Patent
Subscriber line circuit for connection of a subscriber line for the transmission of analogue subscriber signals to a digital time division multiplex telephone exchange
TLDR
In this paper, a programmable filter (Z, B) which connects the four-wire transmit branch to the fourwire receive branch in a chip (SICOFI) connected together with the interface circuit (SLIC1) and also ensures that the two-wire impedance is provided with a complex value is provided.Abstract:
The subscriber line is coupled capacitively (C, K). In the subscriber line interface circuit (SLIC) of the line circuit, a positive feedback path leading from the four-wire transmit output to the four-wire receive input and containing filter elements (F) is formed, by means of which a basic setting of the two-wire impedance is effected which is higher than the impedance of the feed bridge, this basic setting is complemented to form the required exact value with the aid of a programmable filter (Z, B) which connects the four-wire transmit branch to the four-wire receive branch in a chip (SICOFI) connected together with the interface circuit (SLIC1) and also ensures that the two-wire impedance is provided with a complex value.read more
Citations
More filters
Patent
Subscriber line interface circuit with impedance synthesis
TL;DR: In this article, the authors proposed a battery feed circuit (10) with a simple resistive feed (LFR1, LFR51) to provide DC current to the load.
Patent
Circuit arrangement for transmitting signals in telecommunications networks
Jörg Hauptmann,Alexander Kahl +1 more
TL;DR: In this paper, the authors proposed a circuit arrangement for transmitting signals in telecommunications networks, which has a first connection and a second connection for a first or a second lead of a transmission line.
Patent
Circuit arrangement for forming the termination of an analogous subscriber line
Hauptmann Joerg,Alexander Kahl +1 more
TL;DR: In this paper, the termination of an analogous subscriber line with a twin-wire analogous line is discussed. But the circuit arrangement is different from the one described in this paper, in that a direct current source is linked with the first point of linkage of the first capacitor and the first adjustable resistor.
Patent
Circuit arrangement for signaling in telecommunications networks
Alexander Kahl,Jörg Hauptmann +1 more
TL;DR: In this paper, the first connection is connected to the first input of a rectifier, and the second connection to the second input of said rectifier are connected to one another via a variable resistance.
References
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Patent
Fault protection for integrated subscriber line interface circuits
TL;DR: In this article, an integrated SLIC having input pins coupled to the wires of a two-wire telephone subscriber line is protected from excessive voltages on the line by reverse biassed 60 volt zener diodes connected between each input pin and ground, normally reverse-biassed diode within the integrated circuit connected between the input pin, and a normally forward biassed diode connected between substrate and a -48 volt (nominal) supply voltage.
Patent
Pcm coder/decoder with two-wire/four-wire conversion
TL;DR: In this article, an analogue balancing circuit (13) is provided between the output terminal of a post-filter and the input terminal of the pre-filter in order to effectively eliminate a return signal in the case of two-wire/four-wire conversion.
Patent
Circuit arrangement for an electronic interface circuit
TL;DR: In this article, the interface circuit is disconnected both from the wires of the subscriber line and from the feed voltage of the UB, in the case of partial disconnection, the part still supplied with voltage contains the indication circuit and with complete disconnection a separate indication circuit (K) is connected to be active.