Abstract: According to one embodiment, one variable delay circuit adjusts a data strobe signal to be delayed, a control circuit generates an auxiliary signal, another variable delay circuit adjusts the auxiliary signal to be delayed, a mask generation circuit generates a mask signal based on the delayed data strobe signal and the delayed auxiliary signal, and an AND circuit applies the mask signal to the delayed data strobe signal, thereby generating a data strobe signal without a glitch. A write address signal generation circuit generates a control signal for controlling a flip-flop group based on the data strobe signal without the glitch, and the flip-flop group stores read data according to the control signal. A selector selects data from among pieces of data stored in the flip-flop group according to the read address signal.

Abstract: A redundancy system for disabling access to normal memory elements when memory addresses corresponding to those normal memory elements match programmed redundancy addresses before the memory addresses and the programmed redundancy addresses are compared. Access to the normal memory elements is disabled based on the programmed redundancy addresses.

Abstract: Methods of securing the erasing and/or programming or reprogramming of data and/or programs in a memory of a computer, in particular a control unit in a motor vehicle, are described. In programming, either an identifier that identifies correct erasing and/or programming of memory is entered into an area of memory that is to be erased and/or programmed or it is selected from the data and/or programs already entered, in particular from a program identifier in the form of a section from it. In addition, the identifier is altered in memory before erasing and/or programming the data and/or programs, in particular by erasing and/or programming, so that the respective memory contents are not used in the event of an interruption in the programming operation and thus in the event of defective programming.

Abstract: A method and apparatus for resetting and modifying special registers in a security token is described. In one embodiment, a register may be reset when a reset flag is true when a special transmission on a bus demonstrates the mutual locality of the associated processor and chipset. A modify flag may also be used to indicate whether the register contents may be modified. Modifications may also be dependent upon demonstration of mutual locality.

Abstract: A semiconductor device of this invention includes an initialization circuit for initializing a predetermined circuit in accordance with the level of a power source voltage, and a status setting unit for setting the status of the semiconductor device to “busy” during a period in which the initialization circuit performs initialization.

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.

Abstract: Various embodiments of a method and system for inhibiting reads to non-guaranteed data in remapped portions of a storage medium are disclosed. In one embodiment, a method of managing a non-read list associated with a storage medium involves: detecting a bad portion of the storage medium, remapping the bad portion's address to a new portion of the storage medium, copying the data stored to the bad portion to the new portion and, if the copy is unsuccessful, adding the address of the new portion to the non-read list, and inhibiting a read to the new portion if the new portion's address is listed on the non-read list. The address of the new portion may be removed from the non-read list in response to a successful write to the new portion.

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.

Abstract: In the Retirement Payload Array (RPA) of a microprocessor, the signal “READ” is logically combined with the primary clock signal “CLK” in a control circuit of a modified glitch latch such that the glitch latch will only reset, and therefore a reset edge or “glitch” will only appear, when new data is read and the signal IN will return to zero and allow the modified glitch latch to recover.

Abstract: Flash memory devices include at least one flash memory array and an address compare circuit that is configured to indicate whether an applied row address associated with a first operation (e.g., program, erase) is within or without an unlock area of the at least one flash memory array. A control circuit is also provided. This control circuit is configured to block performance of the first operation on the flash memory array in response to detecting an indication from the address compare circuit that the applied row address is outside the unlock area of the flash memory array.

Abstract: A semiconductor memory device wherein, in continuous data reading, a notification signal to notify whether a suspend mode is entered or not is given synchronously with data output control according to an output control signal with a suspend function, and a method of controlling the device. When an output enable signal is also used as a suspend instruction, a synchronizing circuit synchronizes the output enable signal with a clock signal to output a synchronized output enable signal. This synchronized output enable signal is supplied to a ready control circuit and an output buffer circuit so that the output control of data and ready signal is performed in synchronization with the clock signal. A data terminal goes into a high impedance state in synchronization with the clock signal, which notifies transition to the suspend mode. This quickly notifies that the system bus has become open.

