JPS6244356B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic bubble transfer switching circuit. More specifically, the present invention relates to a switching circuit for a magnetic bubble transfer path in a current access magnetic bubble element.

As a method for improving the efficiency of access time of a storage element using a magnetic bubble (hereinafter referred to as a bubble element), it is well known to configure the bubble element into a major/minor loop configuration.

This major/minor loop configuration includes a large number of loop-shaped magnetic bubble transfer paths (minor loops) for storing information, and a magnetic bubble transfer path (major loop or major line, hereinafter collectively referred to as major loop) for reading or writing information. ), the memory configuration has a short average access time for information and a high tolerance to defects caused by the bubble element manufacturing process.

One of the essential functional elements in a magnetic bubble element with a major/minor loop configuration is to transfer information from the minor loop to the major loop with good controllability (transfer out), and to transfer information on the major loop to the minor loop with good controllability. (transfer in) function. The element that performs this function is usually called a magnetic bubble transfer switching circuit (transfer gate, hereinafter referred to as TR gate).

In order to further reduce the information access time of the magnetic bubble element, it is effective to use a major/minor memory configuration and to increase the magnetic bubble transfer speed. It is well known that the transfer speed of magnetic bubbles is faster when the magnetic bubble is driven by current drive than by in-plane rotating magnetic field drive. As such a current-driven magnetic valve element, a current-access type element in which a two-layer conductor having an oblong slot array is used as a magnetic bubble driving pattern was developed by AH Bobeck in August 1979. Lunar Literature The Bell System Technical Journal
Technical Journal) Vol. 58 No. 6 No. 1453-No.
It has been well known since it was introduced on page 1540. Since the current access type magnetic bubble element using Bobeck has a large minimum pattern size, it is easier to apply to microbubbles than the conventional in-plane rotating magnetic field driven type magnetic bubble element using a permalloy pattern.

Even in this current access type magnetic bubble element, the usefulness of having the memory configuration as a major/minor loop configuration is the same as in the case of the in-plane rotating magnetic field drive type.

Therefore, it is important to efficiently configure the TR/gate for transferring magnetic bubble information between the major loop and the minor loop.

The above document also describes TR gates. There, the operation of the TR/gate is performed by complexly modulating the order in which the driving current pulses of the magnetic bubbles are generated. Also, the conductor slot pattern of the TR/gate portion requires a very special shape. Such a TR gate therefore has the disadvantage of requiring a drive circuit for complexly controlling the drive current pulse train of the magnetic bubble. or,
By applying a complex drive current pulse train,
The start-stop problem can be cited as deteriorating the operational stability of the magnetic bubble in the simple loop section, which is unrelated to the TR/gate operation. Moreover, since the shape and arrangement of the conductor slots as a magnetic bubble transfer pattern is limited to a very specific shape, there is a flaw that reduces the operating margin for simple transfer.

An object of the present invention is to eliminate the drawbacks of the magnetic bubble transfer switching circuit in the conventional current access type magnetic bubble element and to provide a large degree of freedom as a transfer pattern.
The goal is to provide TR/Gate.

The principle of the invention is as follows. When the magnetic bubble comes to the transfer path switching section from the first transfer path to the second transfer path, the transfer path switching section is changed by passing current through a conductor pattern different from the magnetic bubble driving conductor layer. A local bias magnetic field gradient is applied, and the magnetic bubble can be moved from the first transfer path to the second transfer path by the bias magnetic field gradient and the magnetic field gradient generated from the original transfer pattern. At this time, the order of generation of current pulses that lead to the magnetic bubble drive conductor layer may be the same as the order of current pulses in a normal transfer path.

Next, the present invention will be explained in detail using the drawings. FIG. 1 shows the general configuration of the present invention. That is, as shown in FIG. 1A, a magnetic thin film 1 that is grown on a nonmagnetic substrate 2 and that can hold magnetic bubbles 11
, magnetic bubble driving conductor layers 31 and 32 having rectangular or elliptical slots 20 separated from each other by a suitable spacer thereon, and transfer direction control conductor layers 31 and 32 for applying a local magnetic field gradient to control the magnetic bubble transfer direction. It is composed of a conductor pattern layer 33. Bubble driving currents 41 and 42 and transfer control current 43 are connected to the conductor layers 31, 32 and 33, respectively.

