JP2000150685A - Electronic device protecting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable to detect machining of a case containing electronic devices from outside. SOLUTION: A protecting apparatus 11 for electronic devices comprises an upper case 12 and a lower case 14. Anomaly detecting plates 16 and 18 are integrally fixed to the inside of the upper case 12 and the lower case 14 respectively by insert molding. A circuit board 20 is contained in the lower case 14 and is fixed in such a way that its top is covered by the upper case 12. Semiconductor memory devices 22 such as memory chips or MPU's having memory areas as electronic devices are soldered onto the circuit board 20. A conductive pattern 24 is formed on the surface of the anomaly detecting plates 16 and 18. A specified current passes through the conductive pattern 24. When the conductive pattern 24 is cut by machining from the outside, the current is interrupted and anomaly detecting signals are outputted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protection device for an electronic device, which is externally processed in a case in which the electronic device is accommodated to prevent any operation on the internal electronic device.

[0002]

2. Description of the Related Art In a case in which, for example, a highly confidential electronic device is accommodated, it is usually configured to prevent the case lid from being opened and closed. On the other hand, in a case where a printed circuit board in which a semiconductor storage device (a memory chip having a storage area or an MPU or the like) in which software such as a control program is stored among electronic devices is accommodated, the semiconductor storage device is In order to prevent a stored program from being read, a protection device that destroys programs and data stored in the semiconductor storage device when the case lid is opened is incorporated.

[0003] As this protection device, for example, there is a configuration in which a contact between the lid and the case main body is separated and electrically detected when the lid of the case is opened. The protection device prevents an excessive voltage from being applied to a terminal of the semiconductor storage device based on the detection signal at that time to break a circuit inside the semiconductor storage device, thereby preventing a program or data from being stolen outside. It is configured as follows.

[0004]

However, in the above-described conventional protection device, the case is partially cut or a hole of about 3 to 4 mm is made in the surface of the case, and this signal reading probe is used. Since it can be inserted into the case, it was possible to read a program or data stored in the semiconductor storage device by bringing a signal reading probe into contact with a terminal of the semiconductor storage device without opening the case lid. .

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a protection device for an electronic device capable of detecting that a hole is formed in the surface of a case.

[0006]

Means for Solving the Problems To solve the above problems, the present invention has the following features. The invention according to claim 1 is characterized in that a substrate on which a predetermined conductive pattern is formed is fixed to an inner surface of a case accommodating an electronic device. Therefore, according to the first aspect of the present invention, the substrate on which the predetermined conductive pattern is formed is fixed to the inner surface of the case in which the electronic device is housed.
This can be detected.

According to a second aspect of the present invention, there is provided the electronic device protection device according to the first aspect, wherein the conductive pattern outputs a signal when the conductive pattern is drilled from the outside of the case. It is connected to a circuit and is supplied with electricity from the detection circuit.

Therefore, according to the second aspect of the present invention, the conductive pattern is connected to the detection circuit that outputs a signal when the conductive pattern is drilled from the outside of the case, and is supplied with electricity from the detection circuit. When a hole is opened in the case and the conductive pattern is cut, a signal is output from the detection circuit,
Based on this signal, the electronic device can be protected, or a program or data stored in the electronic device can be prevented from being stolen.

According to a third aspect of the present invention, in the electronic device protection device of the first aspect, the substrate is insert-molded when the case is molded. It is. Therefore, according to the third aspect of the present invention, when the case is molded, the substrate is insert-molded, so that the case and the substrate can be integrated, and if any processing is performed on the case surface from the outside, The substrate is also damaged together with the case, and the conductive pattern is cut, so that fraudulent acts can be reliably detected.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view of an embodiment of a protection device for an electronic device according to the present invention. As shown in FIG. 1, the protection device 11 of the electronic device includes an upper case 12,
This is a configuration combining the lower case 14 and the upper case 1
2 and an abnormality detection plate (substrate) 1 on the inner surface of the lower case 14
6, 18 are integrally fixed. This defense device 11
Is particularly used in highly confidential electronic devices, and is suitable for electronic devices that require security, such as a card reader / writer for an electronic money card.

