JP2001265360A - Portable digital media reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a portable digital media reproducing device in small-sized and lightweight structure which is easy to carry by reducing the weight and size. SOLUTION: This portable digital media reproducing device is applied with electric power and digital from external equipment by having a connector part equipped with plural power input terminals which are connected to at least two kinds of external equipment and receive the electric power from the external equipment, a digital data transmission terminal for sending and receiving digital data to and from the external equipment, and a terminal applied with a section control signal for classifying the kind of the external equipment, a power distribution part which supplies the electric power supplied from the external equipment through the connector part to respective function blocks, and an interface part which sends and receives the digital data adaptively to the kind of the external equipment by controlling the transmission speed with the external equipment classification control signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to MP3 and AA.
C and other portable digital media playback devices (Portab
le digital media playback apparatus), more specifically, without a power supply inside the main body, connected to an external device including a mobile phone and a computer using a connection connector to drive a portable digital media playback apparatus. The present invention relates to a portable digital media playback device that receives a power supply required for an electronic device and receives additional functions and the like.

[0002]

2. Description of the Related Art A digital media reproducing apparatus according to the prior art has a structure in which a battery power supply is indispensably installed in a main body, and the size and weight occupied by the battery power supply are smaller than those of a portable digital media reproducing apparatus. This is a factor that limits the reduction in weight and weight, and frequent replacement of the battery is economically burdensome and time-consuming. In addition, digital audio storage device (Voice Recorder) and digital media playback device,
Further, when it is necessary to operate between portable devices such as mobile phones that are widely used, for example, while making a call using a mobile phone, at the same time, storing the contents of the call in a digital voice storage device, The operation of transmitting the reproduced sound from the digital media reproducing apparatus to the other party of the mobile phone by mixing the transmitted sound with the transmitted sound has been inconvenient and difficult.

[0003]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and has a structure capable of receiving power from an external device such as a mobile phone or a computer. Accordingly, it is an object of the present invention to provide a portable digital media playback device having a simple, compact, and lightweight structure that is easy to carry with reduced weight and size.

It is an object of the present invention to provide a portable digital media reproducing apparatus having a connector structure for automatically detecting a connection between a computer communication port and a communication port of a mobile phone.

A further object of the present invention is to provide a portable digital device having a mixer section comprising a simple circuit for synthesizing a signal generated from a digital media reproduction signal and a signal inputted from an external device such as a portable telephone. A media playback device is provided.

It is another object of the present invention to provide a portable digital media reproducing apparatus having a terminal configuration for minimizing interference between an analog signal and a digital signal input from an external device.

[0007]

SUMMARY OF THE INVENTION The object of the present invention is to achieve
In an apparatus for digital media playback including P3 and AAC, a plurality of power supply terminals connected to at least two types of external devices and receiving power supplied from the external devices; A connector having a terminal for transmitting and receiving digital data for transmission and reception and a terminal for receiving a division control signal for classifying the type of the external device; and a functional block for supplying power supplied from the external device through the connector. A power distribution unit for supplying power to the external device; and an interface unit for controlling a transmission rate of digital data by a division control signal applied from the external device through the connector and transmitting / receiving digital data from the external device. Power and digital data from at least two external devices It can be achieved by a portable digital media playback apparatus characterized by can receive.

[0008] The connector applied to the portable digital media playback apparatus of the present invention further includes a terminal for receiving an analog signal, and is configured to receive a control signal for distinguishing the external device from the connector. By doing so, the external devices attached to the digital media playback device can be classified.

The portable digital media reproducing apparatus of the present invention includes a mixer section for mixing an analog signal input from an external device with an electric signal reproduced from a memory section of the portable digital media reproducing apparatus. It has become possible to record the details of a call made by a mobile phone and to send out the playback sound of a digital media playback device to the mobile phone.

An object of the present invention is that at least one of a plurality of power supply input terminals is disposed at a center, and the plurality of analog signal transmission / reception terminals and the plurality of digital data transmission / reception terminals are adjacent to each other. Meanwhile, the power terminals arranged in the center are arranged on opposite sides with respect to the center,
At least one of the remaining power input terminals other than the power input terminal disposed at the center is disposed outside the plurality of analog signal transmission / reception terminals and the plurality of digital data transmission / reception terminals. The present invention can also be achieved by a portable digital media playback device having a connector.

