Patent application number | Description | Published |
20100034009 | Asymmetric Write Current Compensation Using Gate Overdrive for Resistive Sense Memory Cells - Apparatus and associated method for asymmetric write current compensation for resistive sense memory (RSM) cells, such as but not limited to spin-torque transfer random access memory (STRAM) or resistive random access memory (RRAM) cells. In accordance with some embodiments, an RSM cell includes an RSM element coupled to a switching device. The switching device has a plurality of terminals. A control circuit compensates for asymmetric write characteristics of the RSM cell by limiting a range of voltage differentials across the terminals so as to be equal to or less than a magnitude of a source voltage applied to the switching device, thereby providing bi-directional write currents of substantially equal magnitude through the RSM element. | 02-11-2010 |
20100080071 | DATA STORAGE USING READ-MASK-WRITE OPERATION - Method and apparatus for writing data to a storage array, such as but not limited to an STRAM or RRAM memory array, using a read-mask-write operation. In accordance with various embodiments, a first bit pattern stored in a plurality of memory cells is read. A second bit pattern is stored to the plurality of memory cells by applying a mask to selectively write only those cells of said plurality corresponding to different bit values between the first and second bit patterns. | 04-01-2010 |
20100085795 | Asymmetric Write Current Compensation - An apparatus and method for compensating for asymmetric write current in a non-volatile unit cell. The unit cell comprises a switching device and an asymmetric resistive sense element (RSE), such as an asymmetric resistive random access memory (RRAM) element or an asymmetric spin-torque transfer random access memory (STRAM) element. The RSE is physically oriented within the unit cell relative to the switching device such that a hard direction for programming the RSE is aligned with an easy direction of programming the unit cell, and an easy direction for programming the RSE is aligned with a hard direction for programming the unit cell. | 04-08-2010 |
20100091548 | Non-Volatile Memory Array with Resistive Sense Element Block Erase and Uni-Directional Write - A non-volatile memory cell and associated method of use are disclosed. In accordance with various embodiments, the memory cell includes a switching device and a resistive sense element (RSE) connected in series between first and second control lines. The first control line is supplied with a variable voltage and the second control line is maintained at a fixed reference voltage. A first resistive state of the RSE is programmed by lowering the variable voltage of the first control line below the fixed reference voltage of the second control line to flow a body-drain current through the switching device. A different, second resistive state of the RSE is programmed by raising the variable voltage of the first control line above the fixed reference voltage to flow a drain-source current through the switching device. | 04-15-2010 |
20100097841 | Multi-Stage Parallel Data Transfer - Apparatus and associated method for transferring data to memory, such as resistive sense memory (RSM). In accordance with some embodiments, input data comprising a sequence of logical states are transferred to a block of memory by concurrently writing a first logical state from the sequence to each of a first plurality of unit cells during a first write step, and concurrently writing a second logical state from the sequence to each of a second non-overlapping plurality of unit cells during a second write step. | 04-22-2010 |
20100097852 | MRAM DIODE ARRAY AND ACCESS METHOD - A memory unit includes a magnetic tunnel junction data cell is electrically coupled to a bit line and a source line. The magnetic tunnel junction data cell is configured to switch between a high resistance state and a low resistance state by passing a write current through the magnetic tunnel junction data cell. A first diode is electrically between the magnetic tunnel junction data cell and the source line and a second diode is electrically between the magnetic tunnel junction data cell and the source line. The first diode and second diode are in parallel electrical connection, and having opposing forward bias directions. | 04-22-2010 |
20100110784 | STRAM with Self-Reference Read Scheme - Self-reference reading a magnetic tunnel junction data cell methods are disclosed. An illustrative method includes applying a read voltage across a magnetic tunnel junction data cell and forming a read current. The magnetic tunnel junction data cell has a first resistance state. The read voltage is sufficient to switch the magnetic tunnel junction data cell resistance. The method includes detecting the read current and determining if the read current remains constant during the applying step. If the read current remains constant during the applying step, then the first resistance state of the magnetic tunnel junction data cell is the resistance state that the read voltage was sufficient to switch the magnetic tunnel junction data cell to. | 05-06-2010 |
