JPS583314B2 - jiki bubble memory soshi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic bubble memory device, and more particularly to a mechanism for eliminating noise signals from a signal obtained from a bubble detector.

In general, a magnetic bubble memory device (hereinafter referred to as a chip) has a circuit that controls the generation and erasure of bubble domains, a circuit that stores the bubble domain, a circuit that copies the bubble domain, and a circuit that detects the existence of the bubble domain and converts it into an electrical signal. It is equipped with a magnetic bubble detector that can be taken out.

As the above-mentioned magnetic bubble detector, one that utilizes the magnetoresistive effect of a soft ferromagnetic material such as permalloy has recently been used, as shown in FIG.

In the figure, 1 is a chevron-shaped transfer element made of permalloy or the like, 2 is a magnetic bubble detector made of permalloy or the like, and 3 is a magnetic bubble detector made of permalloy or the like.
is the magnetic bubble injection part.

FIGS. 2a and 2b are principle diagrams showing the mechanism for transferring bubble domains by the chevron transfer element 1, and the bubbles are A→
It is transferred via the route B→C→D→E.

Note that this bubble domain is transferred as the in-plane rotating magnetic field rotates clockwise from A→B→C→D→E as shown in FIG.

In this case, A-E in Figure 2a and A-E in Figure 2b are synchronized, and as a result, the bubble follows the rotation of the in-plane rotating magnetic field and is transferred bit by bit. .

The bubbles transferred based on this principle are
The bubbles are injected from the bubble injector 3 shown in the figure, transferred upward in the figure and expanded sequentially, and when they cross the detector 2, the sufficiently expanded bubbles create a sufficient magnetoresistive effect on the detector 2. , will be detected as an electrical signal.

A plurality of the above-mentioned chips are usually arranged in an X, Y drive coil that generates an in-plane rotating magnetic field, thereby obtaining a magnetic bubble memory device having a large storage capacity that is multiple times the storage capacity of one chip. be able to.

However, according to the conventional magnetic bubble memory device described above, the following problem occurs.

That is, the electric signal obtained from the detector 2 includes a noise signal due to the magnetoresistive effect based on the in-plane rotating magnetic field, in addition to a signal due to the magnetoresistive effect based on the leakage magnetic field of the bubble. There is a need to eliminate the noise signal from the signal obtained from the signal.

Various methods have been proposed in the past as means for erasing the above-mentioned noise signals.

First, if the chips are adjacent to each other on the same board on which multiple chips are mounted, or if multiple chips are mounted on multiple boards in the same coil, they are located at approximately the same geometric location on the upper and lower boards. A method has been proposed in which common-mode noise is differentially canceled by connecting detectors on similar chips to the positive and negative terminals of the same differential amplifier.

In other words, when detecting a bubble, the output signal of that detector is subtracted by the signal from the detector of another chip (a signal corresponding to noise obtained by detecting only an in-plane rotating magnetic field without detecting a magnetic bubble). There is.

Second, as shown in FIG. 3, a button (hereinafter referred to as a dummy detector) 2a that does not have a bubble injection unit 3, that is, is unrelated to the transfer of information bubbles, is provided in the same chip, and a regular detector 2 and a dummy detector are provided. 2a as the positive electrode of the same differential amplifier,
A method of connecting to the negative electrode has been proposed.

In the first method, at the timing when information is input to the detector of one chip among the noise canceling bears included in the same amplifier, information must never be present in the detector of the other chip.

That is, each chip has the disadvantage that it can only store or read information every other bit.

In the second method, a dummy detector 2a is used as shown in FIG.
Since the chevron transfer element 1 and the chevron transfer element 1 occupy a very large area like the regular detector 2 and the chevron transfer element 1, the bit density of the chip cannot be improved and the chip body is large. .

Therefore, an object of the present invention is to enable a chip to store information in arbitrary bits, to improve the bit density, and to make the chip itself and the device itself smaller. Explain in detail.

FIG. 4 is a plan view showing a chip constituting the magnetic bubble memory device according to the present invention, and the same parts as in FIGS. 1 and 3 are denoted by the same reference numerals.

