Abstract:
A read circuit for sensing a resistance state of a resistive switching device in a crosspoint array utilizes an equipotential preamplifier connected to a selected column line of the resistive switching device in the array. The equipotential preamplifier delivers a sense current while maintaining the selected column line at a reference voltage near a biasing voltage applied to unselected row lines of the array. The read circuit has a reference current source for generating a sense reference current, and a current comparator connected to evaluate the sense current delivered by the equipotential preamplifier against the sense reference current and generating an output signal indicative of the resistance state of the resistive switching device.
Abstract:
A memory array has a plurality of conductor structures. Each conductor structure has a top wire segment extending in a first direction, a middle wire segment extending in a second direction at an angle from the first direction, a bottom wire segment extending in a direction opposite to the first direction, and a via connecting the top, middle, and bottom wire segments. A plurality of memory cells in an upper plane of the memory array are formed at intersections of the middle wire segment of each conductor structure with the top wire segments of neighboring conductor structures, and a plurality of memory cells in a lower plane are formed at intersections of the middle wire segment of each conductor structure with the bottom wire segments of neighboring conductor structures.
Abstract:
A memory array with write feedback includes a number of row lines intersecting a number of column lines, a memory element connected between one of the row lines and one of the column lines, an electrical condition supply to be selectively applied to one of the row lines; and a feedback control loop to control an electrical condition supplied by the electrical condition supply. A method for setting the state of a memory element within a memory array includes applying an electrical condition to the memory element within the memory array, sensing a resistive state of the memory element, and controlling the electrical condition based on the sensed resistive state to cause the memory element to reach a target resistance.
Abstract:
A digital current source used to mirror a reference current is provided. The digitally controlled analog current source multiplies a current from a master mirror transistor producing an output current that is a digitally controlled multiple of the reference current. The circuit comprises a plurality of one bit current mirror cells. Each one bit current mirror cell comprises a mirror transistor receiving an analog gate voltage from a master mirror transistor and providing a drain voltage, an operational amplifier configured to maintain the drain voltage for the mirror transistor equivalent to the analog gate voltage, and a switch configured to receive one control bit, the switch enabling current mirroring when the mirror voltage is substantially equivalent to the master mirror voltage. The digital current source further includes a common line summing element employed to receive and compile currents from each of the one bit current mirror cells.
Abstract:
A flexible media magnetic printing system provides for data storage within flexible media imprinted with magnetic ink. In a particular embodiment, the printing system includes at least one reservoir of magnetic ink with magnetic particles capable of supporting high density data, and at least one reservoir of visible ink. The reservoirs are coupled to a print head including one or more ink-ejecting nozzles, which is removably or fixedly coupled to at least one magnetic read/write device. The magnetic read/write device tracks above the magnetic ink applied by the ink-ejecting nozzles to the flexible media. The magnetic read/write device writes to the magnetic ink by providing a magnetic field of sufficient intensity to re-orient the magnetic alignment within the ink to a known direction. The magnetic read/write device also reads data from flexible media, for example, paper or cloth that is imprinted with data-embedded magnetic ink. Visible or substantially invisible magnetic ink may be applied as dots within or strips beneath characters printed in visible ink. An inkjet printer head incorporating the flexible media magnetic printing system is further provided.
Abstract:
A cross point resistive memory array has a first array of cells arranged generally in a plane. Each of the memory cells includes a memory storage element and is coupled to a diode. The diode junction extends transversely to the plane of the array of memory cells.
Abstract:
The invention includes an apparatus and method for selecting a desirable magnitude of a magnetic memory cell write current. The method includes determining a minimal magnitude of write current for writing to the magnetic memory cell, determining a maximal magnitude of write current for writing to the magnetic memory cell, and calculating the selected magnitude of magnetic memory cell write current based on the minimal magnitude of write current and the maximal magnitude of write current.
Abstract:
A thin film device and a method of providing thermal assistance therein is disclosed. Accordingly, a heater material is utilized to thermally assist in the operation of the thin film device. By utilizing a heater material to thermally assist in the operation of the thin film device, a substantial improvement in the accuracy and performance of the thin film device is achieved. A first aspect of the present invention is a thin film device. The thin film device includes at least one patterned thin film layer, a heater material coupled to the at least one patterned thin film layer for providing thermal assistance to the at least one of the patterned thin film layers and a conductor coupled to the heater material for supplying energy to the heater material.
Abstract:
A system and method for determining the logic state of a memory cell in a magnetic tunnel junction (MTJ) memory device based on the ratio of the current through the cell at different bias points are disclosed. A memory cell in an MJT memory device is sequentially subjected to at least two different bias voltages. The current through the cell at each of the bias voltages is measured, and a ratio of the different currents is determined. The ratio is then compared with a predetermined value to determine the logic state of the cell. The predetermined value can be a known value. Alternatively, the predetermined value can be determined by application of the system and method to a reference cell having a known logic state.
Abstract:
A memory cell sensor including an integrator for sensing a logical state of a memory cell. An integrator calibration circuit provides a corrective bias to the integrator, the corrective bias being based upon a difference between an initial integrator output value and a reference value. Another embodiment includes a method of sensing a logical state of a memory cell. The memory cell being sensed by an integrator. The method includes determining an initial integrator output value when a corrective bias of the integrator is zeroed, generating a correction value by comparing the initial integrator output value to a reference value, and applying the correction value to the corrective bias of the integrator.