20100117160 | POLARITY DEPENDENT SWITCH FOR RESISTIVE SENSE MEMORY - Polarity dependent switches for resistive sense memory are described. A memory unit includes a resistive sense memory cell configured to switch between a high resistance state and a low resistance state upon passing a current through the resistive sense memory cell and a semiconductor transistor in electrical connection with the resistive sense memory cell. The semiconductor transistor includes a gate element formed on a substrate. The semiconductor transistor includes a source contact and a bit contact. The gate element electrically connects the source contact and the bit contact. The resistive sense memory cell electrically connects to the bit contact. The source contact and the bit contact are asymmetrically implanted with dopant material. | 05-13-2010 |
20100118587 | RESISTIVE SENSE MEMORY ARRAY WITH PARTIAL BLOCK UPDATE CAPABILITY - Various embodiments of the present invention are generally directed to a method and apparatus for carrying out a partial block update operation upon a resistive sense memory (RSM) array, such as formed from STRAM or RRAM cells. The RSM array is arranged into multi-cell blocks (sectors), each block having a physical block address (PBA). A first set of user data is written to a selected block at a first PBA. A partial block update operation is performed by writing a second set of user data to a second block at a second PBA, the second set of user data updating a portion of the first set of user data in the first PBA. The first and second blocks are thereafter read to retrieve the second set of user data and a remaining portion of the first set of user data. | 05-13-2010 |
20100118589 | Non-Volatile Memory Cell with Multiple Resistive Sense Elements Sharing a Common Switching Device - A non-volatile memory cell array and associated method of use are disclosed. In accordance with various embodiments, the array includes a plurality of programmable resistive sense elements (RSEs) coupled to a shared switching device. The switching device has a common source region and multiple drain regions, each drain region connected to an associated RSE from said plurality of RSEs. | 05-13-2010 |
20100118590 | Bidirectional Non-Volatile Memory Array Architecture - A bidirectional memory array architecture for non-volatile memory is disclosed. In accordance with some embodiments, a plurality of memory cells are arranged into an M number of rows and an N number of columns with each memory cell having a resistive sense element (RSE) and a switching device. A total number of M+N+1 control lines extend adjacent to and are connected with the memory cells to facilitate bi-directional programming of resistive states to each memory cell. | 05-13-2010 |
20100124095 | Floating Source Line Architecture for Non-Volatile Memory - A method and apparatus for writing data to a non-volatile memory cell, such as an RRAM memory cell. In some embodiments, a semiconductor array of non-volatile memory cells comprises a resistive sense element (RSE) and a switching device. A RSE of a plurality of memory cells is connected to a bit line while the switching device of a plurality of memory cells is connected to a word line and operated to select a memory cell. A source line is connected to the switching device and connects a series of memory cells together. Further, a driver circuit is connected to the bit line and writes a selected RSE of a selected source line to a selected resistive state by passing a write current along a write current path that passes through the selected RSE and through at least a portion of the remaining RSE connected to the selected source line. | 05-20-2010 |
20100135072 | Spin-Torque Bit Cell With Unpinned Reference Layer and Unidirectional Write Current - Method and apparatus for using a uni-directional write current to store different logic states in a non-volatile memory cell, such as a modified STRAM cell. In some embodiments, the memory cell has an unpinned ferromagnetic reference layer adjacent a cladded conductor, a ferromagnetic storage layer and a tunneling barrier between the reference layer and the storage layer. Passage of a current along the cladded conductor induces a selected magnetic orientation in the reference layer, which is transferred through the tunneling barrier for storage by the storage layer. Further, the orientation of the applying step is provided by a cladding layer adjacent a conductor along which a current is passed and the current induces a magnetic field in the cladding layer of the selected magnetic orientation. | 06-03-2010 |
20100174766 | Magnetic Precession Based True Random Number Generator - A method and apparatus for generating a random logic bit value. In some embodiments, a spin polarized current is created by flowing a pulse current through a spin polarizing material. The spin polarized current is injected in a free layer of a magnetic tunneling junction and a random logical bit value results from a variation in pulse current duration or a variation in thermal properties. | 07-08-2010 |
