KR20070074952A - Mobile communication terminal and method for optimizing speaker character thereof - Google Patents

Abstract

A mobile communication terminal and a speaker property optimization method thereof are provided to control gain margins within a range for ensuring sound quality and maximum input power by sensing a frequency and a current of a speaker input port of the terminal, thereby guaranteeing optimum performance as preventing damage. A sound source data DB stores sound source data. A controller(100) amplifies and processes the sound source data according to predetermined gain margins. An audio amplifier(200) amplifies the sound source data outputted from the controller, and outputs the amplified data to a speaker(400). A speaker property compensator(300) senses a frequency and an input current of the speaker, and outputs a gain margin control signal for controlling the gain margins to compensate properties of the speaker.

Description

MOBILE COMMUNICATION TERMINAL AND METHOD FOR OPTIMIZING SPEAKER CHARACTER THEREOF}

1 is a graph illustrating a problem of a general speaker.

2 is a schematic structural diagram of a mobile communication terminal according to an embodiment of the present invention;

3 is a waveform diagram comparing and comparing the speaker characteristic curve and the ideal characteristic curve of the mobile communication terminal of FIG.

4 is a flowchart illustrating a speaker optimization method of the mobile communication terminal of FIG. 2.

FIG. 5 is a flowchart specifically illustrating a process of compensating speaker characteristics using the compensation signal of FIG. 4. FIG.

*** Explanation of symbols for the main parts of the drawing ***

100: control unit 110: sound source data DB

120: digital-to-analog converter 130: codec

140: gain margin control unit 150: gain margin generation unit

160: UI control unit 200: audio amplification unit

210: audio amplifier 300: speaker characteristic compensation unit

310: current detection unit 320: frequency detection unit

330: Adder 340: Analog to Digital Converter

400: speaker

The present invention relates to a mobile communication terminal and a method for optimizing the speaker thereof, and more particularly, a gain for determining an amplification magnitude of a sound source signal in a range that guarantees input power and sound quality of a speaker having different characteristics according to a sound source signal of the mobile communication terminal. It is a technology that optimizes speaker characteristics by controlling margins.

Generally, a mobile terminal (hereinafter referred to as a 'terminal') refers to a mobile phone, a palm PC, a personal digital assistant (PDA), or a handheld PC (HPC). It is a high-tech communication device that can perform various tasks through wireless connection as well as network connection without receiving.

Such mobile communication terminals provide various additional services related to audio such as music and video as well as voice communication, and thus, speaker characteristics are becoming more important.

In general, the speaker uses the interaction between the electric field of the electric signal and the magnetic field of the magnet, and the repulsive force and suction force vibrate the air through the vibration of the diaphragm so that the human signal can be recognized.

However, the error may be caused by the deviation of the coil and the defect of the mechanical element such as the vibration plate to convert the electric field signal according to the audio frequency, and a certain gain margin in the design of the mobile communication terminal to reduce such error Apply and tune.

That is, as shown in FIG. 1, the speaker reproduces the sound source signal in the driving region A, and determines the gain margin by setting the optimum point within the range between the maximum power Pmax and the normal power Pnormal.

However, conventionally, when designing a mobile communication terminal, a uniform gain margin is applied to amplify sound source data having different sound powers, thereby exceeding the maximum power Pmax range of FIG. 1 (over-driving; B)), amplification below the normal range (under-driving (B ')) may cause distortion of the speaker and the waveform of the speaker.

An object of the present invention for solving the above problems is to extract the input power and frequency of the different speaker according to the sound source of the mobile communication terminal, and thus the optimum speaker within the range to ensure the maximum power limit and sound quality of the speaker accordingly To ensure the characteristics.

A mobile communication terminal according to the present invention for achieving the above object, a sound source data DB that stores the sound source data, a control unit for amplifying and processing the sound source data according to a predetermined gain margin, and amplifies the sound source data output from the control unit And a speaker characteristic compensator for outputting a gain margin control signal for controlling a gain margin to sense the input current and frequency of the speaker and to compensate for the characteristics of the speaker.

In addition, a speaker optimization method of a mobile communication terminal includes a first process of processing a sound source signal and amplifying according to a predetermined gain margin, a second process of sensing a current value and a frequency of a speaker input terminal, and a detected current value and frequency A third process of outputting and summing each of the first and second compensation signals for the speaker characteristic compensation by using respectively, a fourth process of adjusting the gain margin according to the output signal of the third process, and the adjusted gain margin As a result, a fifth process for amplifying and outputting the sound source signal.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a schematic structural diagram of a mobile communication terminal according to an embodiment of the present invention.

