JPS6171491A - Manufacturing method of magnetic bubble device - Google Patents

Abstract

PURPOSE:To decrease widely a time needed to set the most suitable bias magnetic field value by installing a pilot loop of a narrower bias margin than that of other minor loop in a magnetic bubble device, in changing a magnetized quantity of a magnet for a bias magnetic field and detecting a margin of the bias magnetic field of the pilot loop. CONSTITUTION:A bias margin of a pilot loop Pm is intentionally set more narrowly than other minor loop (m). A bias magnetic field adjusting system is used, first, while a magnet of a magnetic bubble device is set to the maximum magnetization condition, a bias magnetic field is changed within a constant scope by a bias coil driver 6, information is written and read by a pilot loop Pm each in respective bias magnetic field value and an upper limit and a lower limit of the bias magnetic value, in which the pilot loop Pm goes to faulty, are retrieved. Thus, the object minor loop is decreased to plural pieces and the time needed to set the optimum bias magnetic value is widely reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a magnetic bubble device, and particularly to a method for setting an optimum bias magnetic field value in a step of magnetizing a bias magnetic field magnet.

The magnetic bubble device has a magnetic bubble chip and a
It is composed of a drive coil in the Y-axis direction, a bias coil and a magnet that apply a bias magnetic field.

As shown in the schematic diagram of FIG. 2, the storage area of the magnetic bubble chip includes a reading major line M1 equipped with a normal bubble generator Gl, a successive major line M2 equipped with a bubble detector S, and a minor line for reading bubbles. A swap or transfer gate G2 for entering the bubble into the loop, a replicate or transfer gate G3 for reading out bubbles from the minor loop, and about 300 or about 600 storage loops called minor loops m are formed. One information block (one page) is first introduced into the major line M1 from the bubble generator, and when this is in front of each gate G2, each gate is opened at the same time, and the information block is stored in the minor loop m. . When reading information in the minor loop m, when the information block comes in front of each gate G3, the gates are opened all at once and the information is transferred to the major line M2. This is major line M2
It is converted into an electrical signal by a bubble detector S installed in the bubble detector S.

In such a magnetic bubble device, there is a relationship shown in FIG. 3 between the bias magnetic field and the occurrence of defective loops. When the bias magnetic field of the magnetic bubble device increases beyond the optimal bias magnetic field value, the magnetic bubbles disappear and this phenomenon is called collapse), and when the bias magnetic field decreases beyond the optimal bias magnetic field value, the magnetic bubbles connect in a band shape (
This phenomenon is called strip-out). The width of the bias magnetic field that does not cause this collapse and strip-out, that is, the bias margin for the optimal bias magnetic field value is ±10
It is only as wide as Oersted (Oe).

On the other hand, the center value varies depending on the magnetic bubble chip, and even if you aim for around 210 oersted (Oe) as the target value, ±2
There is a "variation" of about 0 oersted (Oe), and there is also a "variation" between minor loops formed on the same magnetic bubble chip.

Therefore, the method of constructing a magnetic bubble device by combining a pre-magnetized bias magnetic field magnet with a magnetic bubble chip and other components has an extremely low yield. Therefore, it is necessary to detect the optimum bias magnetic field value for each magnetic bubble device and adjust the amount of magnetization of the magnet.

[Conventional technology]

As shown in FIG. 3, when the bias magnetic field passes a certain boundary, the number of defective loops from which information cannot be read increases rapidly, and eventually collapses or strips out. Therefore, as a method to set the optimal bias magnetic field value, information is written and read for each minor loop formed on the same magnetic bubble chip, and the upper and lower limits of the bias magnetic field value at which the number of defective loops begins to rapidly increase, that is, the bias A method is used to detect the margin and set the optimum bias magnetic field value.

Fig. 4 is a configuration diagram of a bias magnetic field adjustment system for doing this, which includes a system controller 1, a timing generator 2, an XY coil driver 3, a function driver 4, a sense verification circuit 5, and a bias coil driver 6.
, consists of an electromagnet power supply 7 and an electromagnet 8, and
The coil driver 3, function driver 4, sense verification circuit 5, and bias coil driver 6 are controlled via the timing generator 2, and the electromagnet power source 7 is directly controlled by the system controller 1. Then, the magnetic bubble device 9 is driven by the driver 3 and the function driver 4 in the XY coin, and the output signal of the magnetic bubble device 9 is read through the sense verification circuit 5 to determine whether the minor loop formed on the magnetic bubble chip is good or bad. are doing. The bias coil driver 6 is a circuit that controls the current flowing through the bias coil built into the magnetic bubble device 9, and can change the value of the bias magnetic field applied by the magnet within a certain range. Furthermore, by controlling the electromagnet power supply 7 to excite the electromagnet 8, the amount of magnetization of the magnet built into the magnetic bubble device 9 can be changed to a certain value.