20100177551 | BIT SET MODES FOR A RESISTIVE SENSE MEMORY CELL ARRAY - Various embodiments of the present invention are generally directed to a method and apparatus for providing different bit set modes for a resistive sense memory (RSM) array, such as a spin-torque transfer random access memory (STRAM) or resistive random access memory (RRAM) array. In accordance with some embodiments, a group of RSM cells in a non-volatile semiconductor memory array is identified for application of a bit set operation. A bit set value is selected from a plurality of bit set values each separately writable to the RSM cells to place said cells in a selected resistive state. The selected bit set value is thereafter written to at least a portion of the RSM cells in the identified group. | 07-15-2010 |
20100177552 | TABLE-BASED REFERENCE VOLTAGE CHARACTERIZATION SCHEME - Method and apparatus for reading data from a non-volatile memory cell, such as a modified STRAM cell. In some embodiments, at least a first and second memory cell are read for a plurality of resistance values that are used to select and store a voltage reference for each memory cell. | 07-15-2010 |
20100177554 | BIPOLAR CMOS SELECT DEVICE FOR RESISTIVE SENSE MEMORY - A resistive sense memory apparatus includes a bipolar select device having a semiconductor substrate and a plurality of transistors disposed in the semiconductor substrate and forming a row or transistors. Each transistor includes an emitter contact and a collector contact. Each collector contact is electrically isolated from each other and each emitter contact is electrically isolated from each other. A gate contact extends along a channel region between the emitter contact and a collector contact. A base contact is disposed within the semiconductor substrate such that the emitter contact and a collector contact is between the gate contact and the base contact. A resistive sense memory cells is electrically coupled to each collector contact or emitter contact and a bit line. | 07-15-2010 |
20100177562 | COMPUTER MEMORY DEVICE WITH MULTIPLE INTERFACES - Various embodiments are generally directed to a method and apparatus associated with operating a first memory device with multiple interfaces and a status register. In some embodiments, a first interface is engaged by a host. A memory device that has a plurality of memory cells comprised of at least a magnetic tunneling junction and a spin polarizing magnetic material is connected to a second interface. A status register is maintained by logging at least an error or busy signal during data transfer operations through the first and second interfaces. | 07-15-2010 |
20100188883 | Simultaneously Writing Multiple Addressable Blocks of User Data to a Resistive Sense Memory Cell Array - Method and apparatus are disclosed for storing data to non-volatile resistive sense memory (RSM) memory cells of a semiconductor memory array, including but not limited to resistive random access memory (RRAM) and spin-torque transfer random access memory (STTRAM or STRAM) cells. In accordance with various embodiments, a plurality of addressable data blocks from a host device are stored in a buffer. At least a portion of each of the addressable data blocks are serially transferred to a separate register of a plurality of registers. The transferred portions of said addressable data blocks are thereafter simultaneously transferred from the registers to selected RSM cells of the array. | 07-29-2010 |
20100195380 | Non-Volatile Memory Cell with Precessional Switching - A method and apparatus for writing data to a non-volatile memory cell, such as a spin-torque transfer random access memory (STRAM) memory cell. In some embodiments, a selected resistive state is written to a magnetic tunneling structure by applying a succession of indeterminate write pulses thereto until the selected resistive state is verified. | 08-05-2010 |
20100210095 | POLARITY DEPENDENT SWITCH FOR RESISTIVE SENSE MEMORY - Methods of forming polarity dependent switches for resistive sense memory are described. Methods for forming a memory unit include implanting dopant material more heavily in a source contact than a bit contact of a semiconductor transistor, and electrically connecting a resistive sense memory cell to the bit contact. The resistive sense memory cell is configured to switch between a high resistance state and a low resistance state upon passing a current through the resistive sense memory cell. | 08-19-2010 |
20100271875 | Compensating for Variations in Memory Cell Programmed State Distributions - Method and apparatus for compensating for variations in memory cell programmed state distributions, such as but not limited to a non-volatile memory formed of NAND configured Flash memory cells. In accordance with various embodiments, a memory block is formed from a plurality of memory cells that are arranged into rows and columns within the memory block, each memory cell configured to have a programmed state. A selected row of the memory block is read by concurrently applying a stepped sequence of threshold voltages to each memory cell along the selected row while sequentially decoupling read current from groups of memory cells along the selected row as the programmed states of said groups of cells are successively determined. | 10-28-2010 |