Abstract: A random access memory comprises a plurality of data pads and an array of memory cells comprising a first portion of memory cells and a second portion of memory cells. The random access memory comprises a first line configured to receive first data signals between the first portion of memory cells and the data pads and a second line configured to receive second data signals between the second portion of memory cells and the data pads. The first portion of memory cells is configured to be made inaccessible to eliminate the first data signals and a first number of the data pads and the second portion of memory cells is configured to be made inaccessible to eliminate the second data signals and a second number of the data pads.

Abstract: The performance of digital signals depends to a great extent on the frequency. However, the higher the frequency, the shorter the remaining time, in which digital signals can be reliably received by a receiver from a driver via a printed conductor. The run time of the clock pulse and signals must be optimized in such a way that no timing losses occur at any location, even in the extreme environmental conditions. The invention improves the timing and minimizes external influences by coupling the output signals to an internal PLL clock pulse.

Abstract: A memory controller or other device may be programmed with a data mask mapping scheme. A selection device within the memory controller may be set with the data mask mapping scheme between data and a data mask. In one embodiment, a storage device may be included and programmed with the data mask mapping scheme.

Abstract: A memory device includes delay locked loop that generates an internal signal based on an external signal. The internal signal serves a reference clock signal for most modes operations of the memory device. In a self refresh mode, the delay locked loop is completely deactivated to completely deactivate the internal signal. In a non-self refresh mode, the delay locked loop is periodically deactivated to periodically deactivate the internal signal based on certain modes of operations of the memory device.

Abstract: A secure command is entered into a Flash memory device. A control data word is written to the memory device to specify which blocks of memory are to be permanently secured against write and erase operations. The bits of the control data word specify different blocks of memory to be permanently secured.

Abstract: According to one embodiment, an apparatus for detecting and preventing tampering with a programmable digital device. The apparatus comprises a one-time programmable (OTP) memory that includes a plurality of memory cells to store data. The plurality of memory cells may be programmed to a default state or a state opposite the default state. A tamper detection circuit is coupled to these memory cells in order to sense a condition when each bit associated with the plurality of memory cells is programmed to the state opposite the default state. In response to detecting this condition, it is considered that the programmable digital device implemented with the apparatus has been tampered with and operations are performed to combat the tampering of the digital device.

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.

Abstract: In a non-volatile memory, a programming cycle consists of the following phases: high voltage charging up, programming pulse, and discharge. The actual programming process only takes place in the programming pulse phase. Several break points are defined relative to elapsed time and introduced in the programming pulse phase. Upon receiving a suspend request, the programming operation will advance to the next break point, then discharge the high programming voltage and go to a suspend state. A separate counter is used to monitor the break points so that elapsed non-programming time can be deducted from the total programming pulse time when the programming operation is resumed. By doing so, the device can handle frequent suspend and resume requests. Since the total time duration in the programming pulse phase is equal for the programming operation with and without suspend and resume requests, the programming proceeds efficiently to completion.

Abstract: A sensor 2 of a data collection system 2 is designed to make, in a predetermined environment, an operation of writing output data of a sensing circuit 24 into a non-volatile memory 22 as reference-value data, and, in a measurement environment, an operation of transmitting output data of the sensing circuit and reference-value data stored in the non-volatile memory, under the control of a memory control section 25, thereby selectively performing by itself the data-writing or data-transmitting operation without receiving instructions from a readout device.

Abstract: A semiconductor integrated circuit device includes a memory, /CE transition detector, address transition detector, /WE transition detector and controller. The controller includes a timeout circuit. The timeout circuit generates an internal circuit control signal with preset width to control access to the memory based on detection results of the above transition detectors. The operation of the memory is controlled by the timeout circuit at the read time. The operation of the memory is controlled by the timeout circuit when transition of the end of a /WE signal is detected by the /WE transition detector before a timing specified by the timeout circuit at the write time. Further, the operation of the memory is controlled in response to the transition of the /WE signal when the transition of the end of the /WE signal is detected by the /WE transition detector after passage of the above timing.

Abstract: A method and system masking data being written to a memory device having a data bus. One method includes applying masking data on the data bus, storing the masking data in the memory device, applying write data on the data bus, storing the write data in the memory device, and applying the stored masking data to mask the stored write data.

