DD138401B1 - IDENTIFICATION MARKET WITH SERIAL SWITCHING OF POWER SOURCES AND SWITCHES - Google Patents

Description

For this 1 page drawing

Field of application of the invention

The invention relates to license plate converter with a series circuit of power sources and switches for the adaptation of transmission equipment to switching equipment, the license plate converter converts all necessary for the establishment of a telephone connection switching characteristics in signals that can be processed and transmitted by the transmission facilities and vice versa.

Characteristic of known technical solutions

The increasing use of digital transmission technology in telephone technology also requires the conversion of switching characteristics of the switching technology into digital signals. This is especially true for PCM transmitters where tag converters are used to adapt the switch tags to the digital transmission link

become.

Known tokens converters incorporate resistors with transistors as switches or relays or current sources to mimic a portion of the switching technique. These components and assemblies are necessary in order to create negative, earth potential or insulation on the connecting wires to the upstream or downstream switching device so that the individual switching devices are stimulated, adjusted and monitored via this switching indicator

can.

Is the switching technology from Hebdreh- or similar voters, so is a DC connection of

I. Group voter (I. GW) or I. group connector (I. GV) to the line selector (LW) or subscriber connector (TV) available. The wire resistance between these devices can be from about 0 ohms to about 1, 000 ohms, depending on which one dials which one.

For a transmission device lying in such a connection with the indicator converters necessary for the adaptation, two states occur in the extreme case:

1. The wire resistances between the switching devices to be adjusted are approximately 0 ohms, because the entire connection line is replaced by the transmission device.

2. The wire states are around the maximum possible values, because only a short piece of the connection line is replaced by the transmission device.

The tag converters must therefore adapt to the switching devices with a wire resistance range of about 0 ohms to about 1 500 ohms by itself or even with the largest wire resistance enough current must flow so that the relay of the switching technology respond.

For license plate converter with ohmic resistors and switches (relay contacts or transistors) means that in relay resistors of 500 to 1000 ohms, wire resistance of about 1 500 ohms and a necessary minimum current of about 2OmA at a DC operating voltage of 60V, the ohmic resistance is on the order of 500 to 1000 ohms. If negative potential is now output to the switching technology via this ohmic resistor, the power loss to be absorbed by the resistor must be calculated for the fault "ground fault of the connecting wire" and a corresponding resistance is used Resistors for approximately 7 W losses are spatially very large and disturbing in electronic circuits.

Likewise, the high difference between the power loss in normal operation, z. B. about 0.6 W at 750 ohms per connection wire and each 750 ohms real resistance, i. 2250 ohms total resistance and 7 W at ground fault of the connecting wire unsatisfactory.

In order to eliminate this great disadvantage, current sources instead of resistors and switches in the license plate converter at about 2OmA necessary power and a DC operating voltage of 60V at about 1.2W instead of about 7W were switched. Thus, the power loss occurring is indeed significantly reduced, but the size of the transistor and the associated heat sink, which is usually necessary because of the size of the power loss, but could not be reduced because transistors can only reach a maximum of 100 ° C on the housing up to 140 ⁰ C and for wire wound resistors surface temperatures of 300 ⁰ C to 400 ⁰ C are allowed. The space requirement of the circuit arrangement is still large, especially since a considerable space requirement is claimed due to the number of license plate converter blocks in a PCM transmission device.

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Object of the invention

The object of the invention is to provide a license plate converter, which is both in terms of loss power and Flächenbzw. Volume requirement is minimized.

Explanation of the essence of the invention

The object of the invention is an arrangement for license plate converter of the PCM transmission technology, which is suitable to exploit the power loss multiple times to reduce the power loss.

According to the invention this object is achieved in that the circuit arrangement for the license plate converter consists of a combination of current sources and transistor switches, which are connected in series. This ensures that the power sources can be exploited several times, since in most of the used indicator systems of the switching equipment in the most important cases the same potentials simultaneously applied to the connecting wire a and b. With a circuit that has two power sources - one is for the potential minus and the other for the potential. Earth provided - and contains four transistor switches, the following conditions are possible:

State Connecting wire a Verbindungsaderb 1 minus earth 2 earth minus 3 isolation isolation 4 minus isolation 5 earth isolation 6 isolation minus 7 isolation earth

Detection circuits can be arranged in parallel via the emitter resistors of the current sources, which by means of a binary signal at their outputs allow the conclusion as to whether current flows. ,

embodiment

The invention will be explained in more detail below using an exemplary embodiment.

FIG. 1 shows a circuit arrangement with two current sources and four transistor switches. The first current source consists of the pnp transistor T1 with the base voltage divider of resistor R1 between the base of transistor T1 and negative operating DC voltage Ub and resistor R 2 between the base of transistor T1 and ground potential and an emitter resistor R3 between the emitter of transistor TI and ground potential.

Parallel to the emitter resistor R3, the detection circuit A is arranged, which is coupled to a control logic. The collector terminal of transistor TI is connected to the emitter terminals of the two subsequently arranged pnp switching transistors T3 and T6. The collector of the pnp switching transistor T3 is in turn connected to the telecommunication connection wire a and the collector of the pnp switching transistor T6 to the telecommunication connection wire b. The base of the pnp switching transistors T3 and T6 is coupled to the control logic.

The second current source is composed of the NPN transistor T2 to the base voltage divider of resistor R4 between base vonTransistorT2und potential earth, and resistor R5 between the base of transistor T2 and negative DC operating voltage Ub and an emitter resistor R6 between the emitter of transistor T2 and negative DC operating voltage U. ₈ Parallel to the emitter resistor R 6, the detection circuit B is arranged, which is also coupled to the control logic. The Kolle'ktoranschluß of transistor T2 is connected to the emitter terminals of the two subsequently arranged npn switching transistors T4 and T5.

The collector of the npn switching transistor T4 is in turn connected to the telecommunication connection wire a and the collector of the npn switching transistor T5 to the telecommunication connection wire b.

The base of the npn switching transistors T4, T5 is also coupled to the control logic.

The control loop, the external control commands and the states at the outputs of the detection circuits A, B processes, locks or controls the transistor switches T3, T4, T5, T6 in accordance with the requirements of the switching technology.

Claims (1)

Invention claim: License plate converter with a series connection of current sources and transistor switches for the adaptation of transmission equipment to switching equipment, wherein the license plate converter converts all necessary for establishing a telephone connection switching characteristics into signals that can be processed and transmitted by the transmission facilities and vice versa, characterized in that a first Current source (T1), which is to apply ground potential to the telecommunications connection wires, with the emitter terminal of two pnp switching transistors (T3, T6) is connected and the first pnp switching transistor (T3) via its collector, the ground potential to the connecting wire a and the second pnp Switching transistor (T6) connects to the connecting wire b and a second current source (T2), which is to apply negative potential to the telecommunications connection wires, with the emitter terminal of two npn switching transistors (T4, T5) is connected and the np n switching transistor (T4) via its collector, the negative potential to the connecting wire a and the second npn switching transistor (T5) to the connecting wire b and in parallel across the emitter resistors (R 3, R 6) of the transistors (T1, T2) both current source detection circuits (A), (B) are arranged, which are coupled to a control logic.