memory device or radiation detector, is disclosed, in which data storage cells are formed on a substrate. Each of the data storage cells includes a field effect transistor having a source, drain, and gate, and a body arranged between the source and drain for storing electrical charge generated in the body. The magnitude of the net electrical charge in the body can be adjusted by input signals applied to the transistor, and the adjustment of the net electrical charge by the input signals can be at least partially cancelled by applying electrical voltage signals between the gate and the drain and between the source and the drain.
    Type: Grant
    Filed: December 19, 2003
    Date of Patent: August 23, 2005
    Assignee: Innovative Silicon S.A.
    Inventors: Pierre Fazan, Serguei Okhonin
  • Patent number: 6930918
    Abstract: A semiconductor device, such as a memory device or radiation detector, is disclosed, in which data storage cells are formed on a substrate. Each of the data storage cells includes a field effect transistor having a source, drain, and gate, and a body arranged between the source and drain for storing electrical charge generated in the body. The magnitude of the net electrical charge in the body can be adjusted by input signals applied to the transistor, and the adjustment of the net electrical charge by the input signals can be at least partially cancelled by applying electrical voltage signals between the gate and the drain and between the source and the drain.
    Type: Grant
    Filed: December 1, 2003
    Date of Patent: August 16, 2005
    Assignee: Innovative Silicon S.A.
    Inventors: Pierre Fazan, Serguei Okhonin
  • Patent number: 6925006
    Abstract: A semiconductor device, such as a memory device or radiation detector, is disclosed, in which data storage cells are formed on a substrate. Each of the data storage cells includes a field effect transistor having a source, drain, and gate, and a body arranged between the source and drain for storing electrical charge generated in the body. The magnitude of the net electrical charge in the body can be adjusted by input signals applied to the transistor, and the adjustment of the net electrical charge by the input signals can be at least partially cancelled by applying electrical voltage signals between the gate and the drain and between the source and the drain.
    Type: Grant
    Filed: November 28, 2003
    Date of Patent: August 2, 2005
    Assignee: Innovative Silicon S.A.
    Inventors: Pierre Fazan, Serguei Okhonin
  • Patent number: 6906960
    Abstract: A semiconductor memory device includes: a plurality of banks with electrically rewritable memory cells arranged therein, the banks being configured to be simultaneously accessible in such a manner that a data write operation into a bank and a data read operation for another bank are simultaneously performed; a write-use data bus commonly disposed for the plurality of banks; a read-use data bus commonly disposed for the plurality of banks; a write circuit connected to the write-use data bus; a read circuit connected to the read-use data bus; a bank address decoder circuit for decoding external bank address signals for bank selecting to output internal bank address signals, the bank address decoder circuit having such an address conversion function that one of plural kinds of address conversions between the external bank address signals and the internal bank address signals is selectable; and a rewrite control circuit for sequence controlling a data write operation for a bank selected by the bank address decode
    Type: Grant
    Filed: March 10, 2003
    Date of Patent: June 14, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hidetoshi Saito, Hideo Kato, Tokumasa Hara
  • Patent number: 6898125
    Abstract: A semiconductor device has a memory cell array composed of a plurality of electrically rewritable nonvolatile memory cells and output disabling means for disabling data held in the memory cell array from being outputted to the outside. The output disabling means disables the outputting of the data when the power supply is turned ON and removes the disabling of the outputting of the data if a specified operational procedure is performed to the memory cell array.
    Type: Grant
    Filed: March 7, 2003
    Date of Patent: May 24, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Yoshiyuki Tanaka
  • Patent number: 6885607
    Abstract: Predetermined programs and data are written into a first flash memory. The first flash memory is divided into a plurality of blocks. Security information for the respective blocks of the first flash memory is written into a second flash memory. The security information indicates whether or not reading of the stored data to the outside from the respective blocks of the first flash memory is prohibited. When a read target address signal is output by a CPU, the corresponding read data is read from the first flash memory and supplied to the CPU and a tri-state buffer. As a result, the CPU is able to obtain desired input data. A security signal from the second flash memory is supplied to the control terminal of the tri-state buffer. Accordingly, if reading of data to the outside is prohibited, the read data is not transmitted to the outside.