Abstract: A semiconductor memory device is provided with a memory cell array including memory cells being arranged in a shape of matrix and requiring a refresh operation. In the semiconductor memory device, a control circuit controls a timing of the refresh operation in accordance with an internal signal independently of an external signal and controlling the memory cell array in a non-normal operation mode different from a normal operation mode for writing data into the memory cell array and reading out data from the memory cell array. The control circuit starts the non-normal operation mode in response to a sequence of entry into the non-normal operation mode based on a predetermined first command signal, sets the non-normal operation mode in response to a sequence of setting the non-normal operation mode based on a predetermined second command signal, and thereafter, executes operation of the corresponding non-normal operation mode which is set.

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.

Abstract: A semiconductor memory device capable of accelerating address access and shortening cycle time is provided. A first address decoder (2) and first refresh address decoder (5) respectively decode an external address (Xn) supplied from outside the semiconductor memory device and a refresh address (RXn) used for refreshing within the semiconductor memory device. A multiplexer (8) selects the external address side decode signal (XnDm) or the refresh address side decode signal (XnRm) and outputs the signal as a decode signal (XnMm) based on an external address transmission signal (EXTR) and refresh address transmission signal (RFTR) so that a refresh operation and a read/write operation is performed continuously within one memory cycle. A word driver (10) then decodes decode signals (XnMm, XpMq) selected with multiplexer (8) and so forth, and activates a word line (WLmq).

Abstract: A semiconductor memory device comprises memory cells, a bitline connected to the memory cells, a read circuit including a precharge circuit, and a first transistor connected between the bitline and the read circuit, wherein a first voltage is applied to a gate of the first transistor when the precharge circuit precharges the bitline, and a second voltage which is different from the first voltage is applied to the gate of the first transistor when the read circuit senses a change in a voltage of the bitline.

Abstract: A semiconductor memory device having a plurality of pair cells including a pair of cells for storing ordinary data and auxiliary data in which the operation of one cell in a pair cell can be checked. At normal operation time data can be read from or written to a desired cell by activating two word lines at a time. On the other hand, at operation test time data can be read from or written to only one cell in a pair cell by activating a desired word line.

Abstract: A refresh operation in a PSRAM device to hidden-refresh an internal memory cell by using a refresh pulse signal may be controlled by forming a dummy duration for the refresh operation in a read/write cycle, reducing the dummy duration when the refresh pulse signal is not generated, and delaying the read/write cycle until the refresh operation is completed, when the refresh pulse signal is generated. The dummy duration may be reduced by a given amount during a period in which the refresh operation is not being performed, while the dummy duration may be increased in period of time subject to the refresh operation.

Abstract: A method for controlling a semiconductor memory in which mode register can be set in burst mode. To set an operation mode in burst mode, the semiconductor memory is changed first from the burst mode, through power-down mode, to standby mode of non-burst mode. Then the semiconductor memory is changed to mode register set mode to set the mode register when commands are input in the same predetermined sequence that is used in the non-burst mode.

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.

Abstract: Methods and circuits for reducing unnecessary changes to outputs of latch circuits are provided. Unnecessary changes to outputs of latch circuits may be reduced by preventing the outputs of the latch circuits from changing when an invalid command is detected. For some embodiments, an invalid command detector is provided that generates an invalid command signal used to inhibit latch circuits, in response to detecting an invalid command.

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.

Abstract: Flash memory devices include at least one flash memory array and an address compare circuit that is configured to indicate whether an applied row address associated with a first operation (e.g., program, erase) is within or without an unlock area of the at least one flash memory array. A control circuit is also provided. This control circuit is configured to block performance of the first operation on the flash memory array in response to detecting an indication from the address compare circuit that the applied row address is outside the unlock area of the flash memory array.

Abstract: The present invention relates to a sense amplifier select circuit for use in a memory device consisting of cell arrays and sense amplifier arrays arranged in a shared sense amplifier mode. The sense amplifier select circuit includes a first control means for outputting a sense amplifier select signal in response to a block select signal and an operation control signal of a sense amplifier, and a second control means connected to the first control means to control the sense amplifier select signal, wherein the second control means applies an enable/disable signal when selection of a cell array is changed and keeps the enable/disable state when a sense amplifier to be sensed within a selected cell array is changed. As such, a corresponding cell array is continuously connected/disconnected to/from a bit line sense amplifier. As a result, it is possible to significantly reduce consumption of current occurring due to toggle of a sense amplifier select signal.