The mobile communication terminal of the present invention includes a sound source data DB 110, a controller 100, an audio amplifier 200, a speaker characteristic compensator 300, and a speaker 400.

The sound source data DB 110 stores sound source data, and the control unit 100 amplifies the stored sound source data according to a predetermined gain margin, and then outputs the processed signal. To this end, the controller 100 includes a digital-to-analog converter 120, a codec 130, a gain margin controller 140, a gain margin generator 150, and a UI controller 160.

The sound source data DB 110 stores sound source data input and recorded through a microphone (not shown) and MP3 and video related sound source data downloaded through an external device.

The digital-to-analog converter 120 amplifies the sound source data output from the sound source data DB 110 according to the gain margin output from the gain margin generator 150, converts the sound source data into an analog signal, and outputs the converted analog signal. To this end, the digital-to-analog converter 120 preferably includes a plurality of amplifiers (not shown) that amplify the sound source data according to a gain margin.

The codec 130 processes an analog sound source signal output through the digital analog converter 120 and outputs processing signals AUXOP and AUXON.

The gain margin controller 140 outputs a gain margin control signal Gain_value for controlling a gain margin according to the output signal of the speaker characteristic compensator 300. In this case, the gain margin control signal Gain_value is controlled to lower the gain margin when the speaker characteristic curve C is higher than the optimum characteristic curve D, and as shown in FIG. 3, to increase the gain margin.

The gain margin generator 150 controls and outputs a gain margin gain according to the gain margin control signal Gain_value.

The UI controller 160 adjusts the gain margin according to the gain margin control signal Gain_value, and applies the same to the melody volume of the UI (unix international) according to the adjusted value to display the user for confirmation.

The audio amplifier 200 includes capacitors C1 and C2, resistors R1 to R5, and an audio amplifier 210. The audio amplifier 210 amplifies and outputs the processing signals AUXOP and AUXON output from the codec 130.

The speaker characteristic compensator 300 includes a current detector 310, a frequency detector 320, an adder 330, and an analog-to-digital converter 340.

The current sensing unit 310 calculates the power of the input terminal of the speaker 400 by measuring the current at both ends of the resistor R5 provided at the input terminal of the speaker 400.

For example, when the maximum power Pmax of the speaker having the optimal characteristics is 0.8W and the normal power Pnormal is 0.5W, the maximum current and the maximum voltage are calculated as in Equation 1 below, and the steady current and the steady voltage are Calculated as Equation 2.

That is, when the current flowing in the input terminal of the speaker 40 is between 0.316 ~ 0.25A, it has an optimum characteristic, but when the current flows smaller than 0.316A or greater than 0.25A, the power value is larger than the maximum power of 0.8W. To this end, the current detector 310 outputs a pulse duration modulation (hereinafter, referred to as a PDM signal). That is, by sensing the current at both ends of the resistor R5 and using the current value (Irms) as shown in Equation 3 below, the power input to the speaker 400 is real-time sampled and measured at a time (t) interval to compensate for the compensation signal accordingly Generate the PDM1 signal.

On the other hand, the frequency detector 320 detects the frequency signal of the input terminal of the speaker 400, and generates a PDM signal.

The adder 330 adds a compensation signal PDM2 signal output from the current detector 310 and the frequency detector 320, and applies it to the gain margin controller 140 through the HKADC pin of the controller 100.

The speaker 400 outputs a signal output through the audio amplifier 210. At this time, the internal resistor R6 is provided inside the speaker 400, and the internal resistance R6 is preferably set to 8 kW.

3 is a waveform diagram comparing and comparing the speaker characteristics C and the ideal characteristics D of FIG. 2.

In the portion E where the speaker characteristic (C) graph is higher than the ideal characteristic (D) graph, the PDM signal is set lower to compensate for the high portion (E) closer to the ideal characteristic (D). On the other hand, in the portion F of which the speaker characteristic (C) graph is lower than the ideal characteristic (D) graph, the PDM signal is set high to compensate the low portion F close to the ideal characteristic (D).

Hereinafter, a speaker optimization method of the mobile communication terminal will be described in detail with reference to FIG. 4.

