Patent classifications
G11C11/1677
Pulse programming techniques for voltage-controlled magnetoresistive tunnel junction (MTJ)
A method of programming a voltage-controlled magnetoresistive tunnel junction (MTJ) includes applying a programming voltage pulse (Vp), reading the voltage-controlled MTJ, and determining if the voltage-controlled MTJ is programmed to a desired state and if not, changing the Vp and repeating the applying and reading steps until the voltage-controlled MTJ is programmed to the desired state.
Memory devices with improved refreshing operation
A method and a system for memory cell programming and erasing with refreshing operation are disclosed. The system includes a selecting module, a processing module and a refresh module. In the method, at first, a target memory cell from a plurality of memory cells in a memory device is selected. Thereafter, the target memory cell belonging to a line of the matrix is programmed or erased by applying a selecting voltage on the target memory cell and a location-related memory cell belonging to the line of the matrix. Then, a refreshing operation to refresh the location-related cell is performed.
Resistive memory device and method of programming the same
A semiconductor memory device contains a first memory cell including a first variable resistive element, and a first circuit for controlling a write performed for the first memory cell. The first circuit performs a first write for writing first data in the first memory cell in a first time, determines whether the first write fails or not, and performs a second write for writing the first data in the first memory cell in a second time longer than the first time, if the first write fails.
MAGNETIC STORAGE DEVICE AND CONTROL METHOD OF MAGNETIC STORAGE DEVICE
According to one embodiment, a magnetic storage device includes a nonvolatile magnetic memory including a magnetoresistance effect element capable of storing data. A magnetic sensor is configured to measure the magnitude of an external magnetic field. A controller is configured to detect errors in the data at first time intervals when the measured magnitude of the external magnetic field is less than a threshold value and to detect errors in the data at second time intervals shorter than the first time interval when the measured magnitude of the external magnetic field is equal to or greater than the threshold value.
MEMORY ARRAY TEST METHOD AND SYSTEM
A method of testing a non-volatile memory (NVM) array includes heating the NVM array to a target temperature. While the NVM array is heated to the target temperature, a current distribution is obtained by measuring a plurality of currents of a subset of NVM cells of the NVM array, each NVM cell of the NVM array is programmed to one of a logically high state or a logically low state, and first and second pass/fail (P/F) tests on each NVM cell of the NVM array are performed. A bit error rate is calculated based on the current distribution and the first and second P/F tests.
MEMORY DEVICE WITH ON-CHIP SACRIFICIAL MEMORY CELLS
An integrated circuit includes a primary memory array with cells switchable between first and second states. The circuit also includes sacrificial memory cells; each fabricated to be switchable between the first and second states and associated with at least one row of the primary array. A controller is configured to detect a write operation to a row of the primary array, stress a sacrificial cell associated with the row and detect a failure of the associated sacrificial cell. The sacrificial cells are fabricated to have lower write-cycle endurance than cells of the primary array or are subjected to more stress. Failure of a row of the primary array is predicted based, at least in part, on a detected failure of the associated sacrificial cell.
Ramp Write Techniques
Various implementations described herein are related to a method. The method may apply a write control voltage to a bitcell. The method may gradually ramp the write control voltage to the bitcell. The method may terminate application of the write control voltage to the bitcell when a write operation is sensed in the bitcell.
Memory device for write operation including verification and operating method thereof
A memory device includes: a cell array including a memory cell and a reference cell; a sense amplifier configured to sense a difference between a first current flowing through the memory cell and a second current flowing through the reference cell, based on an activated sense enable signal; a controller configured to inactivate the sense enable signal in a program interval and activate the sense enable signal in a verify interval subsequent to the program interval, during a write operation; and a voltage driver configured to provide a write voltage to the memory cell in the program interval and the verify interval during the write operation, and to provide a read voltage to the memory cell during a read operation.
METHOD FOR WRITING TO MAGNETIC RANDOM ACCESS MEMORY
A method of manufacturing an array of magnetic random access memory cells includes writing to a magnetic random access memory cell. The writing to a memory cell includes determining an optimum write current for the array of memory cells, and applying the optimum write current to a first memory cell in the array. A first read current is applied to the first memory cell to determine whether a magnetic orientation of the first memory cell has changed in response to applying the optimum write current. A second write current is applied to the first memory cell when the magnetic orientation of the first memory cell has not changed. The second write current is different from the optimum write current. A second read current is applied to the first memory cell to determine whether the magnetic orientation of the first memory cell changed in response to applying the second write current.
MRAM access coordination systems and methods with a plurality of pipelines
Embodiments of the present invention facilitate efficient and effective increased memory cell density configuration. In one embodiment, a memory system comprises: an array of addressable memory cells, wherein the addressable memory cells of the array comprise magnetic random access memory (MRAM) cells and wherein further the array is organized into a plurality of banks; an engine configured to control access to the addressable memory cells organized into the plurality of banks; and a pipeline configured to perform access control and communication operations between the engine and the array of addressable memory cells. At least a portion of operations associated with accessing at least a portion of one of the plurality of memory banks via the pipeline are performed substantially concurrently or in parallel with at least a portion of operations associated with accessing at least another portion of one of the plurality of memory banks via the pipeline.