Abstract: The Disclosed is a method of reading a memory device in a page mode. The method includes the steps of inputting a row address for selecting the word line, enabling a corresponding word line by the row address, and reading/restoring the level of the cell node connected to the enabled word line, and disabling the enabled word line and sequentially enabling bit line sense amplifiers connected to the disabled word line to perform a read operation, wherein the disabling of the selected word line is performed after a lapse of a certain time period as much as data of a first cell node can be restored. Therefore, it is possible to reduce current consumption in a read operation of a page mode.

Abstract: A digital data processing system minimizes overall power consumption in a system having embedding large capacity RAMs. Power consumption is reduced by establishing sufficient set-up times when driving plural RAM blocks that have been held in a standby state. A RAM access controller is interposed between an oscillator and the RAM blocks, and controls a master clock generated from the oscillator to secure setup times of the RAM blocks.

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.

Abstract: Improved semiconductor integrated circuit random access memory (RAM) features pin-compatible replacement of SRAM devices, while providing low power and high density characteristics of DRAM devices. The refresh operations of a DRAM array are hidden so as to faithfully emulate an SRAM-type interface. The new refresh strategy is based on prohibiting the start of a refresh operation during certain periods but otherwise continuously refreshing the array, rather than affirmatively scheduling refresh at certain times as in the prior art. Short refresh operations are initiated frequently, driven by an internal clock that generates periodic refresh requests, except when a read or write operation is actually accessing the memory array. By isolating the DRAM memory array from I/O structures, external memory accesses are essentially interleaved with refresh operations, rather than temporally segregating them as in prior art.

Abstract: A nonvolatile memory circuit, comprises: memory regions, which contain N (N is a plurality) of the sectors, N not being an exponentiated number of two and the sectors having the same capacity; a sector selection circuit for decoding a sector address and selecting the sector which corresponds to the sector address; and a memory control circuit which, in response to an erase command, executes an erase operation to the selected sector and, upon verifying that the erasure is complete, sequentially changes said sector address to select the next sector. When a sector that does not exist in the memory regions is selected, said memory control circuit selects the next sector without performing an erase operation to the nonexistent sector.

Abstract: A semiconductor chip is provided, with which presence of dead pins can be easily noticed and a process for controlling the potential at dead pins can be performed easily. An input/output controller (IOC) for coordinating the input/output of signals through individual pins (PN1 to PN8) includes an input/output buffer (BFa) and the input/output buffer (BFa) includes a switch (SW4a) and a switch (SW4b). A setting memory (STMa) for storing settings for control of the input/output of signals in the input/output buffer (BFa) contains a memory table and the memory table contains an item about the dead pin potential control process so that a power-supply potential (Vdd) or a ground potential (GND) can be applied to the dead pins, i.e. the fourth pin (PN4) and the fifth pin (PN4).

Abstract: In a semiconductor memory incorporating therein a circuit for relieving a defective memory cell, a memory cell array constituted of a number of main memory cells MC00 to MCij is added with one column of redundant memory cells MC0j+1 to MCij+1 and one word line of substitution information storing memory cells MCRA0 to MCRAj+1. In only a first cycle after the power supply is turned on, the substitution information DR0 to DRj is read out from the substitution information storing memory cells by use of a writing/reading circuit associated with the main memory cells, and is transferred to and held in a control circuit. In a second and succeeding cycles, the control circuit generates Y selection circuit control signals CS0 to CSj on the basis of the substitution information held in the control circuit, and a Y selection circuit is controlled by the control signals CS0 to CSj so as to selectively connect the columns other than a defective column to an input/output line.

Abstract: A data strobe circuit for prefetching M number of N bit data, N and M being a positive integer, includes a data strobe buffering unit for generating N number of align control signals based on a data strobe signal; a synchronizing block having M number of latch blocks, each for receiving N bit data and outputting the N−1 bit data in a parallel fashion in response to N−1 number of the align control signals and one bit prefetched data in response to the remaining align control signals; and a output block having M number of aligning blocks, each for receiving the N−1 bit data in the parallel fashion, synchronizing the N−1 bit data with the align control signal and outputting the synchronized N−1 bit data as the N−1 bit prefetched data.