According to another aspect of the present invention, there is provided a memory unit for storing a digital media file for reproduction, a control program and data generated internally during operation, and a digital media data stored in the memory unit. A DSP processing unit for decompressing the digital data transmitted from the external device in real time and compressing the digital data transmitted from the external device in real time, an A / D conversion unit for converting an analog signal input from an audio input terminal or an external device into a digital signal, A D / A converter for converting a digital signal reproduced from the DSP processor into an analog signal, a control keypad for receiving a user input for changing a digital media operation state, A display unit for notifying, the control keypad unit, and the display unit. Interface interface for processing digital data between the general-purpose interface unit and the USB device, an audio output terminal for outputting audio signals generated from the device, and audio for inputting external audio signals to the device A mixer for controlling and calculating a data flow between the input terminal and each functional block, wherein the mixer unit is connected to a D / A conversion unit output terminal;
An input terminal 121, a second input terminal 122 for receiving an electrical signal input from the audio output terminal of the external device through the connector, and a first output terminal 123 for combining these input signals and outputting the combined signal. And the first
The output terminal 123 is connected to the audio output terminal of the present apparatus, and the third input terminal 132 receives an electrical signal input from the audio output terminal of the external device.
And a fourth input terminal 131 for receiving an electric signal input to the audio input terminal of the device and a second output terminal 133 for synthesizing these input signals and outputting them. Is connected to the A / D converter, the fifth synthesizer 130 is connected to an electrical signal input to the audio input terminal of the device, and the fifth input terminal 141 is connected to the D / A converter. A third synthesizing unit 140 including a sixth input terminal 121 and a third output terminal 143 for synthesizing and outputting these input signals, and a third output terminal 143 of the third synthesizing unit and an audio input terminal of the external device. Provided in
The present invention can be achieved by a portable digital media playback device including a first analog switch that determines whether to open or close according to a mixer control signal output from the general-purpose interface unit.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically with reference to the drawings. FIG. 1 is a system configuration diagram of a portable digital media playback device according to an embodiment of the present invention.
PU 20, decoder processing unit 30, microphone (MIC) 40 for receiving sound input from outside, speaker (SPK) 50 for outputting sound to outside, connector 60 for connecting to external digital devices such as a mobile phone or a computer, external Power distribution unit (Power Distributor) 110, U for supplying power applied from the device to each functional block
A USB interface part (USB Interface Part) 70 for transmitting and receiving digital data to and from external devices connected to an SB (Universal Serial Bus) and a normal input / output signal processing, and transmitting and receiving digital data to and from other external devices. General-purpose interface section (General
Purpose Interface Part) 80, a control keypad unit 90 for receiving an external user input, and a display unit 100 for displaying the state of the digital media playback device to the user. The decoder processing unit 30 includes a DSP processing unit 31, an A / D and D / A conversion unit (Analog to Digital Converter & Digita).
1 to Analog Converter) 32, a mixer unit 33, a microphone amplifier 34, and a speaker amplifier 35. As shown in FIG. 1, the decoder processing unit 30
It can be provided on one chip or can be configured on a plurality of chips.

In the above configuration, the CPU 20 controls the operation of the entire system and
The system performs a system operation program such as automatically detecting connection of external devices and executing a corresponding communication program. The memory unit 10 stores a system control program such as a download program, a voice and call recording program, and a communication program, and a ROM 12 that stores data used for system operation.
M) 11, a flash memory 13 for storing digital media data or audio. The decoder processing unit 30 combines the signals input from the two sources using the mixer unit 33, and performs A / D
And a digital / analog converter for converting audio analog signals into digital data, converting digital data to analog signals, or using a DSP processing unit 31 to decompress digital media data in real time by a control signal of the CPU 20. It plays back and converts audio signals input from external devices into digital data and then compresses them.

The USB interface unit 70 is a circuit for transmitting and receiving digital data to and from an external device connected to the USB according to a control signal of the CPU 20 generated according to the type of the external device. At the time of connection, digital data transmitted to and received from the DP terminal 65 and the DM terminal 66 of the connector unit 60 is input to the memory unit 10 at a transmission rate of 12 Mbps using the data bus of the CPU 20 by a control signal of the CPU 20 at the time of connection. Function to output. Since such a circuit configuration is a well-known technology for a circuit that performs serial data transmission and reception with an external device connected to the USB, detailed circuit technology is omitted.

