Abstract: A magnetic memory device which can be formed with a further reduced size. The magnetic memory device includes: a plurality of memory cells each including at least one magnetoresistive effect revealing body and arranged along a pair of lines; a plurality of auxiliary write lines arranged so that each memory cell is provided with one auxiliary write line, each auxiliary write line being connected to the pair of lines, for introducing write currents flowing through the pair of lines to the vicinity of the magnetoresistive effect revealing body; and transistors arranged so that one transistor is inserted in each auxiliary write line, for allowing the write current to flow bidirectionally through the auxiliary write line in an operating state of the transistors.

Abstract: A magnetoresistive effect element according to the present invention is comprised of a TMR element that is disposed at an intersection where a bit line and a write word line intersect with each other, in a manner sandwiched between the bit line and the write word line, and is configured such that it includes a sensitive magnetic layer whose magnetization direction is changed by a synthetic magnetic field of magnetic fields generated around the bit line and the write word line, and at the same time such that electric current flows in a direction perpendicular to the laminating surfaces thereof, and a magnetic material individually covering the bit line and the write word line at the intersection, thereby forming an annular magnetic layer associated with the bit line and an annular magnetic layer associated with the write word line. The sensitive magnetic layer comprises a magnetic material portion of the annular magnetic layers of the magnetic material, sandwiched by the bit line and the write word line.

Abstract: The present invention provides a magnetic memory device capable of performing reading operation with lower power consumption and at high read precision and a method of reading the magnetic memory device. Sense bit lines (21A, 21B) are provided in a bit line direction for each pair of magnetoresistive devices (12A, 12B) constructing a storage cell (12) and a read current is supplied. The read currents passed through the pair of magnetoresistive devices (12A, 12B) flow to the ground via a sense word line (31). Further, by providing a constant current circuit (108B) commonly for plural sense word lines (31), the sum of a pair of read currents passing through the pair of magnetoresistive devices (12A, 12B) in one storage cell constant, and information is read from the storage cell (12) on the basis of the difference between the pair of read currents. By sharing the constant current circuit (108B), variations in the sum of the pair of read currents can be reduced, and power consumption can be also reduced.

Abstract: A magnetic memory device and a sense amplifier circuit capable of obtaining a read signal output with a high S/N ratio and reducing power consumption and a circuit space, and a method of reading from a magnetic memory device are provided. In a sense amplifier, transistors (41A), (41B) which are differential amplifiers are commonly connected to one constant current circuit (50) through switches (46) ( . . . , 46n, 46n+1, . . . ). Corresponding bit decode lines (20) ( . . . , 20n, 20n+1, . . . ) and a read selection signal line (90) are connected to the switches (46) ( . . . , 46n, 46n+1, . . . ). A read/write signal is transferred from the read selection signal line (90), and the switches (46) operate according to a bit decode value and the read/write signal.

Abstract: The present invention provides a magnetic memory device based on a novel driving method realizing reliable writing and a method of writing the magnetic memory device. Four parallel portions are formed in a pair of loop-shaped write lines (6Xn) and (6Yn). Magnetoresistive devices (12A) and (12B) disposed in the parallel portion in an upper stage construct a memory cell (12Ev), and magnetoresistive devices (12A) and (12B) disposed in the parallel portion in a lower stage construct a memory cell (120d). When current in the direction from the drive point A to the drive point B is passed from the current drives (123n) and (133n), the directions of the currents in the write lines (6Xn) and (6Yn) are aligned in the parallel portion of the memory cell (12Ev) but are opposite to each other in the parallel portion in the memory cell (120d).

Abstract: A magnetic storage cell being capable of stable writing and having little adverse influence on an adjacent magnetic storage cell, and a magnetic memory device using the magnetic storage cell, and its manufacturing method are provided. In the invention, a plurality of TMR devices (1a) (1b) each including a TMR film (S20) including a connecting portion (14) of which the magnetization direction is changed by an external magnetic field and a second magnetic layer (8) and allowing a current to flow therethrough in a direction perpendicular to a laminate surface, and a toroidal magnetic layer (4) disposed on a surface of the TMR film (S20) so that a direction along the laminate surface is an axial direction and a write bit line (5) and a write word line (6) penetrate through the toroidal magnetic layer (4) are included, and the TMR devices (1a), (1b) share a part of the toroidal magnetic layer (4) between them.

