JPH03233366A - Voltage monitoring device - Google Patents

Abstract

PURPOSE:To easily monitor potentials of all voltage monitoring points regardless of the number of voltage monitoring points by detecting that a specified 1st signal is inputted to at least one among plural input terminals and allowing it to generate a 2nd signal. CONSTITUTION:When every potential of voltage monitoring points inputted to two voltage comparator circuits 10a, 10b are less than the allowable maxi mum potential, an L-level is outputted from output terminals 19 by both circuits 10a, 10b. The L is also output from an output terminal 29 accordingly. On the other hand, in the circuits 10a, 10b, when either one at least among the potentials of each inputted voltage monitoring point exceeds the allowable maximum potential, the H-level is output from the output terminals 19 of circuits 10a, 10b in the manner of changing-over a relay by a comparator. The output terminals of two circuits 10a,10b are all connected to the input terminals of a detecting circuit 20. Therefore, the H-level is output from the output termi nal of the detecting circuit 20 even if the H is outputted from any output termi nal 19 of the circuits 10a, 10b. Consequently, an abnormality of semiconductor device can be detected by detecting that the output is changed to the H from L-level.

Description

[Detailed Description of the Invention] [Summary] This invention relates to a voltage monitoring device that monitors the potential of each part of a monitored device, such as a semiconductor device, and immediately detects any fluctuation when it occurs. The object of the present invention is to provide a voltage monitoring device that can easily monitor the potentials of all voltage monitoring points regardless of the number, and has a first and second input terminal and an output terminal, and has a first and second input terminal and an output terminal. It is detected that the potential of the voltage monitoring point input to the input terminal of the second input terminal exceeds (below) the allowable potential in the steady state of the voltage monitoring point input to the second input terminal, and a plurality of voltage comparison circuits that generate a first signal; and a plurality of input terminals to which the output terminals of the plurality of voltage comparison circuits are respectively connected;
one output terminal, and detects that the predetermined first signal is input to at least one of the plurality of input terminals, and generates a predetermined second signal from the output terminal. and a detection circuit.

[Industrial application field]

The present invention relates to a voltage monitoring device that monitors the potential of various parts of a monitored device, such as a semiconductor device, and immediately detects a fluctuation when it occurs.

As the performance of various devices has improved in recent years, there has also been a demand for improved reliability of the devices.

For example, in the development of semiconductor devices, durability tests are also conducted to ensure that characteristic fluctuations do not occur over a long period of time. However, in the unlikely event that a change in characteristics occurs during a test, etc., it is necessary to immediately detect and deal with this change.

[Conventional technology]

For this reason, conventionally, characteristics have been monitored by regularly measuring the potential of each part of a semiconductor device or the like. By confirming that a fluctuation has occurred in the monitoring potential, it is detected that an abnormality has occurred in the device.

[Problem to be solved by the invention]

However, as the number of voltage monitoring points for semiconductor devices increases as the semiconductor devices become more sophisticated and demand for improved reliability, it becomes extremely difficult to measure the potential at a large number of voltage monitoring points at the same time. It has become a lot of work.

An object of the present invention is to provide a voltage monitoring device that can easily monitor the potentials of all voltage monitoring points, regardless of the number of voltage monitoring points of a monitored device.

[Means to solve the problem]

FIG. 1 is a diagram of the basic principle of the present invention.

In the figure, 10 is a voltage comparison circuit, 1a and 1b are both input terminals of the voltage comparison circuit 10, 1a is a terminal for connecting to a voltage monitoring point of a semiconductor device to be monitored and inputting its potential, and 1b is a terminal for connecting to a voltage monitoring point of a semiconductor device to be monitored and inputting its potential. This is for inputting the allowable potential at the voltage monitoring point.

19 is an output terminal of the voltage comparison circuit 10. Further, 20 is a detection circuit for detecting a change in the output of the voltage comparison circuit 10, and 2 is a plurality of input terminals in the detection circuit 20, to which output terminals 19 of different voltage comparison circuits 10 are connected. It is. 29 is an output terminal of the detection circuit.