The control keypad section 90 allows the user to play digital media, search for media before and after,
Recording and voice recording during a call, and when connecting to a mobile phone, input to control the function of mixing and transmitting the digital media playback sound with the transmission sound during the call, and the digital media download function An input device for receiving.

The display section 100 is a display section for informing the user of the state of the digital media reproducing apparatus.
The general-purpose interface unit 80 is connected to the control keypad unit 90 and the display unit 100 to perform input / output, transmits a sorting control signal generated from a connector to the CPU 20 according to the type of external device, and is connected to the mobile phone. When a call is made in this state, a control signal for bringing the analog switch of the mixer unit 33 into a connected state (Close) is output and transmitted to the mixer unit 33, and other terminals including the serial communication ports Rx and Tx are provided. When connected to an external device, it is responsible for transmitting and receiving digital data. The general-purpose interface unit 80 can be implemented with the CPU 20 and a single chip.

The connector 60 connects an external device such as a mobile phone or a computer to a digital media reproducing apparatus, and is a connecting portion for transmitting and receiving power supplied from the external device, digital data and / or analog signals. The power supplied from the external device through 60 is distributed to each functional block through a power distribution unit (Power Distributor) 110. That is, the power distribution unit 110 adjusts the voltage level to be applied to each functional block using the power input from the external device, and
Function of distributing power to each circuit functional block. As the power distribution unit 110 used in the present invention, a TEA 1202TS chip manufactured by Philips was used.

FIG. 2 is an explanatory view of a use state of the portable digital media reproducing apparatus of the present invention. The portable digital media reproducing apparatus is connected to a portable telephone through a connection connector A160, and 1) power is applied. 2) In the case of a mobile phone capable of data communication, the digital media is downloaded using the Internet communication network and then stored in the memory unit 10 of the digital media playback device,
Or 3) using the microphone terminal (FIG. 3) 62 and the headphone terminal (FIG. 3) 63 of the portable digital media playback device to transmit / receive a mobile phone call, record during a call, and play digital media playback sound during a call. It becomes possible to perform a function of transmitting the sound by mixing with the transmission sound. When connected to the UART of the mobile phone, transmission and reception of digital data is performed by the CPU 2
0 control signal, the DP terminal 65 of the connector unit 60
And R of the DM terminal 66 and the general-purpose interface unit 80
115.2k using connection of x and Tx serial communication terminals
Digital data is transmitted and received at a rate of bps or 230.4 kbps.

The portable digital media playback device is connected to a computer through a connection connector B170,
1) receiving a power supply necessary for driving the digital media; and 2) performing a function of receiving a download of the digital media from a computer.

When connected to a USB port of a computer, digital data is transmitted to and received from a DP terminal 65 and a DM terminal 66 of a connector unit 60 by a control signal of the CPU 20, and then input to a USB interface unit 70. The USB interface unit transmits and receives digital data using a transmission protocol (12 Mbps) and a transmission protocol compatible with USB. USB interface 7
The digital data of 0 is input to and output from the memory unit 10 at a transmission rate of 12 Mbps using the data bus of the CPU 20.

At this time, the moving path of the digital data is determined by the external device classification control signal (USB / UART control signal in FIG. 1) generated from the connector 60.
0 will be used. As described above, the power input through the connector 60 is supplied to each functional unit after being converted to an appropriate voltage level by the voltage distribution unit 110.

FIG. 3 is a diagram showing a connector structure of the digital media reproducing apparatus of the present invention. An external connection terminal 61 for connecting to an external device includes a microphone terminal (MIC) 62 for transmitting and receiving analog signals and a speaker terminal. (SP
K) 63 and power supply terminals (Vcc, GND) 64, 67
Digital data transmission / reception terminals (DP, DM) 65, 66
Consists of Analog signal transmission / reception terminals 62, 63
Is applied to the decoder processing unit 30, and among the analog signal terminals, the speaker terminal 63 is connected to the interface unit 80 as a control generation terminal for distinguishing an external device. The speaker terminal 63 is connected to a ground and a resistor having a relatively large value before being connected to the internal function block of the present device, thereby preventing leakage current and at the same time preventing external devices connected to the digital media playback device. A voltage for classifying the type is applied. That is, when connected to a mobile phone, the output of the speaker is 0 volts or ± several tens of mV
A "LOW" voltage having an output of ± several hundred nV or less is applied, and when connected to a computer, a "HIGH" voltage is applied. General-purpose interface unit 80
Represents the voltage applied to the speaker terminal 63 by the CPU 20.
After reading this, the CPU 20 applies an appropriate control signal to the USB interface unit 70 or the general-purpose interface unit 80 to select an appropriate communication speed and communication path.