The upper case 12 and the lower case 14 are made of synthetic resin, and the abnormality detecting plates 16 and 18 are insert-molded on the inner surfaces of the upper case 12 and the lower case 14. The circuit board 20 is accommodated in the lower case 14, and the upper part thereof is attached so as to be covered by the upper case 12. The abnormality detection plates 16 and 18 are formed in a box shape corresponding to the inner shapes of the upper case 12 and the lower case 14 formed in a box shape, and are integrated in a close contact state with almost no gap. .

A semiconductor memory device 22 such as a memory chip or an MPU having a storage area as an electronic device is soldered to the circuit board 20. In the semiconductor storage device 22, for example, a control program and various data are stored in a storage area. In addition, the abnormality detection plates 16 and 18
The base material is made of a relatively soft material so that molding can be easily performed, and its surface is coated with an insulating resist film.
4 are formed. A predetermined current is applied to the conductive pattern 24 as described later. When the conductive pattern 24 is cut by external processing, the current is cut off and an abnormality detection signal is output.

Incidentally, in the present embodiment, the abnormality detecting plate 16,
Although the configuration in which the conductive pattern 24 is formed on the inner surface of 18 is shown as an example, the invention is not limited thereto, and the abnormality detection plates 16 and 1
Of course, a configuration in which the conductive pattern 24 is formed on the outer surface of 8 may be adopted. FIG. 2 is a longitudinal sectional view of the protection device 11. FIG. 3 is a longitudinal sectional view taken along the line III-III in FIG.

As shown in FIGS. 2 and 3, the abnormality detecting plates 16 and 18 are locked by ribs 26 to 28 protruding from the inner surfaces of the upper case 12 and the lower case 14, and
2 and the lower case 14. Also, ribs 26-
28 is a small hole 16a penetrating the abnormality detection plates 16 and 18,
18a penetrating through 18a,
The abnormality detection plates 16 and 18 are locked so as not to fall off.

The circuit board 20 is fixed by screws 30 while being mounted on the upper end of the rib 28 of the lower case 14. The upper case 12 and the lower case 14 are fastened by screws 32 inserted into the ribs 26 and 28. The terminals of the conductive patterns 24 formed on the surfaces of the abnormality detection plates 16 and 18 are in contact with each other so as to be connected in series. For this reason, when the upper case 12 and the lower case 14 are separated from each other, the conductive patterns 24 are cut off and the energization is cut off.
Even if any one of the conductive patterns 24 is cut from the outside, both of them are attached so that they are disconnected.

FIG. 4 is a development view of the abnormality detection plates 16 and 18. As shown in FIG. 4, the abnormality detection plates 16 and 18 are
For example, a conductive pattern 24 is formed on a surface of a base material made of a metal substrate such as a copper plate, an aluminum plate, and an iron plate. The conductive pattern 24 is formed not only on the bottom surface or the top surface but also on each side surface in four directions.
It is formed in a portion excluding the small holes 16a and 18a penetrating the same. The conductive pattern 24 is provided on the abnormality detection plate 1.
6, 18 formed on either the inner surface or the outer surface.

When the base material is made of a metal substrate, the abnormality detecting plates 16 and 18 can be used even when X-rays are used.
Can not be determined, and a hole can be prevented from being formed in a portion where the conductive pattern 24 is not provided. further,
When the base material of the abnormality detection plates 16 and 18 is made of a metal substrate, it also functions as an electromagnetic shield, so that it is possible to shield external magnetism and protect electronic components such as the semiconductor memory device 22 from magnetism.

Further, the abnormality detecting plates 16 and 18 can be formed of a plastic substrate such as a glass epoxy resin or a polyimide resin. As described above, in the case where the conductive pattern 24 is formed of a plastic substrate, the surface of the conductive pattern 24 is coated in order to increase the adhesion between the upper case 12 and the lower case 14. The conductive pattern 24 is formed by continuously forming one conductive wire from one terminal 24a to the other terminal 24b in a zigzag manner. Even if one portion is cut, the conductive pattern 24 is disconnected and cannot be energized. Is formed. In addition, the conductive pattern 24 is formed such that the width and interval of each copper pad portion are about 0.1 to 0.5 mm.

