JPS6163993A - Magnetic bubble memory detector - Google Patents

Abstract

PURPOSE:To improve bubble transfer characteristics by using two types of cell patterns to constitute a magnifier. CONSTITUTION:Magnifiers 7, 4', 4' and 4 are formed with cell patterns 1c, 1b', 1b' and 1b where the pattern cycles are increased gradually up to the 4-fold length from the 2-fold length. These magnifiers are arrayed along the transfer direction P of magnetic bubbles an in a range up to a detector line 5. While magnifiers 3 and 7 consisting of cell patterns 1a and 1c where the pattern cycles are reduced down to the 2-fold length from the 4-fold length are provided along the direction P of the line 5. Bubbles are transferred satisfactorily up to the magnifier 4 consisting of a pattern 1b of a 4-fold length cycle lambdasb for suppression of nearby bubble noises set immediately before the line 5 via the magnifier 7 and then to the line 5. Then these bubbles are detected 5 and absorbed by the magnifier 3 consisting of the pattern 1a of a 4-fold length cycle lambdasa at the exit of the line 5. The absorbed bubbles are transferred in the direction P.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a magnetic bubble memory detector, and particularly to a magnetic bubble memory detector in which the magnetic bubble transfer characteristics of an expander forming a part of the detector are improved. Zek 1 [Background of the invention] The detector of a magnetic bubble memory element is composed of a magnifying device made of a soft magnetic metal pattern and a detector line, and in most cases, the magnifying device and the detector line are manufactured using the same process. A thick film type detector is used. This detector is the part that detects magnetic bubble information, and when the magnetic bubble is stretched into a string several hundred times the length using a magnifier and passes under the detector line, an electrical signal is generated that detects the change in magnetic resistance. to determine the presence or absence of magnetic bubbles.

As the capacity of magnetic bubble memory devices increases, there is a demand for faster data read speeds. In response to this demand, the conventional detection method was to read out data once every two rotations of the rotating magnetic field, but a method of reading out once every rotation of the rotating magnetic field (hereinafter referred to as bit-by-bit reading) has been adopted. According to this bit-by-bit reading, a data read speed of 2@ can be obtained at the same rotating magnetic field frequency.

However, in the case of bit-by-bit readout, since there is always a magnetic bubble in the magnifier immediately before or after the detector line, the detector line receives the shadow 8 of the magnetic bubble immediately before or after this, causing noise in the detection output. (hereinafter referred to as proximity bubble noise) is known to occur. In order to suppress this proximity bubble noise, a method has been considered to extend the magnetic bubbles from the detector line, and therefore the cell pattern period of the magnifiers immediately before and after the detector line is lengthened.

1(a) + (b+), (C) is an enlarged plan view showing an example of an expander cell pattern, and FIG. 1(d) is an enlarged plan view showing an example of a transfer path pattern. : Expander cell pattern for reading every missing bit, the same figure (c) is 1
Each is used for an expander cell pattern for bit-by-bit readout. In the same figure, in order to suppress the aforementioned proximity bubble noise, each period λSa+λsb of the expander cell patterns Ia and 1b shown in FIGS. 4 times the period λ,
That is, it is formed with a period λSa + λ5b = 4λ, and on the other hand,
The period λs0 of the expander cell pattern 1C shown in FIG.
is formed by approximately 2λ (λSC≧2λ).

Figures 2 and 3 show the above-mentioned j-th bit readout.
FIG. 2 is an enlarged plan view of a main part of an example of a magnetic bubble detector using a double-period expander cell pattern. In these figures, 3 and 4 are enlargers each consisting of the enlarger cell patterns Ia and 1b shown in FIGS. It is a continuous bubble in case. In addition, Id is the current for detecting 8 bubbles flowing in the direction of the arrow in the detector line 5, HB is the bias magnetic field applied from the back of the paper to the front, HR is the rotating magnetic field applied counterclockwise to the paper, and P is the transfer direction of continuous bubbles 6a, 6b, and 6e.

However, in the magnetic bubble detector configured in this way, the expander 3 shown in FIG. 2 has a cell pattern 1a with a large width ta and a pattern period λ, as shown in FIG.
Since Sa has a long period of 4 times, continuous bubble $ a
Although the transfer characteristics between the gears G of + 5 b - + 6 c are good, there is a problem in that the magnetic bubbles are stretched in the central portion of the pattern 1a and the transfer characteristics thereof are relatively poor. On the other hand, in the expander 4 shown in FIG. 3, since the cell pattern 1b is formed with a large curvature, the magnetic bubbles in the central part of the pattern 1b have good stretching and transfer characteristics. bubbles 6a, 6b
, 6C has a problem in that the transfer characteristics between the gears G are inferior to those of the enlarger 3 shown in FIG. 2 described above.

Configuring a quadruple length period expander for reading each bit with good transfer characteristics using a single cell pattern is as follows:
Since each cell pattern has a transfer characteristic of 'Jl 6't, it has the drawback of being extremely difficult and unreliable.