    Type: Grant
    Filed: September 24, 2003
    Date of Patent: April 26, 2005
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Kazumasa Ozawa
  • Patent number: 6879518
    Abstract: A memory device having a memory array of nonvolatile memory elements also includes one or more security rows (or columns) of security bits that can be programmed to a locked status. External memory access requests are processed by first reading the corresponding security bit. If the requested row or column is locked, a default zero value is returned. Only external requests of unlocked locations, and all internal access requests, return the actual memory contents. Security bits can be erased (unlocked), but the secured contents of the locked row or column is also erased at the same time.
    Type: Grant
    Filed: November 21, 2003
    Date of Patent: April 12, 2005
    Assignee: Atmel Corporation
    Inventor: Duncan Curry
  • Patent number: 6874069
    Abstract: A single integrated circuit microcontroller 10 includes an embedded erasable/programmable non-volatile memory 12 having a read protection capability. Microcontroller 10 can operate within a special mode in which external circuits may access memory 12 by use of input/output pins 18. When microcontroller 10 activates this special mode, a read protection flag 13 within memory 12 is checked. The read protection flag 13 may be set during production of the microcontroller 10 after instructional data or firmware has been installed onto memory 12. If the read protection flag 13 has been set, only certain portions of the memory 12 may be read, depending upon the value of the read protection flag 13.
    Type: Grant
    Filed: July 26, 2002
    Date of Patent: March 29, 2005
    Assignee: Silicon Storage Technology, Inc.
    Inventors: Fong-Long Lin, Xiangyang Teng
  • Patent number: 6845040
    Abstract: A nonvolatile memory in which a rewrite disabled region may be set freely operates whereby an address signal is decoded by a row decoder, a selected word line is set at “H”, and this is transmitted to a high voltage application decoder. Information indicating whether the rewriting of a memory cell in a memory cell array is permitted or prohibited is set in a disablement information setting portion, and security signals are outputted for word line units. When a word line for which rewriting is permitted is selected, a latch inside the high voltage application decoder is set, and a high voltage for rewriting is outputted to the corresponding word line at the next rewrite timing. For word lines in which rewriting is prohibited, the latch is not set and the high voltage for rewriting is not outputted to the word lines.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: January 18, 2005
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Kenichi Watanabe
  • Patent number: 6842371
    Abstract: A master block lock control word is written to a mini array of non-volatile fuses. The control word is recalled and decoded. A successful recall of the control word generates an indication that the master block lock bit is permanently disabled from subsequent changes.
    Type: Grant
    Filed: June 3, 2003
    Date of Patent: January 11, 2005
    Assignee: Micron Technology, Inc.
    Inventor: Mitch Liu
  • Patent number: 6842373
    Abstract: Embodiments of the invention provide a command decoder and related circuitry for use in a semiconductor memory device that can operate both as a double rate synchronous dynamic random access random access memory device, and a fast cycle random access memory device.
    Type: Grant
    Filed: July 10, 2002
    Date of Patent: January 11, 2005
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: One-Gyun La, June-Bae Lee
  • Patent number: 6839277
    Abstract: A memory system includes manufacturer identifiers, such as serial numbers and part numbers, stored in locations of memory that are unalterable by end users. A customer identification location of the memory allows the user to program its own identifier and includes a locking code that prevents subsequent alteration of the customer identification location. A recall procedure at power on verifies the content of the locked code for allowing alteration of the memory.
    Type: Grant
    Filed: September 17, 2002
    Date of Patent: January 4, 2005
    Assignee: Silicon Storage Technology, Inc.
    Inventors: Hung Q. Nguyen, Loc B. Hoang
  • Patent number: 6836433
    Abstract: A rewrite disable control method for a non-volatile semiconductor storage device is disclosed for relying on a majority decision to determine whether a rewrite is disabled or enabled. A write disable control signal generating circuit reads three write disable flags of the same contents stored in security flag storage areas of three memory blocks, respectively, and makes a majority decision to determine a disable/enable state to establish the logic of a write disable control signal. Even if a power supply is instantaneously interrupted during an erasure of a certain block to cause a change in the security flag associated with one memory block, the security flags stored in the two remaining memory blocks maintain the original values, thereby making it possible to effectively prevent a trouble in which an unintended disable setting is validated.