Therefore, even if a hole having a diameter of 1 mm is formed from the outside of the conductive pattern 24, the conductive pattern 24 is cut off somewhere and cannot be energized. That is, the upper case 12 or the lower case 14
When a hole is made in the hole, a part of the conductive pattern 24 continuously formed at a fine pitch on the surfaces of the abnormality detection plates 16 and 18 is necessarily cut, and the potential difference between the terminals 24a and 24b becomes zero.

Thus, the upper case 12 or the lower case 1
4 can be detected from the outside, and the detection signal (zero voltage) can be output. Thus, by monitoring the voltage between the terminals 24a and 24b, it is possible to determine the presence or absence of an abnormality, so that the upper case 12 and the lower case 14 can be separated without separating the upper case 12 and the lower case 14.
In order to read the control program and each data stored in the semiconductor memory device 22 of the above, the upper case 12 or the lower case 14 is disconnected from the outside, or the upper case 1
At the time when the conductive pattern 24 is cut by making a hole in the second or lower case 14, the voltage applied to the conductive pattern 24 drops to zero, and abnormal processing from the outside is detected.

FIG. 5 is a block diagram of a protection circuit to which the conductive pattern 24 is connected. As shown in FIG. 5, the conductive patterns 24, 24 formed on the abnormality detection plates 16, 18
Are connected in series, the terminals of the conductive patterns 24, 24 are energized by the detection circuit 34 and the voltage value is monitored. The detection circuit 34 includes the conductive patterns 24, 24.
When the voltage becomes zero, a detection signal is output to the voltage application circuit 36. The voltage application circuit 36 applies an excessive voltage to the semiconductor storage device 22 based on the detection signal from the detection circuit 34 to destroy the program and data stored in the semiconductor storage device 22. This prevents programs and data stored in the semiconductor storage device 22 from being stolen outside.

Next, the upper case 12 or the lower case 14
Will be described in the order of each step. Upper case 12
The lower case 14 is molded by an injection molding machine. FIG. 6 is a front view showing a state before molding of a mold mounted on the injection molding machine. FIG. 7 is a front view showing a state after molding of a mold mounted on the injection molding machine. In step 1, the abnormality detection plates 16 and 18 on which the conductive patterns 24 are formed are prepared. In step 2, as shown in FIG.
6 (18) is loaded on the movable-side core plate 40. The abnormality detection plate 16 (18) is sucked by a vacuum (negative pressure) suction port (not shown) provided on the core 41 fixed to the core plate 40 and held at a predetermined insert position.

At this time, the core plate 40 is separated from the cavity plate 42, and the cavity plate 42 is separated from the fixed mounting plate 46 having the runner 44. In step 3, as shown in FIG. 7, the core plate 40 is driven in the direction B to move to a position where it contacts the cavity plate 42, and
Also moves to a position where it comes into contact with the fixed-side mounting plate 46. In step 4, molten resin is injected into the cavity 42 a of the cavity plate 42 from the runner 44 of the fixed-side mounting plate 46. Thus, since the abnormality detection plate 16 (18) is loaded in the cavity 42a, the molten resin is filled so as to cover the surface of the abnormality detection plate 16 (18). In step 5, the molten resin filled in the cavity 42a is cooled to solidify the molten resin in a state where the abnormality detection plate 16 (18) is insert-molded. Thus, the upper case 12 or the lower case 14 is obtained. In step 6, as shown in FIG. 6, the core plate 40 is driven in the direction A to move in a direction away from the cavity plate 42, and the cavity plate 42 is also separated from the fixed mounting plate 46. In step 7, the knockout plate 50 provided on the back side of the core 41 moves, and the knockout plate 5
The upper case 1 in which the knock pin 52 supported by the zero is molded.
The second or lower case 14 is separated from the core 41 and taken out of the mold.