Power supply terminals (Vcc, GND) 64, 6
7 is connected to a power distribution unit (Power Distributor) 110 to supply power of an external device to each functional unit of the digital media playback device, and digital data transmission / reception terminals (DP, DM) 65 and 66 are connected to a USB. By being connected to the interface unit 70 and the general-purpose interface unit 80, digital media data can be efficiently transmitted and received from an external device.

FIG. 4 is a circuit diagram of a mixer section of the digital media reproducing apparatus according to the present invention. Mixer section 33
Is a first combining unit 120 having two input and one output terminals,
It comprises a combining unit 130, a third combining unit 140, and a first analog switch 150. The first input terminal 121 and the second input terminal 122 of the first synthesis unit 120
The output terminal of the first synthesizing unit 120 is connected to the output terminal of the / A conversion unit 32 and the speaker terminal 63 of the connector 60.
3 is connected to the input terminal of the speaker amplifier 35. The third input terminal 132 and the fourth input terminal 131 of the second synthesis unit 130 are connected to the speaker terminals 63 of the connector 60, respectively.
The output terminal 133 of the second synthesis unit 130 is connected to the input terminal of the A / D conversion unit 32. Fifth input terminal 141 of third combining section 140
And the sixth input terminal 121 are connected to the microphone amplifier 34, respectively.
Is connected to the output terminal of the D / A converter 32,
The output terminal 143 of the combining unit 140 is connected to one end of the first analog switch 150. 1st analog switch 1
The other end of the connector 50 is connected to the microphone terminal 62 of the connector 60, and the necessity of opening and closing is determined by a mixer control signal. The microphone terminal of the connector 60 is connected to the audio input terminal of the external device, and the speaker terminal of the connector 60 is connected to the audio output terminal of the external device.

When the user activates the "play" button on the control keypad, the first analog switch is opened and the MP3 is stored in the memory unit 10.
Alternatively, digital media data stored in a compressed state in the form of an AAC bit stream is transmitted to a DSP processor 3.
After decompression, the signal is reproduced as an analog signal using the D / A converter 32, and thereafter, is input to the speaker amplifier 35 via the first synthesizing unit 120 and amplified. After converting to, users will be able to listen. here,
The speaker amplifier 35 and the speaker 50 function as an audio output terminal of the device, and the microphone 40 and the microphone amplifier 34
Performs the function of the audio input terminal of this device.

When the digital media playback device of the present invention is connected to a mobile phone, a telephone call can be made using the connected microphone 40 and headphones 50 using the digital media playback device. If a call comes in through a mobile phone during the playback operation of the digital media playback device,
The first analog switch 15 is controlled by the mixer control signal.
0 is closed.

When a call signal for making a call to the mobile phone arrives, such a signal is transmitted to the connector A16.
Using 0, the digital data is input to the digital data transmission / reception terminals (DP, DM) 65 and 66 of the connector unit 60 and then applied to the general-purpose interface unit 60. The general-purpose interface unit 80 transmits a call signal to the CPU 20. C
The PU 20 generates a mixer control signal (MixerControl Signal) through the general-purpose interface unit 80, and the generated control signal closes the first analog switch 150 of the mixer unit 33. The mobile phone senses this using an internal function circuit and switches to a call state.

During a mobile phone call, the first analog signal 150 is closed by the mixer control signal.
Is output to the speaker amplifier 35 through the first synthesizing unit 120, so that the user can check the contents of the call voice output. At this time, when the digital media playback device is in a state of continuous playback, the output of the D / A conversion unit 32 is output to the first synthesis unit 12.
Since 0 is combined with the call voice output, the user can listen to a synthesized signal of the contents of the call and the reproduced signal of the digital media playback device.

In this case, the details of the call that the user intends to transmit through the microphone 40 are input to the microphone terminal 62 of the connector 60 through the third combining unit 140,
It is transmitted to the other party through the mobile phone. At this time, if the digital media playback device is continuously playing,
The reproduction signal of the digital media output from the D / A conversion unit 32 is combined with the details of the communication to be transmitted by the third combination unit 150, and then transmitted to the other party.

