JPH0650332B2 - Abnormal condition detection system - Google Patents

Description

The present invention relates to an abnormal state detection system, and more particularly to an IC
The present invention relates to an abnormal state detection system suitable for an IC tester that inspects a package.

[Prior Art] In an IC tester, the number of test items and the number of tests tend to increase with the high integration of ICs to be tested. Therefore, the number of circuits inside the IC inspection unit (inspection head or the like) in the IC tester has increased, and the number of boards mounted thereon has increased. As a result, the board mounting becomes complicated and the situation is unavoidable unless it is densely packed.

By the way, since a power supply line runs on each board and power is supplied through this, when a circuit on the board has an abnormality, it is necessary to take measures against burnout.

As a measure against this, conventionally, the power line in the board is
By attaching the ED and visually observing the light emitting and extinguishing states of the ED, it is possible to detect a drop in the power supply voltage or a blown fuse,
Is power being supplied to the board normally?
I was deciding whether something went wrong.

[Problems to be Solved by the Invention] Generally, in an IC inspection unit that requires high-speed processing,
Since the logic is formed by using the ECL IC, the inspection unit is in a state in which the burnout accident is more likely to occur than ever before with the high integration of the IC to be tested.

That is, a matching resistor must be required for the connection between each IC. Two or more channels of power supply are required. Power consumption has increased. The fact that each circuit pattern is dense. And so on.

Therefore, it takes time to determine which board is in an abnormal state in a conventional system in which an LED is attached to a power supply line in a board and the power supply state is visually monitored by the LED. , There is a risk of overlooking.

[Object of the Invention] The present invention has been made in view of the above problems of the conventional technology, and solves the problems of the conventional technology and is abnormal in a simple and reliable manner. It is an object of the present invention to provide an abnormal state detection system capable of finding a substrate.

[Means for Solving Problems] Means of the present invention for achieving such an object include a monitor unit including an arithmetic processing unit and a memory, and a functional unit including a plurality of substrates on which various electronic circuits are mounted. , A display device, each board is provided with a fuse disconnection detection circuit for detecting disconnection of a fuse mounted therein, and the memory stores information about the board in correspondence with predetermined status information. Then, the monitor unit receives the signal from the fuse disconnection detection circuit of each board as status information and compares it with the predetermined status information stored in the memory to determine which board of the functional unit is in an abnormal state. Then, the process of displaying the information of the abnormal substrate on the display device is performed.

[Operation] With this configuration, even if the number of boards increases and the mounting density increases, it is possible to reliably and early detect which board has an abnormality, and centralize management. Becomes Then, the reliability and maintainability of the electronic device can be improved.

[Embodiment] An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram of an abnormal state detection system in an IC inspection unit to which the present invention is applied, and FIG. 2 (a) is a block diagram centering on the fuse disconnection detection circuit, and FIG. 2 (b). [FIG. 7] is an explanatory diagram of a mounting state of the board. 3A is a block diagram of another specific example centering on the fuse disconnection detection circuit, and FIG. 3B is an explanatory diagram of the mounting state of the board. In addition,
In each figure, the same parts are designated by the same reference numerals.

In FIG. 1, 1 is a monitor unit, which is an IC
It is installed in the control section of the tester. Reference numeral 2 is a display device (display) connected to the monitor unit 1 via a system bus 4, and 3 is an inspection head for detecting an IC, which is also connected to the monitor unit 1 via the system bus 4. It is connected.

Here, the monitor unit 1 includes an arithmetic processing unit 5, a memory 6, an interface 7, etc.
They are mutually connected via the local bus 1a. On the other hand, the inspection head 3 that inspects the IC includes a plurality of substrates 12 on which various electronic circuits including an inspection circuit are mounted.
Are arranged radially, for example, and
Fuse disconnection detection circuits 3a and 3b as shown in FIG. 2 are provided on each sheet.

Then, the fuse disconnection detection circuit 3 in each substrate 12
The a and 3b are connected to the comparators 8a and 8b mounted on the monitor board 13 mounted inside the inspection head 3 via the connection terminals of the connector 9, respectively.

Here, the outputs of the comparators 8a and 8b are input to the encoder 11 via the status register 10, coded, and sent as certain status information from the inspection head 3 to the monitor unit 1 via the system bus 4.

