KR100191217B1 - Circuit and method for volume control in a telephone - Google Patents

Abstract

On the phone, the user selects the ring volume through the key input section and adjusts the ring volume by the program. To this end, when key data for ring volume control is generated through the input unit, first and second control signals for ring volume control are generated by the key data. The ring volume control circuit has a configuration in which a resistor and a first switch are connected in parallel between a reception ring signal and a speaker, and a second switch is connected between the reception ring signal and a ground. Therefore, the first and second switches are switched according to the state of the first and second control signals to adjust the ring volume.

Description

Ring Volume Control Circuit and Method of Telephone

1 is a ring volume control circuit of a conventional telephone.

2 is a ring volume control circuit diagram of a telephone according to the present invention.

3 is a flowchart of ring volume control of a telephone in a ring standby state.

4 is a flowchart of ring volume control of the telephone in the ring arrival state.

* Explanation of symbols for main parts of the drawings

201: key input unit 202: central processing unit

203: bridge circuit 204: ringer circuit

205 ring detection circuit 206 transformer

207: volume control circuit 208: speaker

The present invention relates to a ring volume control device and method for a telephone.

In general, a mechanical switch of the configuration shown in FIG. 1 is used to adjust a ring volume in a telephone. Referring to the conventional ring volume control method according to FIG. 1, a ring signal applied to both ends of the tip and the ring is generated in the ringer circuit 102 through the bridge circuit 101, and such a ringer circuit. The output of the 102 is generated as an audible sound in the speaker 104 through the transformer 103 at the volume level set by the three-stage switch SW. The three-stage switch (SW) is a mechanical switch attached to the front of the phone, the user operates the three-stage switch (SW) to position the CT1-CT3 terminal. In this case, when the three-stage switch SW is located at the CT1 terminal, the ring sound is not generated by bypassing to the ground terminal. When the three-stage switch SW is located at the CT2 terminal, the low tone is applied to the speaker 104 through the resistor R. When the ring volume is adjusted and positioned at the CT3 terminal, the received ring signal is applied to the speaker 104 as it is, so that the ring tone is generated at a high tone.

However, the ring volume control method as described above is not beautiful in appearance because it uses a mechanical three-stage switch, and the switch part is vulnerable due to external electric shock (ESD, etc.), and the switch is located at the front of the transformer so that it depends on the PCB mounting position. It can affect other signals.

Accordingly, an object of the present invention is to provide an apparatus and method for removing an external switch for adjusting the ring volume by controlling the ring volume using an electronic switch in a telephone.

Hereinafter, the present invention will be described in detail with reference to the drawings.

2 is a block diagram of a ring volume control apparatus for a telephone according to the present invention. The key input unit 201 has a structure having an arrangement of numeric keys and function keys, and generates a key signal for ring volume adjustment by a user. At the same time, it generates dialing and function key signals. The central processing unit 202 outputs first and second control signals for ring volume adjustment according to the output key signal of the key input unit 202.

The bridge circuit 203 is connected to a telephone line to perform a rectifying function. The ringer circuit 204 is connected to the bridge circuit 203 to detect a ring signal received.

The ring sensing circuit 204 is connected to the ringer circuit 204 to output a ring sensing signal to the central processing unit 202 when detecting a ring. The transformer 206 is connected to the ringer circuit 204 to match the impedance of the received ring signal.

The volume control circuit 207 connects the resistor 211 and the first switch 212 in parallel between the first node N1 and the second node N2, and the second switch 213 between the first node N1 and the ground terminal. Connect it. In this case, the first node N1 is connected to the output terminal of the transformer 206 and the second node N2 is connected to the speaker 208. The volume control circuit 207 is the first switch 212 is turned on when the central processing unit 202 outputs the first control signal to output a high level ring signal, the second switch when the second control signal output 213 is turned on to mute the ring signal by bypassing the receive ring signal to the ground terminal, and the first and second switches 212 and 213 are turned off when the first and second control signals are not generated. A low level ring signal is generated through 211.

3 illustrates a process of adjusting the ring volume in the ring standby state.

4 shows the process of adjusting the ring volume in the ring arrival state.

Based on the above-described configuration of FIG. 2, the present invention will be described in detail with reference to the flowcharts of FIG. 3 and FIG.