As described above, the abnormality detection plates 16 and 18 can be easily integrated on the inner surfaces of the upper case 12 and the lower case 14 by insert molding using the injection molding machine. Therefore, the upper case 12, the lower case 1
When a process such as drilling or cutting is performed on 4, the conductive patterns 24 of the abnormality detection plates 16 and 18 integrated with the upper case 12 and the lower case 14 are cut, and abnormal processing from the outside is detected.

FIG. 8 is a longitudinal sectional view showing a modified example of the abnormality detection plates 16 and 18. As shown in FIG. 8, conductive patterns 24 are provided on both the inner and outer surfaces of the abnormality detection plates 16 and 18.
A and 24B are formed. In this case, the conductive pattern 24A on the inner surface and the conductive pattern 24B on the outer surface are formed in alternate positions.

As described above, when the conductive patterns 24A and 24B are formed on both surfaces of the abnormality detection plates 16 and 18, the other conductive patterns 24B are arranged at intervals between the conductive patterns 24A. The conductive patterns 24A and 24B are formed on the entire surfaces of the abnormality detection plates 16 and 18. Therefore, no matter where the holes are formed in the abnormality detection plates 16 and 18, the conductive pattern 24A or 24B is cut, and processing from the outside can be reliably detected.

In the above embodiment, the abnormality detecting plate 1
Although the inserts 6 and 18 are formed by insert molding and fixed integrally to the inner surfaces of the upper case 12 and the lower case 14, the present invention is not limited to this, and the abnormality detection plates 16 and 18 may be fixed by fixing means such as bonding. Of course, you can do so. Also,
In the above embodiment, the circuit board 20 is housed inside the upper case 12 and the lower case 14, but it goes without saying that the circuit board 20 has different shapes and configurations depending on the type of each device. .

[0028]

As described above, according to the first aspect of the present invention, since the substrate on which the predetermined conductive pattern is formed is fixed to the inner surface of the case accommodating the electronic device, a hole is formed in the case from the outside. Also, when the case is cut, the conductive pattern formed on the substrate fixed to the case is cut, and abnormal processing from the outside can be reliably detected.

According to the second aspect of the present invention, the conductive pattern is connected to the detection circuit that outputs a signal when the conductive pattern is drilled from the outside of the case, and is supplied with electricity from the detection circuit. When the hole is opened and the conductive pattern is cut, a signal is output from the detection circuit. Based on the signal, the electronic device can be protected, or programs or data stored in the electronic device can be prevented from being stolen.

According to the third aspect of the present invention, since the substrate is insert-molded when the case is molded, the case and the substrate can be easily integrated. Therefore, if any processing is applied to the case surface from outside,
The substrate is also damaged together with the case, and the conductive pattern is cut, so that fraudulent acts can be reliably detected.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an electronic device protection device according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the defense device 11.

FIG. 3 is a longitudinal sectional view taken along the line III-III in FIG. 2;

FIG. 4 is a development view of the abnormality detection plates 16 and 18.

FIG. 5 is a block diagram of a protection circuit to which a conductive pattern 24 is connected.

FIG. 6 is a front view showing a state before molding of a mold mounted on the injection molding machine.

FIG. 7 is a front view showing a state after molding of a mold mounted on the injection molding machine.

FIG. 8 is a longitudinal sectional view showing a modification of the abnormality detection plates 16 and 18.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Protective device 12 Upper case 14 Lower case 16, 18 Abnormality detection board 20 Circuit board 22 Semiconductor storage device 24 Conductive pattern 26-28 Rib 34 Detection circuit 36 Voltage application circuit 40 Core plate 41 Core 42 Cavity plate 46 Fixed side mounting plate 50 Knockout plate 52 Dowel pin

Claims (3)

[Claims] Claims: 1. An inner surface of a case accommodating an electronic device,
A protection device for an electronic device, wherein a substrate on which a predetermined conductive pattern is formed is fixed. 2. The protection device for an electronic device according to claim 1, wherein the conductive pattern is connected to a detection circuit that outputs a signal when a hole is drilled from the outside of the case, and the detection circuit is connected to the detection circuit. A protection device for an electronic device, wherein the device is energized from a terminal. 3. The protection device for an electronic device according to claim 1, wherein the substrate is insert-molded when the case is formed.