[Purpose of the invention]

Therefore, the present invention has been made in view of the above-mentioned conventional drawbacks, and an object thereof is to provide a magnetic bubble memory device having an enlarger with good magnetic bubble transfer characteristics.

[Summary of the invention]

To achieve this objective, the present invention provides an expander configured using at least 2, f, and lrf cell patterns. It is something that That is, a magnetic bubble detector is constructed by using a pattern with good magnetic bubble transfer characteristics up to the entrance of the detector line, and using a pattern with good transfer characteristics between gaps at the exit of the detection line.

[Embodiments of the invention]

Next, embodiments of the present invention will be described in detail using the drawings.

FIG. 4 is a plan view of essential parts showing an example of a magnetic bubble memory detector according to the present invention, and since the same symbols as those in the previous figure represent the same elements, a description thereof will be omitted. In the figure, immediately before the detector line 5, that is, from staying in the magnetic bubble transfer direction P until reaching the detector line 5, the pattern period is gradually expanded from twice the length to four times the length. Each cell pattern Ic, 1 b'', 1b', 1
The enlargers 7° 4'', 4', 4 consisting of b are arranged. In this case, the enlarger 4''.

4' Each of the cell patterns 1b', 1b'c, which constitutes the entire cell pattern, has a curvature equivalent to that of the cell pattern 1b, which has good magnetic bubble transfer characteristics, in the central part of the pattern, and only the period thereof is reduced. Each expander 714''+4'14 has its pattern circumference 1111 arranged in the r66 bubble transfer direction P with different butter/periods in the order of size λsc<λsb''<λsb'<λSb. has been done. on the other hand,
Immediately after the detector line 5, that is, along the magnetic bubble transfer direction P of the detector line 5, the pattern period is 4 to 2.
Enlargers 3 and 7 each consisting of cell patterns Ia and Ic reduced to double length are provided.

In the magnetic bubble detector configured in this way, the magnetic bubbles transferred to the expander 7 before the detector line 5 are transferred to the expander 7 consisting of the cell pattern 1C with double length period λSc and having good transfer characteristics. After being sufficiently stretched, IFi is installed with a 4-inch expander consisting of a cell pattern 1b with a 4-length expansion period λsb for suppressing adjacent bubble noise just before the detector line 5.
When the magnetic bubble is successfully transferred and further transferred to the detector line 5, the magnetic bubble is detected by the detector line 5, and at the exit of the detection line 5, the cell pattern 1a with the quadruple length period λSa is also formed by the expander 3. is attracted and transferred in the direction of arrow P. That is, at the exit of the detector line 5,
As shown in FIG. 5, the magnetic bubble repulsion field weakens due to the influence of the current passage section 5a connecting between the chevron patterns of the detector line 5, and this is the section where the transfer/returnability is the lowest. It is expected that the gap transfer characteristic at the exit of the detector line 5 will be significantly reduced in inverse proportion to the increase in the density of the bubble memory element as the magnetic bubble diameter becomes smaller and the saturation magnetization 4πMs becomes larger. Therefore, the fourth
As shown in FIG. 6, which is a partially enlarged view, the pattern width ta
Due to the expander cell pattern 1a, which is thick and has a quadruple long period,
The attractive magnetic pole of the magnetic bubble is strengthened, thus improving the gear-to-gear transfer.

〔Effect of the invention〕

As explained above, according to the present invention, the gap transfer between the quadruple period expander cell patterns and the gap transfer at the exit of the detector line, which had conventionally had poor transfer characteristics, are improved, so the magnetic bubble transfer characteristics are improved. Moreover, an extremely excellent effect can be obtained in that a detector for reading every bit without adjacent bubble noise can be realized.

[Brief explanation of the drawing]

1 to 3 are diagrams for explaining an example of a conventional magnetic bubble detector, FIG. 4 is a plan view of essential parts showing an example of a magnetic bubble detector according to the present invention, and FIGS. The figure is an enlarged plan view of the main part for explaining the operation of the magnetic bubble memory detector according to the present invention. 1a, 1b, 1c... Magnifier cell pattern, 2...
... Transfer path pattern, 3, 4... Enlarger, 5...
・Detector line, 6a+6b+6c...magnetic bubble, 7...magnifier. , - Patent Attorney Akio Ko] Figure 1 ((1) (b) (C) (d) Figure 2IA Figure 3 Figure 4

Claims (1)

[Claims] 1. A magnetic bubble memory detector comprising a magnetic bubble expander before and after a detector line for detecting the presence or absence of a magnetic bubble, wherein the expander is composed of at least two different cell patterns. A magnetic bubble memory detector characterized by: 2. The expander has a transfer path with a cycle that is four times as long, and the cell pattern immediately before the detector line has a pattern width equivalent to the gap between the patterns, and the cell pattern immediately after the detector line has a width twice that of the gap. 2. The magnetic bubble memory detector according to claim 1, wherein the magnetic bubble memory detector has a pattern width of .