20100302849 | NAND FLASH MEMORY WITH INTEGRATED BIT LINE CAPACITANCE - Method and apparatus for outputting data from a memory array having a plurality of non-volatile memory cells arranged into rows and columns. In accordance with various embodiments, charge is stored in a volatile memory cell connected to the memory array, and the stored charge is subsequently discharged from the volatile memory cell through a selected column. In some embodiments, the volatile memory cell is a dynamic random access memory (DRAM) cell from a row of said cells with each DRAM cell along the row coupled to a respective column in the memory array, and each column of non-volatile memory cells comprises Flash memory cells connected in a NAND configuration. | 12-02-2010 |
20110007538 | SYSTEMS AND METHODS OF CELL SELECTION IN CROSS-POINT ARRAY MEMORY DEVICES - The disclosure is related to three dimensional cross-point array memory devices and selecting cells within a three dimensional cross-point array memory. In a particular embodiment, three different voltages levels are applied to bit lines of the cross point array to allow for selection of a specific cell. Series of select devices may be implemented to provide a high voltage and a low voltage to specific bit lines, while a middle voltage may also be provided. In a particular embodiment, the select devices comprise Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs). | 01-13-2011 |
20110007545 | Non-Volatile Memory Cell Stack with Dual Resistive Elements - A non-volatile memory cell and method of use thereof. In some embodiments, an individually programmable resistive sense memory (RSM) element is connected in series with a programmable metallization cell (PMC) switching element. In operation, while the switching element is programmed to a first resistive state, no current passes through the RSM element and while a second resistive state is programmed to the RSM element, current passes through the RSM element. | 01-13-2011 |
20110007548 | Hierarchical Cross-Point Array of Non-Volatile Memory - A method and apparatus for reading data from a non-volatile memory cell. In some embodiments, a cross-point array of non-volatile memory cells is arranged into rows and columns. A selection circuit is provided that is capable of activating the first block of memory cells while deactivating the second block of memory cells. Further, a read circuit is provided that is capable of reading a logical state of a predetermined memory cell in the first block of memory cells with a reduced leak current by programming a first resistive state to the block selection elements corresponding to the first block of memory cells while programming a second resistive state to the block selection elements corresponding to the second block of memory cells. | 01-13-2011 |
20110007581 | Current Cancellation for Non-Volatile Memory - A method and apparatus for reading data from a non-volatile memory cell. In some embodiments, a cross-point array of non-volatile memory cells is arranged into rows and columns that are each controlled by a line driver. A read circuit is provided that is capable of reading a logical state of a predetermined memory cell by differentiating a non-integrated first reference value from a non-integrated second reference value. Further, each reference value is measured immediately after configuring the column corresponding to the predetermined memory cell to produce a first and second amount of current. | 01-13-2011 |
20110026305 | Non-Volatile Memory Array With Resistive Sense Element Block Erase and Uni-Directional Write - A non-volatile memory cell and associated method of use are disclosed. In accordance with various embodiments, the memory cell includes a switching device and a resistive sense element (RSE) connected in series between first and second control lines. The first control line is supplied with a variable voltage and the second control line is maintained at a fixed reference voltage. A first resistive state of the RSE is programmed by lowering the variable voltage of the first control line below the fixed reference voltage of the second control line to flow a body-drain current through the switching device. A different, second resistive state of the RSE is programmed by raising the variable voltage of the first control line above the fixed reference voltage to flow a drain-source current through the switching device. | 02-03-2011 |
20110026336 | Data Storage Using Read-Mask-Write Operation - Method and apparatus for writing data to a storage array, such as but not limited to an STRAM or RRAM memory array, using a read-mask-write operation. In accordance with various embodiments, a first bit pattern stored in a plurality of memory cells is read. A second bit pattern is stored to the plurality of memory cells by applying a mask to selectively write only those cells of said plurality corresponding to different bit values between the first and second bit patterns. | 02-03-2011 |
20110029714 | RESISTIVE SENSE MEMORY ARRAY WITH PARTIAL BLOCK UPDATE CAPABILITY - Various embodiments of the present invention are generally directed to a method and apparatus for carrying out a partial block update operation upon a resistive sense memory (RSM) array, such as formed from STRAM or RRAM cells. The RSM array is arranged into multi-cell blocks (sectors), each block having a physical block address (PBA). A first set of user data is written to a selected block at a first PBA. A partial block update operation is performed by writing a second set of user data to a second block at a second PBA, the second set of user data updating a portion of the first set of user data in the first PBA. The first and second blocks are thereafter read to retrieve the second set of user data and a remaining portion of the first set of user data. | 02-03-2011 |