Abstract: A magnetoresistive effect element includes a laminated body including a magnetosensitive layer a magnetizing direction of which is changed by an external magnetic field and constituted such that a current is made to flow in a direction orthogonal to a laminated layer face thereof, and a annular magnetic layer arranged at a side of one face of the laminated body to constitute an axial direction by a direction along the laminated layer face and constituted to be penetrated by a plurality of lead wires and therefore, a closed magnetic path can be formed by making current flow to a plurality of lead wires and inversion of magnetization at the magnetosensitive layer can further efficiently be carried out.

Abstract: A magnetic memory device includes a magneto-resistance effect element including a magnetic sensitive layer whose magnetization direction changes according to an external magnetic field; a write line to which a write current is supplied to apply an external magnetic field to the magnetic sensitive layer; and a write current drive circuit including a current direction control section for controlling the direction of the write current in the write line and a current amount control section for controlling the amount of the write current in the write line to a constant value.

Abstract: Each memory cell is constituted by a pair of magnetic memory elements. The magnetic memory elements are connected at one ends to sense bit lines, and at the other ends to a sense word line through a pair of reverse current preventing diodes, respectively. A constant current circuit is disposed on the grounded side of the sense word line. The constant current circuit has a function of fixing a current flowing through the sense word line, and is constituted by a constant voltage generating diode, a transistor and a current limiting resistor.

Abstract: Each memory cell is constituted by a pair of magnetic memory elements. The magnetic memory elements are connected at one ends to sense bit lines, and at the other ends to a sense word line through a pair of reverse current preventing diodes, respectively. A constant current circuit is disposed on the grounded side of the sense word line. The constant current circuit has a function of fixing a current flowing through the sense word line, and is constituted by a constant voltage generating diode, a transistor and a current limiting resistor.

Abstract: A magnetic memory device includes a magneto-resistance effect element including a magnetic sensitive layer whose magnetization direction changes according to an external magnetic field; a write line to which a write current is supplied to apply an external magnetic field to the magnetic sensitive layer; and a write current drive circuit including a current direction control section for controlling the direction of the write current in the write line and a current amount control section for controlling the amount of the write current in the write line to a constant value.

Abstract: A magnetoresistive effect element includes a laminated body including a magnetosensitive layer a magnetizing direction of which is changed by an external magnetic field and constituted such that a current is made to flow in a direction orthogonal to a laminated layer face thereof, and a annular magnetic layer arranged at a side of one face of the laminated body to constitute an axial direction by a direction along the laminated layer face and constituted to be penetrated by a plurality of lead wires and therefore, a closed magnetic path can be formed by making current flow to a plurality of lead wires and inversion of magnetization at the magnetosensitive layer can further efficiently be carried out.

Abstract: A flash memory system including a memory manager. The memory manager manages data transmission and reception between a host computer and a flash memory. The memory manager mutually converts a logical address in which the flash memory is accessible from the host computer, and a physical address has an actual address of the flash memory. It stores a change of internal information as &Dgr; record in said flash memory and after resetting, restores an internal state to a state before the resetting by information of the &Dgr; record. The flash memory system can be realized in which the delay of the writing/reading time can be decreased, or writing operation can be relatively easily performed, high speed operation is possible and defective sectors, defective bits and the like can be adequately managed.

Abstract: A flash memory system of the present invention comprises a memory manager for managing data transmission/reception between a host computer and a flash memory, said memory manager having an address conversion table for converting a logical address given to the flash memory from the host computer and a physical address as an actual address of the flash memory, said address conversion table being defined in accordance with minimum erasing units of the flash memory. This can realize a flash memory system which has little delay in a writing/reading time, enables a high-speed operation, and can adequately manage defective sectors, defective bits, and the like.

