JPS5911983B2 - Bubble domain generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to magnetic bubble storage devices, and more particularly to bubble domain generators thereof.

In recent years, magnetic bubble storage devices have come into practical use as large-capacity nonvolatile memories that replace magnetic disk devices and the like. This magnetic bubble storage device has the following advantages compared to the magnetic disk device described above.

■) Maintenance is easy because there are no moving parts and therefore no wear.

11) There is no generation of noise, etc.

111) Low power consumption as there is no drive device such as a motor that consumes large amounts of power.

IV) It can be made small and lightweight and is portable.

10V) The number of parts is small and assembly is easy.

Although the magnetic bubble storage device has various advantages as described above, its basic structure will be explained below. FIG. 1 shows a typical configuration example of a magnetic 15 bubble chip used in a magnetic bubble utilization device.

The illustrated configuration is a so-called major/minor loop configuration, and in the figure, 1 is a major loop, 2 is a minor loop, 3 is a detector, 4 is a generator, 5 is a replicator, 6 is an annihilator, T indicates the transfer gate. In the figure, the solid line represents a magnetic bubble transfer path formed by a permalloy pattern formed on a magnetic thin plate, and the broken line represents a conductive pattern made of gold or the like also formed on the thin plate. The operation is performed as follows. Two! 5. First, in accordance with the information to be written, a current is supplied within the loop of the conductive pattern constituting the generator 4 in a direction that effectively weakens the bias magnetic field to generate a magnetic bubble within the loop.

The generated magnetic bubble is transferred over the major loop 1 by the driving magnetic field rotating in the in-plane direction of the magnetic thin plate, and one piece of information (
For example, one word). At this time, current is supplied to the conductor pattern constituting the transfer gate 7 to send the magnetic bubble group on the major loop 1 into each minor loop 55-2. The magnetic bubbles sent into each minor loop 2 begin to circulate within the minor loop 2 due to the driving magnetic field, and storage of information is completed. Step 5 - Next, to read information, when the magnetic bubble group in each minor loop 2 to be read reaches a position facing the transfer gate 7, the conductor pattern is energized and transferred onto the major loop 1. .

The magnetic bubble array transferred onto the major loop is sequentially transferred by the driving magnetic field and reaches the replicator 5. The replicator 5 divides the incoming magnetic bubble into two, sends one bubble along the permalloy pattern to the detector 3, and the other via the major loop 1 to the minor loop again. The detector 3 magnifies the magnetic bubbles that arrive one after another in order to increase the detection efficiency, and reads out, for example, a change in the electrical resistance of the magnetoresistive element due to the arrival of the bubbles as a change in voltage. In addition, after reading, when erasing the information and writing new different information, the magnetic bubble after division is erased by the annihilator 6 on the measurer loop, and new different information is written by the generator 4. It's crowded. FIG. 2 is a diagram showing the structure of a bag containing the magnetic bubble chip shown in FIG. 1.

In the figure, 8 is a magnetic bubble chip, 9 is a chip mounting plane, 10 is an XY coil for generating a driving magnetic field, 11 is a ferrite yoke, 12 is a thin plate magnet for applying a bias magnetic field, and 13 is a shield case. XY for driving magnetic field generation
Triangular wave currents having a phase shift of 90° as shown in FIG. 3A are applied to each coil to obtain a force-shaped rotating magnetic field locus as shown in FIG. 3B. Driving with triangular wave current has various advantages over driving with sine wave current, such as a simple drive circuit, a small number of parts, low drive voltage, and easy integration. ing. The present invention relates to the above-mentioned magnetic bubble utilization device, particularly to a generator. By the way, since the above-mentioned generator generates a local magnetic field, its conductor pattern is minute and the density of the current flowing therein is also extremely high.

In particular, in high-density magnetic bubble storage devices, the current density is so high that the conductor deteriorates.

That is, when DC current is applied continuously, the conductor may even break in ten seconds, and even with pulsed current (pulse width 200 ns), deterioration progresses gradually. Furthermore, a disk type generator is conventionally known as a generator that generates bubble magnetic domains without applying current at such a high current density. In this disk type generator, one permalloy disk holds one bubble magnetic domain as a seed, and new bubble magnetic domains are generated by dividing the bubble magnetic domain as necessary. In this case, the bubble magnetic domain serving as the seed moves around the outer periphery of the disk in accordance with the rotating magnetic field, and its moving speed is therefore proportional to the seed of the disk diameter and the frequency of the rotating magnetic field.

On the other hand, the maximum moving speed of the bubble magnetic domain is limited by the chip material and the like.

Therefore, in order to increase the frequency of the rotating magnetic field and increase the information processing speed of the storage device, the diameter of the disk must be reduced. However, if the diameter of the disk is made too small, it will not be possible to stably hold the bubble magnetic domain that becomes the seed.

Therefore, there is a drawback that the information processing speed cannot be increased very much after all. In view of the above, an object of the present invention is to provide a generator that can increase response speed and does not require high current density energization. In a bubble magnetic domain generator that selectively supplies information according to information, a closed path that rotates a plurality of bubble magnetic domains that are close to or intersect with the end of the conveyance path in cooperation with a rotating magnetic field, and a closed path that is localized to the adjacent or intersecting portion A single conductor path that applies a magnetic field only when energization is applied, generates a plurality of bubble magnetic domains on the closed path at the time of initial energization, fills the closed path with a plurality of bubble magnetic domains, and thereafter operates the single conductor path according to the written information. This is achieved by energizing one conductor path in the opposite direction to the initial energization, dividing the bubble magnetic domain on the closed path and supplying it to the conveyance path. This will be explained in detail. 4 and 5 are diagrams illustrating an initial energized state and a normal operating state, respectively, of a generator according to the present invention. In the figure, 21 is a series of permalloy patterns arranged to form a transport path for transporting bubble magnetic domains to a minor loop (or major loop, not shown), and 22 is a series of permalloy patterns each capable of holding one bubble magnetic domain. 12 permalloy patterns are arranged to form a closed path, and 23 is an auxiliary permalloy pattern that is placed at the bent part of the closed path and assists the movement of the bubble magnetic domain, B,, B2...B2l, B22 is a bubble magnetic domain, and 100 is a conductor through which a high density current G for bubble generation and a low intensity current 1R for bubble splitting flow.