20110032748 | POLARITY DEPENDENT SWITCH FOR RESISTIVE SENSE MEMORY - A memory unit includes a resistive sense memory cell configured to switch between a high resistance state and a low resistance state upon passing a current through the resistive sense memory cell and a semiconductor transistor in electrical connection with the resistive sense memory cell. The semiconductor transistor includes a gate element formed on a substrate. The semiconductor transistor includes a source contact and a bit contact. The gate element electrically connects the source contact and the bit contact. The resistive sense memory cell electrically is connected to the bit contact. The source contact is more heavily implanted with dopant material then the bit contact. | 02-10-2011 |
20110085373 | SPIN-TRANSFER TORQUE MEMORY SELF-REFERENCE READ METHOD - Self-reference reading a magnetic tunnel junction data cell methods are disclosed. An illustrative method includes applying a read voltage across a magnetic tunnel junction data cell and forming a read current. The magnetic tunnel junction data cell has a first resistance state. The read voltage is sufficient to switch the magnetic tunnel junction data cell resistance. The method includes detecting the read current and determining if the read current remains constant during the applying step. If the read current remains constant during the applying step, then the first resistance state of the magnetic tunnel junction data cell is the resistance state that the read voltage was sufficient to switch the magnetic tunnel junction data cell to. | 04-14-2011 |
20110116302 | Asymmetric Write Current Compensation Using Gate Overdrive for Resistive Sense Memory Cells - Apparatus and associated method for asymmetric write current compensation for resistive sense memory (RSM) cells, such as but not limited to spin-torque transfer random access memory (STRAM) or resistive random access memory (RRAM) cells. In accordance with some embodiments, an RSM cell includes an RSM element coupled to a switching device. The switching device has a plurality of terminals. A control circuit compensates for asymmetric write characteristics of the RSM cell by limiting a range of voltage differentials across the terminals so as to be equal to or less than a magnitude of a source voltage applied to the switching device, thereby providing bi-directional write currents of substantially equal magnitude through the RSM element. | 05-19-2011 |
20110134688 | Asymmetric Write Current Compensation - An apparatus and method for compensating for asymmetric write current in a non-volatile unit cell. The unit cell comprises a switching device and an asymmetric resistive sense element (RSE), such as an asymmetric resistive random access memory (RRAM) element or an asymmetric spin-torque transfer random access memory (STRAM) element. The RSE is physically oriented within the unit cell relative to the switching device such that a hard direction for programming the RSE is aligned with an easy direction of programming the unit cell, and an easy direction for programming the RSE is aligned with a hard direction for programming the unit cell. | 06-09-2011 |
20110149639 | Non-Volatile Memory Cell with Multiple Resistive Sense Elements Sharing a Common Switching Device - A non-volatile memory cell array and associated method of use. In accordance with various embodiments, the array includes a plurality of programmable resistive sense elements (RSEs) coupled to a shared switching device. The switching device has a common source region and multiple drain regions, each drain region connected to an associated RSE from said plurality of RSEs. | 06-23-2011 |
20110182106 | Current Cancellation for Non-Volatile Memory - A method and apparatus for reading data from a non-volatile memory cell. In some embodiments, a cross-point array of non-volatile memory cells is arranged into rows and columns that are each controlled by a line driver. A read circuit is provided that is capable of reading a logical state of a predetermined memory cell by differentiating a non-integrated first reference value from a non-integrated second reference value. Further, each reference value is measured immediately after configuring the column corresponding to the predetermined memory cell to produce a first and second amount of current. | 07-28-2011 |
20110194337 | Non-Volatile Memory Cell With Precessional Switching - A method and apparatus for writing data to a non-volatile memory cell, such as a spin-torque transfer random access memory (STRAM) memory cell. In some embodiments, a selected resistive state is written to a magnetic tunneling structure by applying a succession of indeterminate write pulses thereto until the selected resistive state is verified. | 08-11-2011 |