First, when there is no AC power, since the central processing unit 202 and the peripheral devices are not supplied with power, the first switch 212 and the second switch 213 are turned off, so that the ring signal is transmitted only through the resistor 211. Therefore, the speaker 208 generates ring sounds only at a predetermined volume level. However, when AC power is supplied, the central processing unit 202 controls the generation of ring sounds at the volume level set by the key input unit 202.

That is, when a ring signal is received from the telephone line, the ringer circuit 204 detects the received ring signal, and the transformer 206 controls the impedance so as to reproduce the received ring signal through the speaker 208. Adjust the volume of the ring signal according to the condition.

First, the process of adjusting the ring volume in the ring standby state will be described with reference to FIG. The ring standby state refers to an on-hook state, and when the ring volume is to be adjusted in the above state, the user may continuously generate a registration key → volume selection key → registration key through the key input unit 201. In this case, it is assumed that the * key is turned off and the low volume # key selects the high volume as the volume selection key. Therefore, the CPU 202 checks whether the registration key → volume selection key → registration key is continuously received through steps 301 to 303. At this time, if the key is continuously received in the same procedure as described above, the CPU 202 performs the steps (304-310) to control the switches (212, 213) of the volume control circuit 207 to the selected volume level. That is, when the * key is received, it is determined as an off function in step 304 and the first control signal is turned off in step 305 and the second control signal is turned on. Then, since the ring signal received when the second switch 213 is turned on is bypassed to the ground terminal, the ring signal is not applied to the speaker 208 to perform a mute function. In addition, when the 0 key is received, it is determined as a low volume in step 306, and the first control signal and the second control signal is turned off in step 307. Then, since the first switch 212 and the second switch 213 are turned off, the ring signal received through the resistor 211 is applied to the speaker 208, so that the ring volume is adjusted to a low volume level. When the # key is received, it is determined as a high volume in step 308, and turns on the first control signal and turns off the second control signal in step 309. Then, since the first switch 212 is turned on and the second switch 213 is turned off, the received ring signal is applied to the speaker 208 as it is.

In the above, the first switch 212 and the second switch 213 may use an element such as a transistor. In addition, the size of the ring volume may be determined according to a specification. In the present invention, the ring volume is set to 65 dBSPL at a high level and the ring volume is set to 55 dBSPL at a high level.

Then, the resistor 211 may use 12 kV.

In addition, the ring volume can be adjusted in the same manner as in FIG. In the ring arrival state, when a ring signal is received in an on-hook state, when a ring signal is received, the ring detection circuit 205 is sent to the CPU 202 by a ring signal detected by the ringer circuit 205. Output a ring detection signal. Then, the central processing unit 202 detects the reception of the ring signal in step 401, and when the key input unit 201 generates key data, the key processing unit 202 receives the key data in step 402.

Thereafter, steps 403-409 are performed to control the switches 212 and 213 to the corresponding volume if the received key data is a key for volume control.

As described above, the volume control switch that protrudes to the outside can be removed by selecting the size of the ring volume in the phone as a program, thereby improving workability in PCB design and reducing costs.

Claims (2)

An apparatus for adjusting a ring volume of a telephone, comprising: an input unit for generating key data for adjusting a ring volume, means for receiving the key data and generating first and second control signals for adjusting the ring volume; A first node connected to the second node, a second node connected to the speaker, a resistor connected between the first node and the second node to form a path of a low volume signal, and between the first node and the second node. A first switch connected in parallel with a resistor and switched by the first control signal to form a path of a high ring volume signal, and connected between the first node and a ground terminal, and switched by the second control signal. Ring volume adjusting device of the telephone, characterized in that consisting of a second switch to form a mute passage of the ring signal. A ring volume adjusting method of a telephone in which attenuating elements and a first switch are connected in parallel between a ring receiving terminal and a speaker, and a second switch is connected between the ring receiving terminal and a ground terminal, wherein the key data is received in an on-hook state. During the test volume selection key application, during the checking process, switching the second switch to mute the received ring signal, and when receiving the low key data during the checking process, the first and second Controlling a switch to attenuate a reception ring signal through the attenuation element, and switching the first switch when receiving high-key data during the inspection process and applying a reception ring signal to the speaker without attenuation. How to adjust the ring volume of the telephone.