Abstract: A flash memories (20, 21) are coupled with a host computer (1) through a flash memory controller (2) which has a pair of data buses (27, 28), and a pair of buffer memories (22, 23). Each of said data buses is coupled with a related flash memory, and a related buffer memory, which is coupled with said host computer. Said data buses (22, 23) are controlled to operate simultaneously so that said flash memories are accessed simultaneously in parallel form. A data in said host computer is transferred to said flash memories through said buffer memories and said data buses, and vice versa. All the elements (20, 21, 2) are mounted on a plastics card (100) called a flash memory card, which is coupled with a host computer through a connector. Because of use of a plurality of buses operating in parallel form, the transfer time of data between a host computer and a flash memory card is shortened.

Abstract: A technique of an optical card having high information recording density. A specially superior writing characteristic is required for an additional recording optical card among optical cards. In the case where the optical card of additional recording type is closed, reduction in the writing characteristic is observed. In this invention, a sensitizing layer (50), which serves as escape for molten recording material at writing, is provided in rear of an optical recording section (30), so that an optical card is produced which is superior in both environmental resistance and writing ability. The sensitizing layer (50) is made of self-oxidizable or thermoplastic resin and an absorbing agent dispersed in the resin. The absorbing agent cooperates with the resin not only to improve a writing characteristic, but also to improve design ability and reading ability of the card.

Abstract: An optical recording medium includes a silver grain layer containing a large number of blackened fine silver grains and a coloring matter layer containing coloring matter on a base board and the coloring matter has an ability of absorbing near-infrared ray. When laser beam having a density of optical energy more than a boundary which represents a threshold with respect to the density of optical energy is radiated to the optical recording medium, a part of the latter is deformed to form a plurality of convexities which will be utilized as optical recording pit. The recording pits formed in this way are detected by presence or absence of reflection of radiated light whereby the content of optical recorded informations can be read. The optical recording pits are not deformed further irrespective of how long a reading light comprising laser beam having a density of energy less than the threshold is repeatedly radiated to the optical pits.

Abstract: A method of producing a plurality of masks which are used when ROM type data are written in an optical recording medium for ROM type optical recording cards. The method is practiced by way of steps of producing a mother mask having a preformatting pattern, next, transcribing the preformatting pattern for the mother mask, next, producing a master mask having a required optical recording pattern written therein and next, producing a working mask from the master mask. When the preformatting pattern is prepared in a writable type, writing or inspecting of the master mask or inspecting of the working mask or mother mask can be achieved using a writing/reading apparatus for writable type optical recording cards.

Abstract: In an optical card, a card substrate has its rigidity which is sufficient to handle the card substrate independently. The card substrate has a first side which serves as a reading side upon which reading light is incident. An optical-data recording section includes a light-reflective pattern. The optical-data recording section is arranged on one of the first and second sides of the card substrate. Optical data incident upon the optical-data recording section toward the reading side of the card substrate is recorded by the optical-data recording section. A shielding layer is arranged on one of the first and second sides of the card substrate, for shielding the optical-data recording section from a viewer's field of view. The shielding layer has its transmission characteristic with respect to the reading light, which is sufficient to shield light within a visual range and to enable reading of the optical-data recording section.

Abstract: A certification card such as ID card or the like includes a hologram and an optical recording portion. Hologram is such that an amplitude and a phase of a light wave emitted from an object are recorded and an image of the object is rebuilt by emitting light to reproduce of an amplitude and a phase of the thus emmited light. An optical recording technique for use with the card employs data pits which are formed on an optical reflective surface of an optical recording layer. The thus formed data pits are detected by difference in optical reflectivity from the data pits when the object is illuminated by laser beam so that data are read. The card is constituted by adhering a card front substrate to a card rear substrate, and hologram and optical recording portion are formed between the card front substrate and the card rear substrate. The certification card is difficult to falsify and alter and, therefore, has high safety.