20110205788 | Spin-Torque Bit Cell With Unpinned Reference Layer and Unidirectional Write Current - Method and apparatus for using a uni-directional write current to store different logic states in a non-volatile memory cell, such as a modified STRAM cell. In some embodiments, the memory cell has an unpinned ferromagnetic reference layer adjacent a cladded conductor, a ferromagnetic storage layer and a tunneling barrier between the reference layer and the storage layer. Passage of a current along the cladded conductor induces a selected magnetic orientation in the reference layer, which is transferred through the tunneling barrier for storage by the storage layer. Further, the orientation of the applying step is provided by a cladding layer adjacent a conductor along which a current is passed and the current induces a magnetic field in the cladding layer of the selected magnetic orientation. | 08-25-2011 |
20110292716 | Asymmetric Write Current Compensation Using Gate Overdrive for Resistive Sense Memory Cells - Apparatus and associated method for asymmetric write current compensation for resistive sense memory (RSM) cells, such as but not limited to spin-torque transfer random access memory (STRAM) or resistive random access memory (RRAM) cells. In accordance with some embodiments, an RSM cell includes an RSM element coupled to a switching device. The switching device has a plurality of terminals. A control circuit compensates for asymmetric write characteristics of the RSM cell by limiting a range of voltage differentials across the terminals so as to be equal to or less than a magnitude of a source voltage applied to the switching device, thereby providing bi-directional write currents of substantially equal magnitude through the RSM element. | 12-01-2011 |
20110299323 | Floating Source Line Architecture for Non-Volatile Memory - A method and apparatus for writing data to a non-volatile memory cell, such as an RRAM memory cell. In some embodiments, a semiconductor array of non-volatile memory cells comprises a resistive sense element (RSE) and a switching device. A RSE of a plurality of memory cells is connected to a bit line while the switching device of a plurality of memory cells is connected to a word line and operated to select a memory cell. A source line is connected to the switching device and connects a series of memory cells together. Further, a driver circuit is connected to the bit line and writes a selected RSE of a selected source line to a selected resistive state by passing a write current along a write current path that passes through the selected RSE and through at least a portion of the remaining RSE connected to the selected source line. | 12-08-2011 |
20120008374 | Data Storage Using Read-Mask-Write Operation - Method and apparatus for writing data to a storage array, such as but not limited to an STRAM or RRAM memory array, using a read-mask-write operation. In accordance with various embodiments, a first bit pattern stored in a plurality of memory cells is read. A second bit pattern is stored to the plurality of memory cells by applying a mask to selectively write only those cells of said plurality corresponding to different bit values between the first and second bit patterns. | 01-12-2012 |
20120033482 | Bit Set Modes for a Resistive Sense Memory Cell Array - Various embodiments of the present invention are generally directed to a method and apparatus for providing different bit set modes for a resistive sense memory (RSM) array, such as a spin-torque transfer random access memory (STRAM) or resistive random access memory (RRAM) array. In accordance with some embodiments, a group of RSM cells in a non-volatile semiconductor memory array is identified for application of a bit set operation. A bit set value is selected from a plurality of bit set values each separately writable to the RSM cells to place said cells in a selected resistive state. The selected bit set value is thereafter written to at least a portion of the RSM cells in the identified group. | 02-09-2012 |
20120039111 | POLARITY DEPENDENT SWITCH FOR RESISTIVE SENSE MEMORY - A memory unit includes a resistive sense memory cell configured to switch between a high resistance state and a low resistance state upon passing a current through the resistive sense memory cell and a semiconductor transistor in electrical connection with the resistive sense memory cell. The semiconductor transistor includes a gate element formed on a substrate. The semiconductor transistor includes a source contact and a bit contact. The gate element electrically connects the source contact and the bit contact. The resistive sense memory cell electrically is connected to the bit contact. The source contact is more heavily implanted with dopant material then the bit contact. | 02-16-2012 |
20120039112 | Hierarchical Cross-Point Array of Non-Volatile Memory - A method and apparatus for reading data from a non-volatile memory cell. In some embodiments, a cross-point array of non-volatile memory cells is arranged into rows and columns. A selection circuit is provided that is capable of activating the first block of memory cells while deactivating the second block of memory cells. Further, a read circuit is provided that is capable of reading a logical state of a predetermined memory cell in the first block of memory cells with a reduced leak current by programming a first resistive state to the block selection elements corresponding to the first block of memory cells while programming a second resistive state to the block selection elements corresponding to the second block of memory cells. | 02-16-2012 |