As shown in FIG. 4, in the present invention, when the conductor 100 is initially energized, a current that produces a local magnetic field in the opposite direction to the bias magnetic field;
That is, a high density current IG for bubble generation is passed through the conductor 100, thereby generating a bubble magnetic domain B1.

The bubble magnetic domain B1 generated in this way moves on the Nomalloy pattern 22 as shown by the broken line 1 due to the rotating magnetic field, and when the phase of the rotating magnetic field advances by 360 degrees, the bubble magnetic domain B2
Reach the position indicated by . At this time, the high density current G for generating bubbles is passed through the conductor 100 again to generate the next bubble magnetic domain.

Repeat the above 12 times, that is, Panimaroy pattern 22
(on the closed path), bubble magnetic domains will be present in all 12 Permalloy patterns 22, and the initial energization ends.

This initial energization is performed to generate a bubble magnetic domain that becomes a seed, and once generated, it is impossible for the seed to disappear under normal usage conditions. Therefore, if the initial energization is performed only a few times at first, it is not necessary thereafter. Therefore, the high-density current G flows through the conductor 100 for an extremely short period of time, and deterioration of the conductor 100 can be ignored.

Next, after the initial energization, as shown in FIG. 5, the seed bubble magnetic domain on the closed path is divided into two bubble magnetic domains Bll and Bl2 based on the written information, and the single force Bll is returned to the original closed path. , and the other one Bl2 is supplied to the conveyance path.

The seed bubble magnetic domain is divided at this time by passing a bubble splitting low-density current 1R through the conductor 100 when the seed bubble magnetic domain is about to pass through the conductor 100. The local magnetic field generated by this energization has the same direction as the bias magnetic field at the center of the seed bubble magnetic domain to be divided, and the opposite direction at the outside (both sides), and as a result, the seed bubble magnetic domain is pulled to both sides. It is stretched and cut in the center at the same time. The bubble magnetic domains Bll and Bl2 thus divided are attracted to the permalloy pattern magnetized by the rotating magnetic field, and on the one hand B22 moves to the conveying path side, and on the other hand Bl2 moves to the adjacent permalloy pattern on the closed path.

Here, looking at the moving speed of the bubble magnetic domains Bll, B2l, etc., the permalloy pattern 22 forming the closed path can transport the bubble magnetic domains from one neighbor to the next, and there is no need to keep them in one place. The diameter can be made relatively small.

Therefore, there is no disadvantage of having to lower the frequency of the rotating magnetic field to match the generator, which is the case with conventional disk-type generators.

That is, the frequency of the rotating magnetic field can be increased to the highest frequency allowed by the conveyance path or the like. As can be seen from the above explanation, according to the present invention, by only passing a high-density current for a very short period of time when a seed bubble magnetic domain is generated, the required bubble magnetic domain can be generated thereafter by a low-density current. Since the life of the conductor is long and the seed bubble magnetic domain is made up of a plurality of particles and circulates on a closed path composed of a normal-sized permalloy pattern, it is possible to provide a magnetic bubble memory with a high response speed.

[Brief explanation of drawings]

Fig. 1 is a diagram showing an example of the circuit configuration on a chip of a magnetic bubble storage device, Fig. 2 is a partially cutaway perspective view showing the overall configuration, and Fig. 3 is a diagram showing an example of the driving force method of a rotating magnetic field. , 4th
5 and 5 are diagrams showing an initial energized state and a normal state, respectively, of the bubble domain generator according to the present invention. 1... Major loop, 2... Minor roof, 3... Detector, 4... Generator, 5... Duplicator, 6 ...Eraser, 7
...Transfer gate, 8...Chip, 9...Chip mounting plane, 10...
... XY coil for driving magnetic field generation, 11 ... Ferrite. Yoke, 12... Thin plate magnet for bias magnetic field application D, 13... Shield case, 21... Vermalloy pattern of conveyance path,
22...Closed path permalloy pattern, 23
...Auxiliary Vermalloy pattern, 100...
...Conductor, B,,B2~Bl,,B22...
Bubble magnetic domain, IG... Current for bubble generation, R.
...Bubble splitting current.

Claims (1)

[Claims] 1. In a bubble magnetic domain generator that selectively supplies bubble magnetic domains to a predetermined transport path according to written information, a closure that circulates a plurality of bubble magnetic domains that are close to or intersect with the end of the transport path in cooperation with a rotating magnetic field. and a single conductor path that applies a local magnetic field only when energizing is applied to the adjacent or intersecting portion, and generates a plurality of bubble magnetic domains on the closed path at the time of initial energization, and forms the closed path with a plurality of bubble magnetic domains. A magnetic domain generator characterized in that the magnetic domain generator is filled with electricity and thereafter energizes the single conductor path in a direction opposite to the initial energization direction according to the written information to divide the bubble magnetic domain on the closed path and supply it to the transport path.