Here, the state register 10 is composed of, for example, FF circuits of the number arranged corresponding to each comparator, and stores the signals from each comparator 8a, 8b as flag information. It should be noted that when the coded status information has an 8-bit structure, it can represent 256 kinds of statuses, and if the power source of each board to be detected is one kind, the status of the 256 boards can be monitored.

Here, FIG. 2 (a) is an example in the case where two types of power supply voltages of + E and −E are required, and in FIG. 2 (a), the power supply voltage is connected to −E. The operation of the fuse disconnection detection circuit 3a on the upper side will be described. When the power is supplied in the normal state, the fuse FU1 is not disconnected, so the potential at the point becomes −E. Therefore, the detection input side of the comparator 8a has a potential of −E, which is lower than the reference potential −V (where V <E), and no detection output is generated in the comparator 8a. On the other hand, when an abnormality occurs in the circuit on the substrate 12 and the fuse FU1 is blown, the potential at the point becomes zero (ground potential), so the detection input side of the comparator 8a also becomes zero potential. At this time, the light emission of LED1 is also extinguished.

As a result, the LED 1 on the substrate 12 shown in FIG. 2B is turned off, the potential on the detection input side of the comparator 8a exceeds the reference potential, and the detection signal is generated from the comparator 8a.

This detection signal is stored as flag information "1" in the corresponding position of the status register 10 as a signal indicating a fuse disconnection. Then, such flag information corresponding to each comparator on each substrate 12 is provided to the encoder 1
1 is input and coded. As a result, state information is generated.

Here, this state information is sent to the monitor unit 1 at a predetermined timing and in a predetermined cycle, for example, with an interrupt signal.

In the fuse disconnection detection circuit 3b on the lower side of FIG. 2 (a),
In the case where the power supply voltage is + E, the reference voltage of the comparator 8b is + V (where V <E),
The operation is almost the same as the above except that the comparator 8b performs the inverting operation. Therefore, the explanation is omitted.

LED2 is a light emitting diode of the fuse disconnection detection circuit 3b, and D2 is a diode. Also, Ra,
Rb is a bias resistance of the comparators 8a and 8b, respectively.

The status information sent to the monitor unit 1 via the system bus 4 is accepted by the interface 7 of the monitor unit 1. Then, the arithmetic processing unit 5 samples this state information at an interrupt signal or at a predetermined cycle and stores it in a specific area of the memory 6. Next, the processor 5
By referring to the storage table on the memory 6, the predetermined status information and the sent status information are compared and judged. As a result, the abnormal state is determined, and as a result, when there is state information indicating a match on the storage table, the board information (board number or information indicating the board number and its position) in that column is searched, and this is searched. Read out and arithmetic processing unit 5
Transfers it to the display device 2 via the system bus 4.

In response to this information, the display device 2 displays on the display screen the number of the board or the position where the fuse has a broken wire.

In this way, it is possible to determine which substrate is in an abnormal state and the fuse is blown, and it is possible to easily detect the substrate in the abnormal state. Moreover, since the state of each substrate is processed by the state information, it is possible to centrally manage this with the monitor unit.

If none of the substrates is abnormal, a message to that effect is displayed. The status information in the case of no abnormality is determined by a logic circuit by allocating specific data, for example, all bits “1” and all bits “0”, or is determined with priority over other status information. The information retrieved when a match is found in this determination is information indicating that there is no abnormality.

FIG. 3A is a specific example of another fuse disconnection detection circuit corresponding to FIG. 2A, and detects not only the fuse disconnection but also the power supply voltage drop to some extent. it can.

The operation of the fuse disconnection detection circuit 3c on the upper side will be described. When the power supply is normally performed, the potential of the point becomes + E because the fuse FU2 is not disconnected. Then, the current of (E-ZD) / R1 is
0, the light receiving transistor Q2 is turned on, and a HIGH level voltage appears in the resistor R2. This is the normal state. ZD is a Zener diode D
It is the operating voltage of Z2.

On the other hand, when an abnormality occurs in the circuit on the substrate 12, the fuse F
When U2 is blown, the potential at the point becomes zero (earth potential), so that no current flows through the photocoupler 20. As a result, the light receiving transistor Q2 is turned off, and a LOW level voltage appears at the terminal of the resistor R2.