First, when the sound source data stored in the sound source data DB 110 is reproduced using predetermined software (S100), the sound source data is converted into a digital signal through the digital-to-analog converter 120, and then the signal processing through the codec 130 And amplified by the audio amplifier 210. At this time, the current detector 310 detects the current flowing through the input terminal of the speaker 400 to generate a compensation signal PDM1 signal, and the frequency detector 320 detects the frequency of the input terminal of the speaker 400 and thereby compensates the signal. Generate a PDM2 signal (S300). At this time, the current detector 310 generates a compensation signal PDM1 signal by calculating a power value using the current value.

Subsequently, the adder 330 sums the PDM signals output from the current sensing unit 310 and the frequency sensing unit 320 (S400), and the resultant signal is converted into digital through the analog-to-digital converter 340 to gain. The margin controller 140 is applied to the margin controller 140 to compensate the speaker characteristics by controlling the gain margin (S500), and reproduces the sound source data (S600).

In particular, as shown in FIG. 5, in the method of compensating speaker characteristics by controlling gain margin, first, the gain margin controller 140 determines whether the optimal characteristic curve is greater than the sum of the PDM signals summed (S501), If the sum of the summed PDM signals is smaller than the optimum characteristic curve, the gain margin control signal Gain_value is output to increase the gain margin, and the gain margin generator 150 outputs a high gain margin Gain (S502). In this case, the gain margin control signal Gain_value is output to lower the gain margin, and the gain margin generator 150 outputs a low gain margin Gain (S503).

Accordingly, the digital analog converter 120 amplifies the sound source signal applied from the sound source data DB 110 according to the adjusted gain margin gain.

Therefore, in the present invention, the user extracts sound source data according to the capacity and frequency characteristics of the speaker from the audio data input through the microphone to control the gain margin in a range that guarantees the input power and sound quality of the speaker, and the preset reference By adjusting the input sound pressure of the speaker that is adjusted to, it prevents potential damage due to excessive current inflow and minimizes distortion of the joints and waveforms caused by excessive over-driving for optimum sound quality.

As described above, the present invention senses the current and frequency of the speaker input terminal of the mobile communication terminal to control the gain margin within the range to ensure the maximum input power and sound quality to ensure optimal performance and damage due to excessive current inflow There is an effect that can prevent.

In addition, a preferred embodiment of the present invention is for the purpose of illustration, those skilled in the art will be able to various modifications, changes, replacements and additions through the spirit and scope of the appended claims, such modifications and changes are the following claims It should be seen as belonging to a range.

Claims (6)

A sound source data DB for storing sound source data; A controller for amplifying and processing the sound source data according to a predetermined gain margin; An audio amplifier for amplifying the sound source data output from the controller and outputting the amplified data to a speaker; And And a speaker characteristic compensator configured to sense an input current and a frequency of the speaker and output a gain margin control signal for controlling the gain margin to compensate for the speaker characteristic. The method of claim 1, wherein the control unit, A gain margin controller configured to output the gain margin control signal based on a signal output from the speaker characteristic compensator; A gain margin generator for adjusting the gain margin according to the gain margin control signal; A digital analog converter for amplifying the sound source data and converting the sound source data into a digital signal according to the adjusted gain margin; And And a codec for signal processing an output signal of the digital analog converter. The method of claim 1, wherein the speaker characteristic compensator, A current sensing unit configured to sense current from an input terminal of the speaker, calculate power, and generate a first compensation signal; A frequency detector configured to detect a frequency of an input terminal of the speaker and generate a second compensation signal; An adder for adding the first compensation signal and the second compensation signal; And And an analog-to-digital converter for converting the output signal of the adder into a digital signal. A first process of processing the sound source signal and amplifying the sound signal according to a predetermined gain margin; Detecting a current value and a frequency of the speaker input terminal; A third process of outputting and summing first and second compensation signals for speaker characteristic compensation by using the sensed current value and frequency, respectively; A fourth step of adjusting the gain margin according to the output signal of the third step; And And a fifth process of amplifying and outputting the sound source signal according to the adjusted gain margin. The method of claim 4, wherein the third process comprises: Step 3-1 of calculating a speaker input power using the sensed current value and outputting the first compensation signal according to the result; A third step of outputting the second compensation signal using the sensed frequency; And And a third to third summation of the first compensation signal and the second compensation signal. The method of claim 4, wherein the fourth process, The gain margin is lowered if the level of the output signal of the third process is higher than the speaker characteristic optimization curve; and the gain margin is increased if the level of the output signal of the third process is lower than the speaker characteristic optimization curve. Method for optimizing speaker characteristics of a communication terminal.

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