摘要:
The present invention provides a new (ATD) address transition detection circuit for use on an address bus having any number of address lines. An ATD circuit is disclosed which comprises a first and second circuit and an interval timer. The first circuit has a first and second input and an output. The first circuit receives, at the first input, a change signal corresponding to transitions in one or more addresses of an address bus. In response, the output of the first circuit transitions from an initial first state to a second state. The first circuit is also responsive to a reset command at the second input to return the output to the first state. The interval timer has an output coupled to the second input of the first circuit and an input. The interval timer responsive to an initialize command at the input initiates a timed interval and after the timed interval generates the reset command at the output. The second circuit has an output coupled to the input of the interval timer and an input. The second circuit responsive to the change signal at the input generates an initialize command at the output. The circuit provides a second state at the output of the first circuit, for all including the last received in a series of change signals. This assures that all address transitions have been detected before a memory access is allowed.
摘要:
A user-programmable write protection scheme provides flexibility and superior write protect features for an integrated circuit memory which comprises an array of non-volatile erasable and programmable memory cells, including a plurality of sectors. Command logic detects command sequences indicating operations for the array, including a program operation, a sector erase operation, a read operation, a sector lock operation, and a sector unlock operation. The sector protect logic includes sector lock memory, including non-volatile memory cells that store sector lock signals for at least one sector in the array. Among other functions, the sector protect logic: 1) inhibits sector erase and program operations to a particular sector in response to a set sector lock signal corresponding to the particular sector, and to a first state of control signals in the set of control signals; 2) enables sector erase and program operations in response to a reset sector lock signal corresponding to the particular sector, and to the first state of control signals in the set of control signals; 3) inhibits sector erase and program operations to the particular sector independent of the sector lock signal in response to a second state of control signals in the set of control signals; and 4) enables sector erase and program operations independent of the sector lock signal in response to a third state of control signals in the set of control signals.
摘要:
The present invention discloses a regulator system (112) for regulating the output current and voltage (Vout) of a charge pump circuit (104). It is observed that the output current and voltage (Vout) of a charge pump circuit (104) can be regulated by varying the amplitude and frequency of a set of clock signals (modulated clocks). The present invention comprises means (decoders 1, 2; AM, FM units) for generating a set of control signals (VAD1-VFDn) as the function of the output current and voltage (Vout). The set of control signals (VAD1-VFDn) is coupled to a clock signal generation circuit (130) that generates a set of clock signals (modulated clocks) having a magnitude and a frequency depending on this set of at least one control signal. This set of clock signals (modulated clocks) is then used to drive the charge pump circuit (104). It is found that this regulator circuit (112) consumes less power than prior art regulator circuits.
摘要:
An on chip voltage generation circuit suitable for use on integrated circuits such as flash memory devices with a low power supply voltage (e.g., 2.7 to 3.6 volts) includes a sense circuit on the integrated circuit which generates an output indicating a level of the supply voltage. The on chip voltage supply circuit generates the on chip voltage in response to the output of the sense circuit and the supply voltage. The sense circuit output indicates the level of the supply voltage so that the on chip voltage supply circuit is able to adapt the amount of boosting utilized to produce the on chip voltage in response. The on chip voltage supply circuit generates the word line voltage at a node coupled to word line driving circuits in the device.
摘要:
A nonvolatile memory array is divided into multiple memory groups. The nonvolatile memory array receives an erase command to erase a first set of the memory groups, and not a second set of the memory groups. The control circuitry is responsive to the erase command to erase the first set of memory groups, by applying a recovery bias arrangement that adjusts threshold voltages of memory cells in at least one memory group of the second set of memory groups. By applying the recovery bias arrangement to memory cells in at least one memory group of the second set of memory groups, erase disturb is corrected during the recovery bias arrangement, at least in part.
摘要:
A nonvolatile memory array has a multiple erase procedures of different durations. A block of memory cells of the array can be erased by one of the different erase procedures.
摘要:
An integrated circuit memory device has a memory array and control logic with at least a first addressing mode in which the instruction includes a first instruction code and an address of a first length; and a second addressing mode in which the instruction includes the first instruction code and an address of a second length. The first length of the address is different from the second length of the address.
摘要:
A memory apparatus includes a host device and a slave device. The host device stores verification data. The slave device includes a memory unit, a control unit, and a logic unit. The control unit drives the memory unit to provide storage data in a data transmission sub-period, and further provides a control signal, indicating the first verification data, in a dummy sub-period. The logic unit provides first preamble data, indicating substantially a same data value as the verification data, in the dummy sub-period in response to the first control signal. The preamble data and the storage data are transmitted according to an internal clock signal. The host device samples the first preamble data according to an external clock signal, and determines whether the external and the internal clock signals are synchronized by comparing the first preamble data and the first verification data.
摘要:
Techniques are described herein for detecting and recovering over-erased memory cells in a flash memory device. In one embodiment, a flash memory device includes a memory array including a plurality of blocks of memory cells. The device also includes a command interface to receive a command from a source external to the memory device. The device also includes a controller including logic to perform a leakage-suppression process in response to the command. The leakage-suppression process includes performing a soft program operation to increase a threshold voltage of one or more over-erased memory cells in a given block of memory cells and establish an erased state.
摘要:
Over-erasure induced noise on a data line in a nonvolatile memory that couples into an adjacent data line is mitigated by using twisted data lines and differential sensing amplifiers. Noise coupled into data lines is compensated by similar noise coupled into reference data lines and cancelled in the differential sensing amplifiers.