JPS6360477B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic bubble memory chip, and particularly to a minor loop structure for storing information in magnetic bubbles.

FIG. 1 is an enlarged plan view of essential parts showing the circuit configuration of a magnetic bubble memory chip. In the figure, 1 is a minor loop that stores information, 2 is a read track that transfers read information, and 3 is a write track that transfers write information.Read track 2 and write track 3 transfer magnetic bubble information to minor loop 1. It constitutes an input/output track for input/output. 4 is a detector that reads magnetic bubbles;
5 is a generator for writing magnetic bubbles; 6 is a replicate gate for copying the information on the minor loop 1 to the read track 2; and 7 is a swap gate for replacing the information on the write track 3 with the information in the minor loop 1.

Figures 2a to 2d are enlarged plan views of main parts showing conventional and recently proposed minor loop structures, and the minor loop 1 shown in Figure 2a is the one that has been used for the longest time and is a simple closed loop structure. The example shown in FIG. 1 also has this structure, and this is usually called an I-shaped minor loop. On the other hand, the shapes b, c, and d in the same figure have recently come into widespread use, and have a folded structure.
This means that the gates 6 and 7 explained in FIG.
It has the feature that it can be designed approximately twice as large as the case of , and the characteristics of the gates 6 and 7 can be stabilized. Therefore, these figures b to d have a high degree of integration,
The shape shown in figure b is called a G-shape, the shape shown in figure C is called an S-shape, and the shape shown in figure d is called a C-shape. The present invention relates to a case where the minor loop has a folded structure.

However, since the minor loop 1 of the folded structure with the above configuration has a complicated pattern structure,
The following problems arose. In other words, the diameter of the magnetic bubble used has been miniaturized from approximately 2 μm to approximately 1.5 μm, and the period of the basic elements that make up the minor loop has become approximately
When increasing the density from about 8 μm to about 6 μm, there was a problem that the magnetic bubble transfer characteristics became unstable and the bias magnetic field margin was halved.

Therefore, it is an object of the present invention to solve the above-mentioned conventional problems and provide a magnetic bubble memory chip with a folded structure minor loop that operates stably with a wide bias magnetic field margin even when the density is increased. .

In order to achieve such an object, the present invention widens the space at the corner of the minor loop by forming a portion of the linear transfer path of the minor loop from a parallel state to a non-parallel state.

The magnetic bubble memory chip according to the present invention will be explained in detail below.

First, before explaining the present invention, the structure of a folded minor loop will be explained in order to facilitate understanding of the present invention. As explained in FIGS. 2b to 2d, the folded minor loop 1 has a more complicated configuration than the folded minor loop 1 explained in FIG. and
The 180° corner road section 1b can be separated into two types of elements, and is formed by combining these two types of elements 1a and 1b.
The dotted line inside is the decomposition line into these two types of elements 1a and 1b. These are explained more clearly in Fig. 3. Fig. 3 a and b take as an example the minor loop 1 of the form shown in Fig. 2 b and c, and decompose it into two types of elements 1a and 1b. The figure shows a specific example in which the thin line indicates the straight transfer path section 1a, and the thick line indicates the 180° corner section 1b.
It is.

Therefore, the conventional minor loop 1 is as shown in Fig. 2,
As shown in FIG. 3, the linear transfer path portions 1a adjacent to each other were formed in a parallel state at any position.

On the other hand, as mentioned above, when the density of the magnetic bubble memory chip increases, the magnetic bubble memory characteristics become unstable and the bias magnetic field margin ΔH _B is halved due to the 180° corner path 1b. The inventors' experiments have revealed that the linear transfer path section 1a operates without problems. However, as shown in Fig. 3, there are multiple types of 180° corner road sections 1b within one minor loop 1, with 4 in the case of Fig. 3a and 6 in the case of Fig. 3b.
It is not all of these 180° corner paths 1b, but only a small number of 180° corner paths 1b that reduce the bias magnetic field margin ΔH _B by half. . and,
The 180° corner path section 1b, which has unstable operating characteristics that reduces the bias magnetic field margin ΔH _B by half, can be operated completely stably without any bias magnetic field margin ΔH _B loss by simply increasing its space. I found out experimentally that it can be done.

Therefore, the minor loop of the magnetic bubble memory chip according to the present invention changes the straight line transfer paths, which were conventionally parallel to each other at any position, from partially parallel to non-parallel, thereby eliminating the problematic 180° corner path. It has a wider space.

Embodiments of the present invention will be described in detail below with reference to the drawings.

4 and 5 are enlarged plan views showing embodiments of the minor loop of the magnetic bubble memory chip according to the present invention. FIG. 4 is an example in which the shape of the minor loop 1 is G-shaped, and FIG. 5 is the shape of the minor loop. The figures show examples in which the figures are S-shaped, and the same symbols as in the previous figure are the same elements, so their explanation will be omitted. In these figures, the spaces of all the 180° corner sections 1b constituting the minor loop 1 are formed wide. In this case, the thin lines indicate the straight transfer path portion 1a and the thick lines indicate the 180° corner line 1b, as in FIG. 3 described above. A nonparallel linear transfer path portion 1c is formed between the 180° corner path portion 1b and the linear transfer path portion 1a.
The 180° corner road portion 1b has a wide space.

FIG. 6 is an enlarged plan view of a main part showing an example of a specific transfer pattern of the above-mentioned non-parallel linear transfer path section 1c. In these figures, the non-parallel linear transfer path section 1c has asymmetric chevron patterns 8 and 9 with different foot heights on the left and right sides as shown in a and b of the figure, and is arranged in an oblique direction as shown in c and d of the figure. It can be easily formed by arranging.

In the above embodiment, a case has been described in which all the spaces of the 180° corner road included in the minor loop are widened, but the present invention is not limited to this, and only the space of a specific corner road is widened. Of course, the same effect as described above can be obtained even when the distance is made wider.

Furthermore, it goes without saying that the same effect as described above can be obtained even if the means for widening the space by making the shapes non-parallel is applied to shapes other than those explained in FIGS. 4 to 6.

As explained above, according to the present invention, there is no characteristic deterioration due to a 180° corner path, and a folded minor loop that can operate stably with a wide bias magnetic field margin can be obtained, which is an extremely advantageous feature for increasing the density of magnetic bubble memory elements. It has a good effect.

[Brief explanation of the drawing]

Fig. 1 is an enlarged plan view of the main part showing an example of a magnetic bubble memory chip, Fig. 2 is an enlarged plan view of the main part showing the configuration of the minor loop, and Fig. 3 shows the minor loop with a straight transfer path section and a 180° corner path section. FIG. 4 is an enlarged plan view of main parts showing an example of a minor loop related to the magnetic bubble memory chip according to the present invention, and FIG. 5 is an enlarged plan view of main parts showing an example of a minor loop related to the magnetic bubble memory chip according to the present invention. FIG. 6 is an enlarged plan view of the main part showing another embodiment of the present invention. FIG. 1... Minor loop, 1a... Straight transfer path section,
1b...180° corner path section, 1c...non-parallel linear transfer path section, 8, 9...asymmetric chevron pattern.

Claims (1)

[Claims] 1. In a magnetic bubble memory chip equipped with folded minor loops, mutually adjacent linear transfer portions of the minor loops have portions that are partially non-parallel to each other, and the non-parallel portions are arranged on the left and right sides. A magnetic bubble memory chip characterized by an array of asymmetric chevron patterns with different foot heights.