In order to achieve the above object, the present invention has first and second input terminals and an output terminal, and the potential of the voltage monitoring point input to the first input terminal is applied to the second input terminal. a plurality of voltage comparator circuits that detect that the input voltage exceeds (below) an allowable potential in a steady state of the voltage monitoring point and generates a predetermined first signal from the output terminal; The comparator circuit has a plurality of input terminals and one output terminal, each of which is connected to an output terminal, and the predetermined first signal is input to at least one of the plurality of input terminals. and a detection circuit that detects the signal and generates a predetermined second signal from the output terminal.

[Effect]

The voltage monitoring device of the present invention has as many voltage comparison circuits as the number of voltage monitoring points that input the potentials at the voltage monitoring points, and is configured in correspondence with the number of voltage monitoring points of the monitored device. All of the output terminals of the voltage comparison circuit are input to the detection circuit to obtain a single final output signal.

In the present invention, when the potential of the voltage monitoring point input to one of the two input terminals in the voltage comparison circuit exceeds (below) the allowable potential of the voltage monitoring point input to the other, the voltage comparison circuit outputs the output terminal. A predetermined first signal is generated.

All the output terminals of the plurality of voltage comparison circuits are connected to the detection circuit, and when the predetermined first signal is output from the output terminal of at least one voltage comparison circuit, the output terminal of the detection circuit A predetermined second signal is output.

Therefore, in the voltage monitoring device of the present invention, the number of signals actually monitored is only the signal of the detection circuit, regardless of the number of voltage monitoring points in the monitored device, so monitoring of the voltage of the monitored device is greatly simplified. It will be transformed into

〔Example〕

FIG. 2 is a circuit diagram showing an example of a voltage comparison circuit according to the present invention, and the same parts as in FIG. 1 are designated by the same symbols.

4 in the figure is a comparator IC for voltage comparison, which outputs a low voltage (hereinafter referred to as "L") when a high voltage (hereinafter referred to as "rH") is input to the input terminal 1a on the negative side.
Conversely, when rH is input to the input terminal 1b on the positive side, "H" is output. Further, 5 is an application terminal, which always supplies a constant voltage. 7 is relay 3a, 3b
are an NC terminal and a No terminal, respectively, and the NC terminal 3a
In the steady state (state B where the relay is not operating), the relay 7 supplies "L" to the output terminal 19, and the No. terminal 3
When the relay 7 is in operation, the relay 7 supplies rH from the application terminal 5 to the output terminal 19.

Next, the operation of this circuit will be explained in detail.

When a voltage higher than that of the first input terminal 1a is input to the second input terminal 1b, the comparator IC4 outputs "I" because the second input terminal 1b is a positive terminal. Since "H" is always supplied from the signal application terminal 5, the relay 7 does not operate and remains in a steady state. Therefore, the output terminal 19 has rL and
is output.

On the other hand, if a voltage higher than that of the second input terminal 1b is input to the first input terminal 1a, the comparator IC4 becomes "L" because the first input terminal 1a is a negative terminal.
Output. Then, since the voltage applied to the application terminal 5 becomes higher than the output voltage of the comparator IC4, the relay 7 operates and the output terminal 19 is connected to the No terminal 3b. Therefore, rH is outputted from the application terminal 5 to the output terminal 19 by the No terminal.

That is, in this circuit, if the voltage input to the second input terminal 1a is higher than the voltage input to the first input terminal 1b, "L" is set, and in the opposite case, "H" is set. It is output from the output terminal 19.

FIG. 3 is a circuit diagram showing an example of a detection circuit according to the present invention, and the same parts as in FIG. 2 are designated by the same symbols.

Although this example has two input terminals 2, it has a similar configuration to the voltage comparison circuit 10 and can be easily configured. Further, the two input terminals 2 are referred to as first and second input terminals 2a and 2b, respectively, for distinction.

The operation of this circuit will be explained in detail below.

When a voltage higher than that of the first input terminal 2a is input to the second input terminal 2b, the comparator TC4 outputs rl(J. Since "H" is always supplied from the terminal 5, the relay 7 does not operate and remains in a steady state.Therefore, the output terminal 29 receives the voltage input to the second input terminal 2b by the NC terminal 3a. It will be output as is.

On the other hand, if a voltage higher than that of the second input terminal 2b is input to the first input terminal 2a, the comparator IC4 becomes "L" because the first input terminal 2a is a negative terminal.
Output. Then, since the voltage applied to the application terminal 5 becomes higher than the output voltage of the comparator IC 4, the relay 7 operates and the output terminal 29 is connected to the No terminal 3b. Therefore, the voltage input to the first input terminal 2a through the No terminal is directly output to the output terminal 29.

That is, in this circuit, the first and second input terminals 2a, 2b
Output terminal 29 always outputs the higher voltage of the input voltage.
Output from

FIG. 4 is an explanatory diagram showing one embodiment of the present invention, and shows a voltage monitoring device composed of two voltage comparison circuits IO and a detection circuit 20 connected thereto.

Components in the figure that are the same as those in FIGS. 2 and 3 are indicated by the same reference numerals, but in order to distinguish between the two voltage comparison circuits, they are referred to as first and second voltage comparison circuits 10a and 10b. Further, 6 is a detection terminal, which is used to determine which voltage comparison circuit outputs a predetermined first signal.

This embodiment monitors the potentials at two voltage monitoring points set in a monitored device, for example, a semiconductor device.

Therefore, in response to this, the voltage monitoring device of this embodiment has two
Voltage comparison circuits 10a and 10b are used, and their respective outputs are combined into one output by a detection circuit 20.

First input terminal 1a in first voltage comparison circuit 10a
is supplied with the potential of one of the two voltage monitoring points, and the second input terminal 1b is supplied with the maximum allowable potential at the voltage monitoring point from, for example, a constant voltage source. .

In the second voltage comparison circuit 10b, the potential of the other voltage monitoring point and its maximum allowable potential are similarly input to the first and second input terminals 1a and 1b, respectively.

In this embodiment, two voltage comparison circuits 10a and 10b are used.
When the potentials of the respective voltage monitoring points inputted to are both below the maximum allowable potential, both the first and second voltage comparison circuits 10a and 10b output "L" from their output terminals 19. Therefore, since "L" is input to both the first and second input terminals 2a and 2b of the detection circuit 20, "LJ" is also output from its output terminal 29.

On the other hand, in the first and second voltage comparison circuits 10a and fob, if at least one of the input voltage monitoring point potentials exceeds its maximum allowable potential, the voltage comparison circuit to which the abnormal voltage was input is rH from output end manual 9
Output. Further, the second voltage comparison circuits 10a, 10
All of the output terminals of b are connected to the input terminals of the detection circuit 20. Therefore, the first and second voltage comparison circuits 10a,
No matter which output terminal 19 of 10b outputs "H",
rH from the output terminal 29 of the detection circuit 20.

is output.

Therefore, in this embodiment, when monitoring the semiconductor device, it is usually sufficient to monitor only the output terminal 29 of the detection circuit 20. By detecting that the output changes from "L" to "H", it is possible to know whether the semiconductor device is abnormal.

In the voltage comparator circuit 10 of this embodiment, the comparator TC4 goes "H" when the potential input to the first input terminal 1a is lower than the potential input to the second input terminal 1b;
If it is high, it outputs "L", but this output is sent to the detection terminal 6.
It is possible to confirm at .

Therefore, in this embodiment, when an abnormality in the semiconductor device to be monitored is detected, the detection terminal 6 is set to Tli LE.
You can know the voltage monitoring point where abnormal voltage is input. That is, when rH is output from the output terminal 29 of the detection circuit 20, an abnormal voltage is input to the voltage comparison circuit having the detection terminal to which Lj is output.

Furthermore, the output to this detection terminal 6 is rHJ, "L"
Since this is carried out in a 2-bit signal, it is also possible to process this as a 2-bit signal and control the semiconductor device to be monitored based on the signal.

Description of other embodiments In the above embodiment, the semiconductor device has two voltage monitoring points, but if there are two or more voltage monitoring points, the number of voltage comparison circuits may be increased. It is possible to respond to inputs by

However, as the number of voltage comparison circuits increases, it is necessary to increase the pre-drying of the input terminal in the detection circuit. In this case, for example, if the above-mentioned detection circuit is used, the output can be increased to 1 by combining the detection circuits in a tournament manner.
It is possible to summarize and respond to the following. An example in this case is shown in FIG.

This embodiment is for a case where there are a large number of voltage monitoring points, and the number of voltage comparison circuits is increased in accordance with the number of voltage monitoring points. The respective output terminals of a large number of voltage comparison circuits are connected in a tournament manner in the aforementioned two-input detection circuit and combined into one output.

Also in this embodiment, when an abnormal voltage is input to at least one of all the voltage comparison circuits, a predetermined signal is output from the final output terminal.

Another way to deal with the increase in the number of voltage monitoring points is to
It is also possible to apply a multi-input OR circuit to the detection circuit.

Further, the voltage comparator circuit in the embodiment described above outputs an "H" signal when the potential at the voltage monitoring point exceeds its maximum allowable voltage.
This outputs the following. However, this means that if the potential at the voltage monitoring point falls below its minimum permissible voltage, r
It may be configured to output H. For this purpose, in the voltage comparator circuit, the potential of the voltage monitoring point may be input to the second input terminal, and the minimum allowable voltage thereof may be input to the first input terminal.

In the embodiments described above, the present invention is used for detecting abnormalities in semiconductor devices, but it can also be used for other purposes, such as fire detectors. For this purpose, in the voltage comparator circuit, the voltage from the terminal temperature sensor may be input to the first input terminal, and the voltage corresponding to the temperature at which the fire detector operates may be input to the second input terminal.

Although the present invention has been described above using examples, the present invention can be modified in various ways according to the gist of the present invention, and these are not excluded from the present invention.

[Effects of the Invention] As described above, according to the present invention, it is possible to easily monitor the potential of the voltage monitoring points regardless of the number of voltage monitoring points in the monitored device.

Therefore, it is possible to greatly simplify the effort involved in monitoring the monitored device, which greatly contributes to improving the performance of the related voltage monitoring device.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the basic principle of the present invention. FIG. 2 is a circuit diagram showing an example of a voltage comparison circuit in the present invention. FIG. 3 is a circuit diagram showing an example of a detection circuit in the present invention. FIG. 5 is an explanatory diagram showing another embodiment of the present invention. In the figure, la, 1b, 2a, 2b...input terminal, 19.29...output terminal, 3a...NC terminal, 3b...No terminal, 4...comparator IC. 5... Application terminal, 6... Detection terminal, 7... Relay 10... Voltage comparison circuit, 20... Detection circuit. A station side Q- 4 inverter IC
Figure 3 between the circuits showing the h1 arrow detection pruritus jE in the figure unknown

Claims (1)

[Claims] The first and second input terminals (1a, 1b) and the output terminal (1
9), and the potential of the voltage monitoring point input to the first input terminal (1a) exceeds the allowable potential in a steady state of the voltage monitoring point input to the second input terminal (1b). A plurality of voltage comparator circuits (10) generate a predetermined first signal from the output terminal (19).
) and a plurality of input terminals (2
) and one output terminal (29), and detects that the predetermined first signal is input to at least one of the plurality of input terminals (2), and outputs the output terminal ( 29) A voltage monitoring device comprising a detection circuit (20) that generates a predetermined second signal.