JPS607686A - Magnetic bubble memory device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a magnetic bubble memory device (hereinafter simply referred to as "pull memory"), and particularly to a two-arm cage structure thereof.

Technical background A bubble memory with a storage capacity of 1Mbit using a major/minor loop configuration has already been developed.
Furthermore, there is a demand for the development of a bubble memory with a high storage capacity of 4 Mbit or more. As a method to achieve such a high storage capacity, we use the same circuit configuration as the existing 1Mbit bubble memory, but set the bubble diameter to 'A', and double the storage capacity (bits) per information storage loop (minor loop). A possible method is to double the pitch V2) and double the number of information storage loops once a month. However, this method requires a highly accurate fine lithography technique to form the bubble transfer path, and has the problem of doubling the access time.

On the other hand, from a system perspective, compatibility with the existing IMbit bubble memory is also required.

From the above points, it is currently considered that the most suitable 4 Mbit bubble memory is a configuration in which four existing IMbtt bubble memory chips are arranged in parallel and reduced to a smaller size.

However, in this configuration, the number of external connection terminals is IMb.
A problem arises in that the number of terminals increases by four times compared to the IT bubble memory, and even if some of the terminals are made common, the number increases by more than two times.

However, the conventional bubble memory cage structure cannot handle such a large number of terminals, as will be described later.
Countermeasures are required.

Prior Art and Problems The package structure of a conventional puzzle memory will be explained with reference to the drawings. Figures 1 and 2 show the conventional I Mbit
FIG. 2 is a perspective external view and an exploded view of an example of a bubble memory. In the figure, reference numeral 1 indicates a memory main body, and reference numeral 2 indicates a case for magnetic shielding of the memory main body. Referring to Figure 2,
Bubble memory chip 3 is mounted on ceramic substrate 4,
Furthermore, two coils 5 that are directly fired with each other for generating an in-plane rotational driving field.
, 6 are assembled on the substrate 4 to form a chip/coil assembly 7.
is made. This assembly 7 is mounted on a resin molded rack 1/-m 9 provided with external connection terminals 8, and from above and below on the east are keyo'1'-10, 11 and permanent magnets 12 and 13 for generating a magnetic field. Then, the memory main body 1 is assembled. On the other hand, the magnetic shield case 2 is made of magnetic material (
It has a cylindrical shape with both ends open and is made of, for example, permalloy, and is fitted into the memory main body 1 from the direction of arrow A.

However, with such a conventional magnetic shield case structure, the terminals 8 can only be provided on two opposing sides of the frame 9, so it cannot be applied to a 4 Mbit puzzle memory that requires a large number of terminals as described above. .

OBJECTS OF THE INVENTION In view of the above-mentioned circumstances, an object of the present invention is to provide a package structure for a magnetic bubble memory device in which one or more terminals can be provided than in the past.

Structure of the Invention The magnetic bubble memory device according to the present invention has a memory main body made up of a puzzle memory chip assembled with a coil for generating a magnetic field, a permanent cornerstone, and an external connection terminal, and a magnetic shield plate is placed on the top and bottom surfaces of the memory main body, respectively. The shield plate is connected and fixed only at the corner portion of the memory main body, and the external connection terminals can be drawn out from three or more sides of the memory main body.

Embodiments of the Invention Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

3 and 4 are a perspective external view and a partially exploded view of an embodiment of a 4 Mbit bubble memory according to the present invention. In the figure, numeral 21 indicates the entire memory main body, and numeral 22 indicates a magnetic shielding case. The memory main body 21 is basically a chip/coil assembly in which a bubble memory chip and a driving magnetic field generating coil are assembled on a ceramic base plate in a resin mold frame, similar to the memory main body 1 of the conventional 1 Mbit puzzle memory shown in FIG. Assemble it, and add the keeper to it.
and a permanent arsenite for generating a bias magnetic field, but as will be described later, the structure of the chip/coil assembly and the arrangement of the outside +419 pins are different.

The magnetic shield case 22 consists of a pair of upper and lower magnetic shield plates 22A and 22B, particularly as shown in FIG. Each shield plate 22A, 22B is basically the same size as the memory main body 21, but each
It has projecting pieces 22a and 22b at the corners. Shield plate 2
2A and 2213U are respectively placed on the upper and lower surfaces of the memory book V+21, and the protrusions 22a and 22b at the four corners are completely folded and overlapped to form a single remainder, so that they are magnetically connected to each other and are structurally connected. The magnetic shield case 22 is also fixedly held. In addition, the shield temporary projecting pieces 22a at the four corners,
It has been experimentally proven that good external magnetic field resistance characteristics of the shield case 22 can be obtained only by joining 22b.

However, in order to prevent characteristic deterioration due to bending of the 7-shaped plate protrusions 22A and 22b, it is effective to heat-treat them at about 200° C. after bending J-forming.

With such a magnetic field case configuration, 1'-!
(As shown, the four sides of the memory main body are opened, and it becomes possible to pull out 28 phase terminals from the open side sides to the external connection by 1 degree, as shown in Figs. 1 and 2. Compared to the conventional non-cage structure shown in Figure 1, approximately twice the number of terminals can be used.

In addition, in order to pull out the terminal 28 from the 40,000 side of the memory body 21 as described above, the coil/chi.

The assembly may have a structure as shown in FIG.

That is, four protrusions 24 are provided on the ceramic substrate 24 as shown in the figure.
a, 24b, 24c, 24d,
A bubble memory chip f23 and drive magnetic field generation coils 25 and 26 are mounted on this, and the board protrusions 24a, 24b, 24
An electrical connection is made with the node 28 at c and 24d.

Effects of the Invention As described above, according to the package structure of the present invention, it is possible to draw out a large number of external connection terminals from the memory main body by simply improving the structure of the magnetic shielding case. This can contribute to the realization of a 4Mbit bubble memory.

[Brief explanation of drawings]

1 and 2 are a perspective external view and an exploded view of an example of a conventional I Mbit bubble memory, and FIGS. 3, 4, and 5.
The figures are a perspective external view, a partially exploded view, and an exploded view of a chip/coil assembly of an embodiment of a 4 Mbit bubble memory according to the present invention. 21...Memory body, 22...Magnetic shield case, 22A, 22B...Magnetic shield plate, 22a, 22b
...Shield and projecting piece, 23...Magnetic puzzle memory chip, 24...Ceramic substrate, 25.26...1
n1 Internal rotation drive magnetic field generation coil, 28...Terminal for external contact. Patent applicant Fujitsu Limited Patent agent Akira Aoki Patent attorney Kazuyuki Nishidate Patent attorney 1) Yukio Patent attorney Akira Yamaguchi Figure 1 Figure 4 Figure 5

Claims (1)

[Claims] 1. The memory body, which is made up of a puzzle memory chip assembled with a coil for generating a magnetic field, a permanent magnet, and a terminal for external connection, is covered with magnetic shield plates on the top and bottom surfaces respectively, and both seal plates are attached to the corners of the memory body. 1. A magnetic noggle memory device, characterized in that the connection is fixed with a chisel, and the external connection terminals can be pulled out from three or more sides of the memory main body.