FIG. 1B shows the conductive pattern 33 for controlling the transfer direction.
Distribution 1 of bias magnetic field components generated when a control current 43 is passed through a belt-shaped conductor as
It is a figure showing 0. In the case of such a strip-shaped conductor pattern, a bias magnetic field gradient perpendicular to the current direction (conductor length direction) is generated. This bias magnetic field gradient forces the magnetic bubble in the center of the conductor pattern 33 to move toward one edge of the conductor. In the other edge directions, the bubble is subjected to a force that prevents its movement.

Therefore, in a magnetic bubble element having a major/minor loop configuration or a similar configuration, the transfer direction control conductor is placed in the TR/gate portion where the first magnetic bubble transfer path and the second magnetic bubble transfer path are close to each other. By providing the pattern 33, the magnetic bubble can be easily moved from the first transfer path to the second transfer path.

Next, the present invention will be explained in more detail using FIG. 2 showing a first embodiment.

The figure is a plan view showing the TR/gate section according to the present invention. The shaded pattern here is the conductor layer 3.
In slot 2, the white pattern is the conductor layer 31.
slot. Magnetic bubble driving current 41J ₁
When 42J ₂ is repeatedly applied in the order of directions a, b, c, and d as shown in the drawing, the magnetic bubbles in Path 1 are sequentially transferred from a → b → c → d of the transfer pattern 20 to TR.
Transferred from a ₁ to b ₁ of gate transfer pattern 21,
The data is transferred again to c ₁ →d ₁ of the transfer pattern 20 of Path 1.

On the other hand, when transferring from Path1 to Path2, a current 43J 3 is applied to the transfer direction control conductor pattern 33 at the timing of the current application direction (b→c) corresponding to the transfer of the magnetic bubble from the pattern 21 to the pattern ₂₀ of Path1. It gets through. pattern 21
The magnetic bubble at b ₁ moves to the stable point c ₂ of the pattern 21 rather than to the stable point c ₁ of the pattern 20 due to the bias magnetic field gradient of the conductor pattern 33, so the current J ₃ is cut off at this time. For the subsequent driving current direction d→a→b→c, the magnetic bubble moves from d ₂ of pattern 21 to a ₃ → b ₃ of pattern 20 of Path 2.
Transferred as →c ₃ . In other words, the magnetic bubble of Path 1 is caused by the conductor pattern for controlling the transfer direction and its current.
This means that it has been transferred to Path 2.

The bubble in Path 2 can be similarly transferred to Path 1 by reversing the direction of the transfer direction control current. Also, throughout this transfer period, the order of application of the magnetic bubble driving current is always a repeat of a→b→c→d→a. As can be seen from this first embodiment, the TR/gate transfer pattern 21 has a magnetic bubble stable point near the first transfer path Path1 and a magnetic bubble stable point near the second transfer path within one cycle of applying current for magnetic bubble driving. It is necessary that the shape generates a stable point close to Path2. Furthermore, it is important that this transfer pattern 21 be located near the conductor pattern for controlling the direction of magnetic bubble transfer.

Next, a second embodiment of the present invention will be described with reference to FIG.

In this embodiment, the TR/gate transfer pattern 21
The shape of the magnetic bubble and the direction of magnetic bubble transfer in the second transfer path Path2 are different from those in the first embodiment. In this embodiment, the _first
Next, the magnetic bubble at position b ₁ of transfer path Path 1 is transferred to c ₂ instead of moving to c ₁ . After that, the path 2 is transferred as c ₂ → d ₂ → a ₃ → b ₃ .