20120087175 | Asymmetric Write Current Compensation - An apparatus and method for compensating for asymmetric write current in a non-volatile unit cell. The unit cell comprises a switching device and an asymmetric resistive sense element (RSE), such as an asymmetric resistive random access memory (RRAM) element or an asymmetric spin-torque transfer random access memory (STRAM) element. The RSE is physically oriented within the unit cell relative to the switching device such that a hard direction for programming the RSE is aligned with an easy direction of programming the unit cell, and an easy direction for programming the RSE is aligned with a hard direction for programming the unit cell. | 04-12-2012 |
20120120708 | METHOD OF SWITCHING OUT-OF-PLANE MAGNETIC TUNNEL JUNCTION CELLS - A method of switching the magnetization orientation of a ferromagnetic free layer of an out-of-plane magnetic tunnel junction cell, the method including: passing an AC switching current through the out-of-plane magnetic tunnel junction cell, wherein the AC switching current switches the magnetization orientation of the ferromagnetic free layer. | 05-17-2012 |
20120120713 | Asymmetric Write Current Compensation Using Gate Overdrive for Resistive Sense Memory Cells - Apparatus and associated method for asymmetric write current compensation for resistive sense memory (RSM) cells, such as but not limited to spin-torque transfer random access memory (STRAM) or resistive random access memory (RRAM) cells. In accordance with some embodiments, an RSM cell includes an RSM element coupled to a switching device. The switching device has a plurality of terminals. A control circuit compensates for asymmetric write characteristics of the RSM cell by limiting a range of voltage differentials across the terminals so as to be equal to or less than a magnitude of a source voltage applied to the switching device, thereby providing bi-directional write currents of substantially equal magnitude through the RSM element. | 05-17-2012 |
20120147659 | Bidirectional Non-Volatile Memory Array Architecture - Method and apparatus for transferring data in a memory. A semiconductor memory includes a plurality of memory cells each having a resistive sense element (RSE) in series with a switching device. A conductive word line extends in a first direction adjacent the memory cells and is connected to a gate structure of each of the switching devices. A plurality of conductive bit lines extend in a second direction adjacent the memory cells, each bit line providing a connection node that interconnects a respective pair of the memory cells. A control circuit senses a programmed state of a selected memory cell by setting each of the bit lines on a first side of the selected memory cell to a first voltage level, setting each of the remaining bit lines on an opposing second side of the selected memory cell to a second voltage level, and setting the word line to a third voltage level. | 06-14-2012 |
20130135922 | Floating Source Line Architecture for Non-Volatile Memory - A method and apparatus for writing data to a non-volatile memory cell, such as an STRAM memory cell or an RRAM memory cell. In some embodiments, a plurality of N non-volatile memory cells, where N is a greater than two, are connected to a common floating source line. A write circuit is adapted to program a selected memory cell of the plurality to a selected data state by passing a write current of selected magnitude through the selected memory cell and concurrently passing a portion of the write current in parallel through each of the remaining N−1 memory cells of the plurality via the common floating source line. | 05-30-2013 |
20130329490 | METHOD OF SWITCHING OUT-OF-PLANE MAGNETIC TUNNEL JUNCTION CELLS - A method of switching the magnetization orientation of a ferromagnetic free layer of an out-of-plane magnetic tunnel junction cell, the method including: passing an AC switching current through the out-of-plane magnetic tunnel junction cell, wherein the AC switching current switches the magnetization orientation of the ferromagnetic free layer. | 12-12-2013 |
20140071731 | One-Time Programmable Memory Cell - A programmable memory cell including a thick oxide spacer transistor, a programmable thin oxide anti-fuse disposed adjacent to the thick oxide spacer transistor, and first and second thick oxide access transistors. The thick oxide spacer transistor and first and second thick oxide access transistors can include an oxide layer that is thicker than an oxide layer of the programmable thin oxide anti-fuse. The programmable thin oxide anti-fuse and the thick oxide spacer transistor can be natively doped. The first and second thick oxide access transistors can be doped so as to have standard threshold voltage characteristics. | 03-13-2014 |
20150078062 | PROGRAMMABLE DIODE ARRAY FOR HIGH DENSITY OTP APPLICATION - A device for one-time-programmable (OTP) memory may include a capacitor formed by a conductive layer, an oxide layer, and a semiconductor well, and a diode that is formed after programing the device. The device may be programmable by applying a voltage between the conductive layer and the semiconductor well. The applied voltage may be capable of rupturing the oxide layer at one or more points. The conductive layer, the oxide layer, and the semiconductor well may be native CMOS process formations. | 03-19-2015 |