KR960000656Y1 - Ring signal detection circuit of telephone - Google Patents

Abstract

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Description

Ring signal detection circuit of telephone

1 is a ring signal detection circuit diagram of a conventional telephone.

2 is a ring signal detection circuit diagram of the present invention telephone.

3A to 3C are input / output waveform diagrams of respective parts of FIG.

(A) of FIG. 4 is a waveform diagram of an input ring signal, (b) is an output waveform diagram of FIG. 2, and (c) is an output waveform diagram of FIG.

* Explanation of symbols for main parts of the drawings

1 ring trimming part 3 rectifying part

2, 4: first and second medium width portions

The present invention relates to a ring signal sensing circuit of a telephone, and more particularly, to a ring signal sensing circuit of a telephone which enables a key system to accurately detect a ring signal coming from an exchange.

As shown in FIG. 1, the ring signal detecting circuit of the conventional telephone has a first ring signal detecting unit 10 which emits light by the ring signal flowing into the ring terminal and detects the ring signal, and a ring flowing into the tip terminal. It consists of a second signal detector 20 for emitting a light signal by the signal to detect a ring signal.

Referring to the operation of the ring signal sensing circuit of the conventional telephone configured as described above, the ring signal flowing into the ring is sequentially passed through the capacitor C1 and the resistor Rl. D1) is applied to the light emitting diode D1 to emit light. As the light emitting diode D1 emits light, the phototransistor Q1 is turned on to detect an input ring signal. In addition, the ring signal flowing into the tip terminal is condenser C2 and resistor R2. Are sequentially applied to the light emitting diodes D2 so that the light emitting diodes D2 emit light.

As the light emitting diode D2 emits light, the phototransistor Q2 is turned on to detect an input ring signal. However, the ring signal sensing circuit of such a conventional telephone has a low resistance value in order to operate the optical coupling element, which causes a decrease in signal sensitivity during a call, and the sensing signal outputs a 'high' signal for one ring signal. Since the signal is converted to 'low', the amount of software processing of the CPU increases.

Accordingly, an object of the present invention is to provide a ring signal detection circuit of a telephone that allows a key system to accurately detect a ring signal coming from an exchange.

An object of the present invention as described above is a ring ring means for trimming and outputting the input ring signal, the first amplifying means for inverting and outputting the signal output from the ring trimming means, and the output from the first amplifying means This invention is achieved by configuring a rectifying unit 3 for rectifying the signal and a second amplifying means for amplifying the output level by amplifying the signal output from the rectifying unit 3 to a predetermined level. Permanent reference is as follows.

2 is a ring signal sensing circuit of the present invention, as shown in FIG. 2, a resistor R1 to R8 for outputting a trimmed signal by trimming a signal flowing into a ring and a tip terminal (Tip), and variable Trimming section 1 composed of resistors LV1 Zenerdio (Dl) D2, resistors R9 to R1 for inverting and amplifying the signals output from the ring trimming section 1, and capacitors C3 and C4. ) And a rectifier (3) consisting of an amplifier (A2), resistors (R16 to R25), capacitors (C5), and amplifiers for amplifying the output level appropriately by amplifying the signal output from the step (3) to a predetermined level. It consists of the 2nd amplifier part 4 comprised by (A3, A4).

With reference to FIGS. 3 to 5 attached to the operation and effects of the present invention configured as described above, a 50HZ ring signal is input across the capacitors C1 and C2 through the ring and the tip terminal (Tip). When the input ring signal is combined into a single signal through the resistors Rl and R2, the signal is converted into a ring signal of a predetermined level while passing through the resistors R3 to R5 and the variable resistors V1 and 1 And zener diodes D1 and D2.

The ring signal applied to the Zener diodes D1 and D2 is trimmed by the Zener diodes D1 and D2 as shown in FIG. 3B, so that the first amplifier A1 of the first amplifier 2 is applied. ) To prevent overvoltage input.

The trimmed signal is inverted and amplified through the first amplifier A1 of the first amplifier 2 and input to the inverting terminal (-) of the second amplifier A2 of the rectifier 3 and then diode D3. Full-wave rectified via (D4).

That is, since the positive signal of the output of the first amplifier Al of the first amplifier 2 turns on the diode D3, it is full-wave rectified through the diode D3 and then the second amplifier 4 The negative signal (-) of the output signal is applied to the inverting terminal (-) of the third amplifier (A3) of < RTI ID = 0.0 > (3) < / RTI > The inverting terminal of (-) is input.

The rectified signal at this time is as shown in FIG.

The signal input to the third amplifier A3 of the second amplifier 4 is amplified to a predetermined level through the third amplifier A3, and then becomes a 'low' signal to form the second amplifier 4. The fourth amplifier A4 of the fourth amplifier A4 is input to the non-inverting terminal (+) of the amplifier A4, and thus the fourth amplifier A4 of the second amplifier 4 amplifies the signal output from the third amplifier A3 to a predetermined level. The 50HZ ring signal is detected by outputting a 'low' signal.

As described in detail above, the present invention allows the resistance of both ends of the tip and ring terminals to be sufficiently increased by providing an amplifier in the ring sensing internal circuit so that the ring signal level loss of the switching station is almost eliminated, and the ring sensing signal has only two signals. The signal 'low' signal is maintained when there is a ring, and the 'high' signal is maintained when there is no ring signal, thereby reducing the software processing for the CPU to detect the ring.

Claims (4)

Ring ring means for trimming and outputting an input ring signal, first amplifying means for half-amplifying and outputting the signal output from the ring trimming means, and rectifier means for rectifying the signal output from the first amplifying means; And second amplifying means for amplifying the output level by amplifying the signal output from the rectifying means to a predetermined level. 2. The trimming means according to claim 1, wherein the trimming means comprises a capacitor (C1, C2) and resistors (R1 to R5) for changing the input ring signal to a predetermined level, and the capacitors (Cl, C2) and resistors (R1 to R5). A ring signal sensing circuit of a telephone, characterized in that it comprises a Zener diode (Dl, D2) and a variable resistor (VL, 1) for trimming the signal output through the signal. 2. The apparatus of claim 1, wherein the rectifying means comprises: a first diode for rectifying the signal output from the first amplifying means, an amplifier for inverting and amplifying the signal output from the first amplifying means, and an output from the amplifier. A ring signal sensing circuit of a telephone comprising a rectifying second diode. The method of claim 1, wherein the second amplifying means comprises: a first amplifier for amplifying and outputting a signal through the first diode and the second diode of the rectifying means to a predetermined level, and a signal output from the first amplifier; And a second amplifier for amplifying and outputting at a level of the ring signal sensing circuit of the telephone.