A third embodiment of the present invention will be described using FIG. 4. In this embodiment, the transfer direction control conductor pattern 33 is arranged in a meandering manner near the TR/gate pattern 21. Magnetic bubble driving current J ₁ ,
As the application order of J ₂ is repeated as a→b→c→d→a, the magnetic bubble is transferred as in the position a→b→c→d→a ₁ of the transfer pattern 20 of the first transfer path Path1. Next, when applying a driving current in the direction b, a control current of 43J ₃ is applied to the control conductor pattern 33.
pass through. A portion 36 where the first bubble holding bias magnetic field locally increases due to the meandering of the control conductor pattern 33, a portion 35, 35' where the bias magnetic field locally decreases, and the bias magnetic field gradient generated therebetween. Therefore, the magnetic bubble does not move to the TR/gate pattern _21b1 , but goes toward b'.
Further, as the drive current direction changes from c to d, the magnetic bubble passes through c' of pattern 21 and reaches _d2 . When the magnetic bubble reaches d ₂ , the control current J ₃
cut. After that, the magnetic bubbles are sequentially transferred through the second transfer path Path2 according to the drive current direction a → b → c → d.
It is transferred as follows: ₃ →b ₃ →c ₃ →d ₃ .

In the case of this embodiment, when transferring the magnetic bubble from the second transfer path Path2 to the first transfer path Path1, the direction of the control current _J3 does not need to be reversed. Compared to the previous case, the timing of passing the control current _J3 is
This is possible by shifting it by 180°.

As described above, by using the present invention, there is no need to complicatedly control the sequence of magnetic bubble driving currents, and therefore a TR/gate that can operate stably can be realized. Furthermore, the arbitrariness of the TR/gate transfer pattern is greater than that of the conventional example, making it easier to realize a TR/gate pattern with simple magnetic bubble transfer characteristics. Also, in the conventional example, a third layer conductor pattern different from the transfer pattern is used for the magnetic bubble detector when realizing all the functions as a magnetic bubble element. From this, it goes without saying that the use of the third control conductor layer of the present invention is not disadvantageous in terms of manufacturing process compared to the conventional example.

In addition, in the above explanation, the case where the magnetic bubble transfer direction control conductor layer is located on the top of the magnetic bubble driving conductor layer, but its position may be between two layers of the driving conductor layer, or Of course, the effects of the present invention are exactly the same even between the magnetic bubble material and the first driving conductor layer.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the general operation of the present invention.
The figure is a perspective view showing a part of the configuration, and the figure B is a diagram explaining the principle of operation. FIG. 2 is a plan view showing a first embodiment of the present invention, FIG. 3 is a plan view of a second embodiment, and FIG. 4 is a plan view of a third embodiment. 1 is a magnetic material that holds magnetic bubbles, 2 is a growth substrate, 11 is a magnetic bubble, 20 is a conductor slot,
31, 32 are conductor layers for driving magnetic bubbles; 33 are conductor patterns for controlling the direction of magnetic bubble transfer; 41, 4;
2 and 43 are the currents flowing through the conductor layers 31, 32, and 33, respectively; 10 is the distribution of the bias component of the magnetic field generated by the conductor 33; 21 is the TR/gate slot pattern; a, b, c, d, a ₁ , b ₁ , c ₁ , d ₁ ,
a ₂ , b ₂ , c ₂ , d ₂ , a ₃ , b ₃ , c ₃ , d ₃ are the direction of the driving current and the stable position of the magnetic bubble in each direction,
Path1 and Path2 represent a first transfer path and a second transfer path, respectively.

Claims (1)

[Claims] 1. A driving conductor layer having a slot row as a magnetic bubble drive pattern, first and second magnetic bubble transfer paths constituted by the slot row,
In a current access magnetic bubble element having a magnetic bubble transfer switching transfer pattern common to these transfer paths, a transfer direction control conductor pattern different from the magnetic bubble driving conductor layer is provided in the vicinity of the transfer switching transfer pattern. A magnetic bubble transfer switching circuit comprising a layer. 2. The transfer switching transfer pattern has a structure in which a portion common to the first transfer path and a portion common to the second transfer path can become stable magnetic bubble positions within one cycle of the magnetic bubble driving current. A magnetic bubble transfer switching circuit according to claim 1. 3. The magnetic bubble transfer switching circuit according to claim 1, wherein the transfer direction control conductor pattern layer has a simple band shape. 4. The magnetic bubble transfer switching circuit according to claim 1, wherein the transfer direction control conductor pattern layer has a meandering shape.