In the figure, 2a is a dummy detector provided near the magnetic bubble injection section 3 and at the lowest stage of the chevron-shaped transfer element 1, and has the same configuration as the detector 2.

Reference numeral 4 denotes a button made of a chevron-shaped transfer element, and a portion thereof is thinned out at the lower end of the dummy detector 2a, so that the bubble is not expanded.

This pattern 4 is for making the magnetic ambient conditions of the dummy detector 2a the same as the ambient conditions of the detector 2.

The dummy detector 2a and the detector 2 are connected to the positive and negative electrodes of the differential amplifier, so that the output signal of the detector 2 is subtracted by the noise signal of the dummy detector.

In such a configuration, the output signal entered from the bubble injector 3 and detected by the detector 2 is subtracted by the noise signal, so a normal bubble output signal is obtained from the differential amplifier (not shown). be able to.

At this time of detection, even if a bubble following the above-mentioned bubble detected by the detector 2 arrives at the dummy detector 2a, this bubble is hardly enlarged and is detected by the in-plane rotating magnetic field from the dummy detector 2a. Only the noise signal can be obtained.

In other words, bubbles usually occur between 15 and 2 during the transfer of element 1.
At about the 0th stage, the image is magnified 200 to 300 times, so the dummy detector 2a hardly magnifies it.

Therefore, the present invention is completely irrelevant even if there is a subsequent bubble in the dummy detector 2a, and is effective even for a device with an extremely large storage capacity.

FIG. 5 is a plan view showing another embodiment of the chip of the magnetic bubble memory device according to the present invention, and the same parts as in FIG. 4 are designated by the same reference numerals.

In the figure, the dummy detector 2a is not provided at the lowest stage of the chevron-shaped transfer element 1, but is provided across a narrow guide pattern 5 provided for guiding bubbles to the bubble injection section 3. .

On both sides of this dummy detector 2a, pads 4, 4a are provided to set the same conditions as the surroundings of the detector 2.

Note that the dummy detector 2a and the detector 2 are connected to the positive and negative electrodes of a differential amplifier (not shown).

According to such a configuration, the bubble is hardly enlarged in the dummy detector 2a, so that a more accurate signal can be obtained.

As explained above, according to the magnetic bubble memory device according to the present invention, a dummy detector having almost the same configuration as the above detector is provided in the portion where the bubble is not expanded while the bubble is being transferred to the detector. Since the output signal from the above detector is subtracted by the signal from
A regular bubble signal can be obtained.

Moreover, according to the present invention, the subsequent bubble is detected by the dummy detector 2.
Even when the bubble reaches point a, no signal is generated in the dummy detector due to the subsequent bubble, so the bubble signal is extremely accurate.Moreover, since the area occupied by the dummy detector 2a or the entire batten attached to it is small, the bit density is This has the effect that the chip and the device itself can be made smaller.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing a conventional magnetic bubble memory element, in particular the vicinity of a bubble detector, Figs. 2 a and b are plan views for explaining the bubble transfer mechanism, and Fig. 3 is a plan view of a conventional magnetic bubble memory element. FIGS. 4 and 5 are plan views showing the vicinity of a magnetic bubble memory element, particularly a bubble detector, according to the present invention. FIGS. 1...--Chevron transfer element, 2... Regular magnetic bubble detector, 2a... Dummy detector, 3...
...Bubble injection part, 4, 4a...Bang, 5...Guidance bang.

Claims (1)

[Scope of Claims] 1. A magnetic bubble detector, a magnetic bubble injector provided in the magnetic bubble detector, and a magnetic bubble injector provided in a magnetic bubble transfer path that divides the bubble domain during the transfer to In a magnetic bubble memory element having a replicator that sends out the bubble to the bubble injection section, a dummy detector having almost the same configuration as the magnetic bubble detector is installed in a portion of the bubble domain that is not expanded while the bubble domain is being transferred to the magnetic bubble detector. 1. A magnetic bubble memory element characterized in that the output signal from the magnetic bubble detector is subtracted by the signal from the dummy detector. 2. In the magnetic bubble memory device according to claim 1, a bubble transfer button similar to the bubble transfer button formed near the magnetic bubble detector is provided around the dummy detector so that the bubble domain is not expanded. A magnetic bubble memory element characterized by: