JPH03245647A - Electronic exchange - Google Patents

Abstract

PURPOSE:To avoid a driver IC at an output terminal of a line adaptor section from being destroyed at maintenance by providing a interrupter interrupting a control signal line forcibly at its drawing end in response to power interruption in a said line unit to the control signal line drawing end in each line unit. CONSTITUTION:An interrupter 8 interrupting a control signal line 4 forcibly at its drawing end in response to power interruption in a said line unit 6 is provided to the control signal line drawing end in each line unit 6. Thus, the control signal line 4 is used in common by plural line units 6, 6... to improve the degree of freedom of the constitution of an exchange. While the interrupter 8 is opened when a said power supply circuit 5 is turned off and the control signal line 4 is interrupted from an output terminal of line adaptors 1, 1... at the drawing end of the said line unit 6. Thus, even when the line adaptors 1,1... are replaced in this state for the purpose of maintenance or the like, no damage is given to a built-in driver IC or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an electronic exchange that allows lines to be added in units of a certain number of units.

(Prior Art) FIG. 2 is a block diagram showing the overall configuration of a conventional electronic exchange, and FIG. 3 is a block diagram showing the configuration of each line.

As is clear from these figures, in conventional electronic exchanges of this type, a plurality of line support units 1, which function as interfaces with terminals or external networks, are mounted together in a common rack with a built-in power supply, and the line units 6 are A plurality of line units 6 configured in the same manner are connected to the central control unit 2 via a common control signal line 4, and the control signal line 4 is commonly connected to the line corresponding unit 1 in each line unit 6. At the same time, it is pulled up to the power supply circuit 5 in the line unit 6 via the pull-up resistor 7, and transmission of dial information etc. is carried out via the control/signal line 4 between each line corresponding section 1 and the central control section 2. It is supposed to be done.

In FIG. 2, reference numeral 3 denotes a time switch unit for switching and connecting communication paths according to instructions from the central control unit 2.

According to such a configuration, since the power supply circuit 5 is built into each line unit 6, by connecting the necessary number of these line units, it is possible to add lines in units of a certain number. can.

However, in such a conventional electronic exchange, the output end driver IC of the line corresponding parts 1, 1, . It is also pulled up by the power supply circuit 5.

Therefore, even if the power to one of the line units 6 is cut off for maintenance or the like, the output end driver IC of the line corresponding section 1 in the line unit 6 concerned will be affected by the loop from the power supply circuit 5 in the other line unit 6. This means that power is being applied.

At this time, power is not being supplied to the driver IC in the line unit 6, so if the line corresponding circuit 1 is replaced for maintenance etc. in this state, excessive stress will be placed on the built-in driver IC. There is an inconvenience that the repetition of this process will eventually lead to destruction of the driver IC.

(Problems to be Solved by the Invention) As described above, in the conventional electronic exchange, the output end driver ICs of the line corresponding parts 1, 1, . Since it is also pulled up by the power supply circuit 5 in other line units 6, even if the power to any line unit 6 is cut off for maintenance etc., the output terminal of the line corresponding part 1 in the line unit 6 concerned will be pulled up. Power is being applied to the driver IC by looping from the power supply circuit 5 in another line unit 6, and at this time, power is not being supplied to the driver IC in the line unit 6.
If the line-corresponding circuit 1 is replaced for maintenance or the like in such a state, excessive stress is applied to the built-in driver IC, and repetition of this process eventually leads to destruction of the driver IC.

Therefore, in order to avoid such damage to the driver IC during maintenance, it is necessary to limit the range supported by one control signal line 4 to one line unit 6, which imposes restrictions on the configuration method of the exchange. That was the result.

This invention was made in view of the above problems,
The purpose of this is to prevent the output end driver IC of the line handling section from being destroyed during maintenance, and thereby provide an electronic exchange that allows one control signal line to be shared by multiple ports. be.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention has a plurality of line compatible units that function as terminals or interfaces with external networks, are mounted together in a common rack with a built-in power supply, and each line is connected individually. A plurality of line units configured in the same manner are connected to the central control unit via a common control signal line, and the control signal line is commonly connected to the line corresponding unit within each line unit, and the line units within the line unit are In an electronic exchange in which dial information, etc. is transmitted via a control signal line between each line corresponding section and the central S section, the control signal line in each line unit is pulled up to the power supply of the The device is characterized in that a circuit breaker is provided at the end of the control signal line for forcibly cutting off the control signal line at its lead-in end in response to a power cut in the line unit.

(Function) According to such a configuration, the control signal line can be shared by multiple lines at all times, but during maintenance, when the power is turned off, power is not applied to the output end of the line corresponding part within the line unit. Therefore, even if the line corresponding part is replaced in this state, stress will not be applied to the driver IC.

(Embodiment) FIG. 1 is a block diagram showing an embodiment of an electronic exchange according to the present invention.

In this figure, the same reference numerals are given to the same components as those of the conventional example shown in FIG. 3, and the explanation thereof will be omitted.

The switch of this embodiment is characterized by a circuit breaker installed at the control signal line lead-in end of each line unit 6, which forcibly interrupts the control signal line 4 at the lead-in end in response to a power cut in the line unit 6. In the illustrated example, an optically coupled MOS relay (8) is provided.

That is, when the power supply circuit 5 is powered on, the circuit breaker 8 conducts and connects the control signal line 4 to each line corresponding section 1, 1.
Connect to the output end of...

Therefore, one control signal line 4 can be connected to multiple line units 6.6
... can be shared, improving flexibility in the configuration of the exchange.

On the other hand, the circuit breaker 8 becomes non-conductive when the power supply circuit 5 is powered off, and the control signal line 4 is connected to the output terminal of each line corresponding section 1.1 at the lead-in section of the line unit 6. be isolated from

Therefore, even if the line corresponding parts 1, 1, etc. are replaced for maintenance etc. in this state, the built-in driver IC
etc. will not cause any damage.

Furthermore, in this embodiment in particular, since an optically coupled MOS relay is used as the circuit breaker 8 instead of a contact relay, the possibility of disturbance occurring on the control signal line 4 can be avoided.

〔Effect of the invention〕

As is clear from the above embodiments, according to the present invention,
While the control signal line can normally be shared by multiple lines,
During maintenance, when the power is turned off, power is no longer applied to the output end of the line corresponding part in the line unit, so even if the line corresponding part is replaced in this state, stress will not be applied to the driver IC.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of an electronic exchange according to the present invention, FIG. 2 is a block diagram showing the overall configuration of a conventional electronic exchange, and FIG. 3 is a block diagram showing the configuration of each line. . DESCRIPTION OF SYMBOLS 1... Line correspondence part, 2... Central control part, 3/10 hour switch, 4... Control signal line, 5... Power supply circuit,
6... Line support section, 7... Pull-up resistor, 8...
- Breaker.

Claims (1)

[Claims] (1) Multiple line units that function as interfaces with terminals or external networks are mounted together on a common rack with a built-in power supply to configure a line unit, and multiple line units configured in the same way are connected to a common control signal line. connected to the central control unit via
and commonly connects the control signal line to the line corresponding part in each line unit and pulls it up to the power supply in the line unit,
In an electronic exchange in which dial information, etc. is transmitted between each line corresponding section and a central control section via a control signal line, a control signal line lead-in end within each line unit is provided with a An electronic exchange characterized by being provided with a circuit breaker that forcibly interrupts a control signal line at its lead-in end in response to a power cut.