    Type: Grant
    Filed: July 2, 2003
    Date of Patent: December 28, 2004
    Assignee: NEC Electronics Corporation
    Inventor: Takao Kondo
  • Patent number: 6826097
    Abstract: A nonvolatile memory device including a write protected region, comprising a program command processor, a write protected region setting unit and a write controller. The program command processor outputs a program command signal by decoding an external signal. The write protected region setting unit stores a region address corresponding to an inputted address when the program command signal is activated, and outputs a write protect signal when the program command signal is inactivated. The write controller controls a cell corresponding to the region address not to perform a write mode when the write protect signal is activated.
    Type: Grant
    Filed: June 30, 2003
    Date of Patent: November 30, 2004
    Assignee: Hynix Semiconductor Inc.
    Inventor: Hee Bok Kang
  • Publication number: 20040233714
    Abstract: A semiconductor memory device includes a control logic circuit for generating read selection signals each selecting one plane for reading and write selection signals each selecting one plane for writing from a plurality of planes in which memory cells are arranged in an array, an address selection circuit disposed for each of the planes, and an address buffer circuit for simultaneously providing a write address and a read address. Each of the address selection circuits is configured so as to be able to receive one of the read selection signals and one of the write selection signals from the control logic circuit.
    Type: Application
    Filed: May 20, 2004
    Publication date: November 25, 2004
    Inventors: Yoshinao Morikawa, Masaru Nawaki, Hiroshi Iwata, Akihide Shibata
  • Patent number: 6819622
    Abstract: A synchronous flash memory includes an array of non-volatile memory cells, and has a package configuration that is compatible with an SDRAM. The memory device includes a memory array, a programmable register circuitry to store protection data, and a voltage detector to determine if a memory power supply voltage drops below a predetermined level. Control circuitry is provided to program the register circuitry and prevent erase or write operations to the memory array in response to the voltage detector. In operation, the memory monitors a power supply voltage coupled to the memory, and prohibits write or erase operations from being performed if the supply voltage drops below a predetermined value.
    Type: Grant
    Filed: January 21, 2004
    Date of Patent: November 16, 2004
    Assignee: Micron Technology, Inc.
    Inventors: Frankie F. Roohparvar, Ebrahim Abedifard
  • Patent number: 6814297
    Abstract: The invention relates to a method and an arrangement for controlling access to EEPROMs' and to a corresponding computer software product and a corresponding computer-readable storage medium, which can in particular be used to prevent the unauthorized manipulation of EEPROMs. Specifically, it is possible by using the invention to stop the unauthorized use of totally erased EEPROMs on smart-card controllers. EEPROM fuses that, depending on the application, comprise one or more bits, are used in the continuing course of operation of a controller, to permit or forbid security-related functions. Provision is made as part of the invention for EEPROM fuses to be used to permit writing to the EEPROM only if said fuse comprises a given combination of bits. Any manipulation of this fuse, such as by erasing the entire matrix for example or else by manipulating the booting process, then bars all further write accesses to the EEPROM.
    Type: Grant
    Filed: December 16, 2002
    Date of Patent: November 9, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Detlef Mueller
  • Patent number: 6808169
    Abstract: A non-volatile memory (NVM) system includes a NVM cell having: a semiconductor region having a first conductivity type; a gate dielectric layer located over the semiconductor region; a gate electrode located over the gate dielectric layer; a source region and a drain region of a second conductivity type, opposite the first conductivity type, located in the semiconductor region and aligned with the gate electrode; a crown electrode having a base that contacts the gate electrode and walls that extend vertically from the base region, away from the gate electrode; a dielectric layer located over the crown electrode, wherein the dielectric layer extends over at least interior surfaces of the walls; and a plate electrode located over the dielectric layer, wherein the plate electrode extends over at least interior surfaces of the walls.
    Type: Grant
    Filed: September 6, 2001
    Date of Patent: October 26, 2004
    Assignee: Monolithic System Technology, Inc.
    Inventors: Fu-Chieh Hsu, Wingyu Leung