KR0152368B1 - Analog hybrid integrated circuit for telephone line connection - Google Patents

Abstract

The present invention provides an integrated circuit constituting a switchboard subscriber board. In particular, in order to prevent specific degradation caused by interference between signals, the analog and digital parts are separated and hybridized. In the related art, in the related art, the GSLA part, which is the subscriber part matching device of the exchange, is hybridized by combining two parts of SLIC and SLAC, but the analog part (SLIC) and the digital part (SLAC) are hybridized into one. The electrical characteristics are deteriorated, and when the SLIC is fixed, the SLAC is changed at the same time, so there is a problem in that it is economically expensive. The present invention separates the analog and digital parts and hybridizes them respectively, so that the characteristics due to mutual signal interference Is prevented from being lowered and the board for subscriber matching device In the repair by replacing the analog section, causing the main fixed, will help you to reduce the loss of parts.

Description

Analog Hybrid Integrated Circuits for Telephone Line Connections

1 is a circuit diagram illustrating an analog hybrid integrated circuit for telephone line connection according to an embodiment of the present invention.

2 is a block diagram illustrating a part of an AM7950KJC IC chip in an analog hybrid integrated circuit for telephone line connection according to an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

100: current limiting unit 200: relay drive unit

300: ring circuit portion

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated circuit constituting a switchboard subscriber board. In particular, a telephone line connection comprising a hybridization of analog parts by separating analog parts and digital parts to prevent deterioration of characteristics due to interference of mutual signals. It relates to an analog hybrid integrated circuit for.

Generally, GSLA (Analog Subscriber Line Interface PBA Assembly), which is a subscriber part matching device of a switch, is a hybridization of a circuit of a part connected to a telephone line, and is applied to a local exchange, a private switch, a mobile communication switch, and a cable television subscriber matching device. Used.

Conventionally, this part was used by hybridizing two parts of a subscriber line interface circuit (SLIC) and a subscriber line audio processing circuit (SLAC).

However, in this case, the analog part (SLIC) and the digital part (SLAC) are hybridized into one, so the electrical characteristics are deteriorated, and the purpose of the hybridization is to ensure the ease of replacement in case of failure. The cause is due to the SLIC failure, which is an analog part, and the conventional hybrid has been economically lost because it is required to simultaneously change the SLAC due to the failure of the SLIC.

The present invention is to solve such a problem of the prior art, in particular, by separating the analog portion from the digital portion and hybridization, thereby preventing the degradation of the characteristics due to interference of the mutual signal, and also in the maintenance of the board for subscriber matching devices Therefore, by replacing only the analog parts that cause the main fixing, it is possible to reduce the loss of parts.

In other words, by placing the RSN pin peripheral parts as close as possible, the analog sound quality is improved, and the RING / IN pin is a part that takes more than about 90V voltage, and when the digital part is together, the electrical characteristic is reduced by the RING signal. In the present invention, the digital part not shown is hybridized separately and separated from the analog part, thereby improving characteristics.

Hereinafter, described in detail with reference to the drawings.

1 is an embodiment of the present invention, in which the pin arrangement is designed in consideration of the electrical characteristics, in the present invention of the arranged pins, only important pin numbers are described, and the rest are general descriptions are omitted.

In FIG. 1, the current limiter 100 is composed of R1, R2, R3, R4, C4, and C5. The AM7950KJC IC (manufacturer AMD: ADVANCED MICRO CEVICE) provides power to the phone, relay operation, and impedance matching. In order to handle the charge according to the talk time of the public telephone rather than the telephone of the general home or office, the current is applied to the RDC that reverses the polarity and the RSN that amplifies the current and removes noise at the same time, and the relay driver 200 Comprised of a transistor (Q1) and a resistor (R7) to amplify the relay drive current to check the state of the subscriber line to drive the relay, the ring circuit unit 300 so that the current can be applied to the relay driver 200 The present embodiment is constituted by forming a closed loop.

First, RSN (Receive Summing Node), pin 1, is designed to gain 1000 as the current amplification part, so it is very sensitive to noise because of the large gain, so that the digital part is separated to prevent it, and the digital part is located where it is located. The current limiting part 100 consisting of R1, R2, R3, R4, C4, and C5 is disposed closest to the pin to ground the component surface of the hybrid IC substrate having the component, and the signal line is in the opposite direction to the component surface. Processing minimizes the effects of noise.

In addition, the current supplied from the telephone line is restricted so that a certain amount does not flow in the RDC and RSN of the AM7950KJC, and the ring circuit unit 300 consisting of R9, R10, R11, R12, R13, and C12 is connected to pins 13, 16, and 17. When the appropriate logic signal is applied, the SLIC is in a ring state and pin 6 is grounded to form a closed loop for driving a relay (not shown), and the relay driver 200 including the transistor Q1 and the resistor R7 is provided. To form a closed loop capable of driving a relay in the ring circuit unit 200 to check the state of the subscriber line, amplifies the current input from pin 8 to drive the relay.

As shown in FIG. 2, a part of the AM7950KJC IC chip is used to calculate the resistance value and the capacitance value of each device using a current limiting diode.

Also, if current limiting diode 1N4148 is used for current limiting, the current flowing to RSN pin

Becomes

Here, when the line resistance is 600 ohm, which is our standard value, the DC feed resistance is 20 ohm and the maximum current is 50 mA,

Becomes

In order to find the value of C4, if the polarity inversion time is 1.0ms,

Time constant T = C4 * Rt Rt = Parallel composite resistance of R1 and R2

Therefore, the value of C4 in the above equation (3) is 0.22μF.

As described above, the present invention improves the electrical characteristics by miniaturizing the hybrid IC and separating the RSN pin (1) and the ring / IN (6) peripheral circuits from the digital parts, thereby improving the maintenance of the board for the subscriber matching device. Therefore, the loss of parts can be reduced by replacing only the analog parts that cause major failures.

Claims (1)

Hybrid integrated circuit for telephone line connection, consisting of R1, R2, R3, R4, C4 and C5, two polarization inversion and current amplification of integrated circuit that supplies power to telephone, relay drive and impedance matching A current limiting unit for limiting a current applied to each pin and removing noise at the same time; A relay driver comprising a transistor Q1 and a resistor R7 for driving the relay by amplifying the relay driving current to check the state of the pressurized magnetic path; And a ring circuit for forming a closed loop to allow a current to be applied to the relay driver.