First, magnetize the magnet of the magnetic bubble device to the maximum (5
50 Oe), the bias magnetic field value is changed within a certain range by the bias coil driver 6, information is written/read for each minor loop at each bias magnetic field value, and the bias magnetic field is set such that the number of defective loops begins to increase rapidly. Find the upper and lower bounds of a value. Next, the electromagnet power supply 7 is controlled to demagnetize the magnet, and the bias coil driver 6 similarly changes the bias magnetic field value within a certain range, and the upper and lower limits of the bias magnetic field value at which the number of defective loops begins to rapidly increase are searched. do. Demagnetization of the magnet and detection of the operating characteristics of the magnetic bubble device are repeated, and an optimum bias magnetic field value is set from the upper and lower limits of the bias magnetic field value.

[Problem that the invention seeks to solve]

Magnet attachment [300 to 60 pieces while changing 1
The method of writing/reading information for all minor loops, of which there are zero, and searching for the upper and lower limits of the bias magnetic field value requires a lot of time to set the optimal bias magnetic field value.

[Means for solving problems]

The above problem is solved by providing a pilot loop with a narrower bias margin than other minor loops in the magnetic bubble device, and detecting the bias magnetic field margin of the pilot loop while changing the amount of magnetization of the bias magnetic field magnet. is solved by the method of manufacturing a magnetic bubble device according to the present invention, which sets the optimum bias magnetic field value of the magnetic bubble device.

[Effect]

The writing/reading of information that was conventionally performed for all 300 to 600 minor loops is now possible by setting the optimum bias magnetic field value for the magnetic bubble device from the bias magnetic field margin of the pilot loop. The loops are reduced and the time required to set the optimum bias field value is significantly reduced.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic diagram showing an embodiment of the magnetic bubble chip according to the present invention.

There is a major line M1 in the storage area of the magnetic bubble chip.
and M2, and about 300 or about 60 pieces engaged therewith.
A memory loop called 0 minor loop m is formed.

A plurality of minor loops called a plurality of pilot loops Pm are placed at arbitrary positions of the minor loop m,
For example, they are distributed every 100 lines. The bias margin of pilot loop Pm is intentionally set narrower than other minor loops m, and the relationship between the bias margin of pilot loop Pm and the bias margin of other minor loops m, for example, pilot loop P
At the limit bias magnetic field value at which m becomes defective, the ratio at which other minor loops m become defective is experimentally determined in advance.

Therefore, by using the bias magnetic field adjustment system shown in Figure 4, we first magnetized the magnet of the magnetic bubble device to the maximum extent (
5500e) and bias coil driver 6.
The bias magnetic field value is changed within a certain range by , information is written/read for each pilot loop Pm at each bias magnetic field value, and the pilot loop Pm
Find the upper and lower limits of the bias magnetic field value at which the value becomes defective.

Pilot loop Pffl with bias magnetic field value in this range
If you cannot find the upper and lower limits of the bias magnetic field value that causes the failure, please refer to 1. The electromagnet power source 7 is controlled to demagnetize the magnet, and the bias coil driver 6 similarly changes the bias magnetic field value within a certain range, and information is written/read for each pilot loop Pm at each bias magnetic field value. , the upper and lower limits of the bias magnetic field value at which the pilot loop Pm becomes defective are searched.

This magnet demagnetization and the detection of the operating characteristics of the magnetic bubble device are repeated, and from the upper and lower limits of the bias magnetic field value for the pilot loop Pm, the upper and lower limits of the bias magnetic field value for the other minor loops m are calculated, and the magnetic Set the optimal bias magnetic field value for the bubble device.

In this way, the writing/reading of information for all 300 (IAI to 600 minor looses) was previously done, but now the optimum bias magnetic field value of the magnetic bubble device can be set from the bias magnetic field margin of the pilot loop. As a result, the number of target minor loops is reduced to a plurality, and the time required to set the optimum bias magnetic field value is significantly reduced.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a method for manufacturing a magnetic bubble device that significantly reduces the time required to set the optimum bias magnetic field value.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing an embodiment of the present invention, Fig. 2 is a schematic diagram showing an example of a conventional magnetic bubble chip, Fig. 3 is a diagram showing the relationship between a bias magnetic field and a generated defective loop, and Fig. 4 is a schematic diagram showing an example of a conventional magnetic bubble chip. The figure is a configuration diagram of a bias magnetic field adjustment system. ￥-l Dounken 2 Show (character. Figure 3 Fuen Lua Shiki! 4 songs

Claims (1)

[Claims] A pilot loop with a narrower bias margin than other minor loops is provided in the magnetic bubble device, and the bias magnetic field margin of the pilot loop is detected while changing the magnetization amount of the bias magnetic field magnet, and the magnetic bubble device A method for manufacturing a magnetic bubble device characterized by setting an optimal bias magnetic field value.