The fuse disconnection detection circuit 3d on the lower side of FIG.
In this case, the power supply voltage is -E, the operation is almost the same as the above, the light receiving transistor Q1 is in the "OFF" state, and a LOW level voltage appears at the terminal of the resistor R4. . Here, ZD1 indicates a Zener diode in the fuse disconnection detection circuit 3d, 21 is a photocoupler, and Q1 is its light receiving transistor. Further, R1, R2, R3 and R4 are resistors, respectively.

Here, the detection signals appearing at the terminals of the resistor R2 and the terminal of the resistor R4 are sent to the state register 10 provided on the monitor substrate 13 via the negative logic OR circuit 22. As a result, these LOW-level potentials are set in the corresponding status register 10 as detection signals. At this time, the light emission of the LED of the corresponding fuse disconnection detection circuit is extinguished.

Further, in such a detection circuit, the comparator is not necessary, and the resistor R2 is set according to the voltage drop on the power supply side.
Since the terminal voltage of the terminal or the terminal voltage of the resistor R4 drops, the detection signal can be generated depending on the setting condition even when a certain voltage drop occurs.

In this example, conversely to the case of FIG.
It becomes negative logic. In the case of matching with FIG. 2A, the LOW level detection signal appearing in the non-logical OR circuit 22 may be sent to the status register 10 via the inverter.

The arrangement of the fuse disconnection detection circuit in this case on the substrate 12 is as shown in FIG. 3 (b), for example.

As described above, the fuse disconnection detection circuit in the embodiment is an example, and it goes without saying that the present invention is not limited to this.

Further, although the display device is shown as a display device in the embodiment, this is not limited to the display by the display, for example, the LED corresponding to the substrate may be turned on or off on the LED display panel.
Further, a sound alarm may be generated together with such an abnormal display.

Furthermore, in the embodiment, the state information is periodically sent to the monitor unit side to judge the abnormal state.
This may be determined at any time according to a specific external signal.

In the embodiments, the example of the IC tester has been mainly described, but
The present invention is not limited to the IC tester, and it is needless to say that the present invention can be applied to various electronic devices in which substrates must be mounted at high density.

[Effects of the Invention] As can be understood from the above description, in the present invention, a monitor unit including an arithmetic processing unit and a memory, a functional unit including a plurality of boards on which various electronic circuits are mounted, and a display And a device, each board is provided with a fuse disconnection detection circuit for detecting disconnection of the fuse mounted therein, the memory stores information about the board corresponding to predetermined state information, The monitor unit receives the signal from the fuse disconnection detection circuit of each board as the status information and compares it with the predetermined status information stored in the memory to determine which board of the functional unit is in the abnormal state, Since the processing to display the information of the abnormal board on the display device is performed, even if the number of boards increases and the mounting density increases, it will be You can surely and early detect whether an abnormality has occurred,
The centralized management becomes possible. Then, the reliability and maintainability of the electronic device can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram of an abnormal state detection system in an IC inspection unit to which the present invention is applied, and FIG. 2 (a).
Is a block diagram centering on the fuse disconnection detection circuit, FIG. 2 (b) is an explanatory view of the mounting state of the board, and FIG. 3 (a) is another diagram centering on the fuse disconnection detection circuit. A block diagram of a specific example, FIG. 3 (b), is an explanatory view of the mounting state of the board. 1 is a monitor unit, 2 is a display device, 3 is an inspection head,
3a and 3b are fuse disconnection detection circuits, 4 is a system bus, 5 is an arithmetic processing unit, 6 is a memory, 7 is an interface, 8a and 8b are comparators, 9 is a connector, 10 is a status register, and 11 is an encoder.

Claims (2)

[Claims] 1. A monitor unit including an arithmetic processing unit and a memory, a functional unit including a plurality of substrates on which various electronic circuits are mounted, and a display device, each of which is mounted on the substrate. A fuse disconnection detection circuit for detecting a disconnection of a fuse is provided, information about a substrate is stored in the memory in correspondence with predetermined status information, and the monitor unit is configured to detect information from the fuse disconnection detection circuit of each substrate. A signal is accepted as status information, and it is determined which board of the functional unit is in an abnormal state by comparing with predetermined status information stored in the memory,
An abnormal state detection system, characterized by performing processing for displaying information on an abnormal substrate on the display device. 2. The abnormal state according to claim 1, wherein the functional unit is an IC inspection unit, and the monitor unit is provided in a control section for controlling the operation of the IC inspection unit. Detection system.