Abstract: A semiconductor memory device for easily and accurately evaluating a device. The memory device has a first access mode and a second access mode. The memory device includes an entry signal generation circuit to synthesize input signals and generate a first entry signal used to enter the first access mode. A control circuit generates a first mode trigger signal in response to the first entry signal. The control circuit also receives a second entry signal used to enter the second access mode and generates a second mode trigger signal in response to the second entry signal. The entry signal generation circuit logically synthesizes the input signals in a selective manner in accordance with a selection control signal to generate the first entry signal.

Abstract: A flash programmable microprocessor-based control module is operated in a manner to protect the integrity of event data stored in the programmable memory of the module while permitting authorized manufacturing and field alteration of the programmable memory with a Download and Execute routine. The Download and Execute routine is resident in a designated sector of the module's read-only memory, and download access to the module's random access memory after module manufacture has been completed is denied. During manufacture of the module, and during field programming of the controller prior to the writing of event data, the programmable memory may be externally altered by an authorized service tool by transferring the Download and Execute routine from read-only memory to random access memory for execution by the module's microprocessor, and downloading the new data or code over a data link coupling the service tool to the module.

Abstract: In a memory controller, a serial data including an instruction bit train with addition of a start bit, a clock signal, a chip enable signal, and a reset signal are inputted. During the active period in which the chip enable signal is being inputted, the serial data is stored depending on the clock signal and an enabling signal is generated based on the end timing of active period. Thereby, memory access is executed depending on contents of the instruction bit train. However, when the relevant apparatus is reset during the active period, generation of the enabling signal based on the end timing of the active period is inhibited.

Abstract: There are provided a semiconductor memory device and a refresh control method thereof to realize a refresh operation without any problem for external accesses while realizing low current dissipation operations for executing the refresh operation in separation from external access operation, in which the refresh operation is inhibited during execution of the external accesses. During this period, the internal operation in the refresh operation is controlled for the first refresh-operation-start request, but the internal operation for the second and subsequent refresh operation start requests is inhibited. Even when a plurality of refresh-operation-start requests are outputted previously while the refresh operation is inhibited during the external access operation, only the internal operation is not executed previously and the refresh operations after completion of the external access operation can surely be executed.

Abstract: A semiconductor memory with wordline timing, which links activating a wordline to an isolation signal. The isolation signal is applied to a memory section adjacent the memory section containing the wordline to be activated. Upon such an isolation signal shifting low and isolating the adjacent memory section, a timing circuit triggers a wordline decoder to activate a select wordline. The timing circuit prevents activation of the wordline decoder until the isolation signal is received.

Abstract: An auto precharge apparatus having an auto precharge gapless function protecting circuit in a semiconductor memory device which can prevent an externally-inputted illegal command from being executed, by disabling a row active peri signal earlier than a row active core signal in an auto precharge operation.

Abstract: In a memory controller for use with a DDR SDRAM, an apparatus improves the immunity of the controller to noise glitches on the DQS signal provided by the DDR SDRAM during READ operations. A method adjusts the noise immunity provided by the apparatus. In particular DQS quality circuits frame the DQS signal for a predetermined portion of the READ operation.

Abstract: A DRAM includes a set of secondary sense amplifiers as well as primary sense amplifiers coupled to respective digit lines of a DRAM array. The secondary sense amplifiers are coupled to the digit lines of an array through isolation transistors so that the secondary sense amplifier can be selectively isolated from the digit lines of an array. The DRAM also includes a refresh controller that periodically refreshes the DRAM on a row-by-row basis, and a command decoder that causes the refresh to be aborted in the even a read or a write command is received by the DRAM during a refresh. The refresh is aborted by saving the data stored in the row being refreshed in the secondary sense amplifiers and then isolating the sense amplifiers from the array. The memory access is then implemented in a normal manner. Since the DRAM can be accessed without waiting for the completion of a refresh in progress, the DRAM can be used as a cache memory in a computer system.