The recording of the contents of the call is performed after the user's voice signal output from the microphone 40 and the other party's voice signal input from the speaker terminal 63 of the connector 60 are synthesized by the second synthesis unit 130, This is possible by inputting to the D conversion unit 32. The input call contents are compressed by the DSP processing unit and then stored in the memory unit 10.
Stored in

FIG. 5 is a connection structure diagram of an external connection terminal 61 of the digital media reproducing apparatus and a connection connector A160 connected to a communication terminal (UART) of a mobile phone. The connection connector A includes a microphone (MIC) terminal of a mobile phone and a microphone (MIC) terminal of a digital media playback device, a speaker terminal of a mobile phone and a speaker terminal of a digital media playback device, a VDD power terminal of a mobile phone and a digital media playback device. Vcc power supply terminal, digital data transmission terminal (TXD) of mobile phone and DP terminal among digital data terminals of digital media playback device, digital data transmission terminal (RXD) of mobile phone and DM terminal among digital data terminals of digital media playback device. The ground power supply terminal, the nRFR terminal, and the nCTS terminal of the mobile phone are connected to the ground power supply terminal of the digital media player. The terminal configuration connected to the mobile phone shown in FIG. 5 may be different depending on the type of the mobile phone. That is, the nRFR terminal and the nCTS terminal are special terminals used in a mobile phone terminal of “LG information communication” which is one of the electronic companies in Korea.

FIG. 6 is a diagram showing a connection structure of a connection connector B170 for connecting the external connection terminal 61 of the digital media reproducing apparatus to the communication terminal (USB) of the computer.
The connection connector B170 includes a computer VDD power terminal and a Vcc power terminal of the digital media reproducing device, a computer digital data D + terminal and a DP terminal among digital data terminals of the digital media reproducing device, a computer digital data D− terminal and a digital terminal of the digital media reproducing device. The DM terminal among the data terminals and the ground power supply terminal of the computer are respectively connected to the ground power supply terminal of the digital media playback device. Particularly, the VDD power supply terminal of the computer is connected to the speaker (SPK) terminal of the digital media playback device. Digital media playback device speakers (S
(PK) terminals.

FIG. 7 is an enlarged view of a port portion inserted into the external connection terminal 61 of the portable digital media reproducing apparatus of the present invention in the configuration of the connection connector A160 and the connection connector B170. At the center, a microphone (MIC) and a speaker (S
PK), a digital signal terminal composed of digital data DP and DM is disposed below the analog signal terminal, and a ground terminal is disposed outside the digital signal terminal. By arranging the power supply terminal at the center between the analog signal input terminal and the digital signal input terminal as shown in FIG. 7A, interference between the applied analog signal and digital signal can be minimized.

FIG. 7B shows an equivalent circuit in the case where the power supply terminals are not arranged between the digital data terminals and the analog signal terminals but are arranged adjacent to each other. That is, the analog signal terminal and the digital data terminal each form one plate of the capacitor. In the drawings, the analog signal terminal can be displayed on the plate A and the digital data terminal can be displayed on the plate D. When A is a digital signal and D is an analog signal, the AC (alternating current) component of the digital signal affects D, and conversely, the alternating current component of D affects A. In the latter case, the voltage level of the digital signal is relatively large, so there is no significant effect because it is less affected.However, in the former case, the analog signal is more affected by the digital signal, which causes undesirable noise. Become.

Therefore, as shown in FIG. 7A, when the pin arrangement is formed, it is recognized as an equivalent circuit as shown in FIG. 7C. At this time, the AC component of the terminal D passes through the capacitor and becomes Vcc. Or it flows to the ground terminal,
It has no effect on the signal applied to terminal A, and the same is true for the opposite case.

[0036]

According to the portable digital media reproducing apparatus of the present invention, power can be supplied from an external device, so that a small and lightweight portable digital media reproducing apparatus which does not require a separate power supply apparatus. Equipment can now be provided.

Further, the portable digital media reproducing apparatus of the present invention has a connector for automatically detecting the connection between the computer communication port and the communication port of the mobile phone, so that it can be freely connected to the computer or the mobile phone. Can now be connected.

By providing a mixer unit that can combine an audio signal generated from the digital media playback device of the present invention with an audio signal input from an external device such as a mobile phone, the digital media playback device reproduces the audio signal. There is an advantage that the transmitted signal can be freely transmitted using a wireless data communication device such as a mobile phone.

The digital media reproducing apparatus having the connection terminal configuration proposed in the present invention can minimize the interference between the analog signal and the digital signal input from the external device, so that high-quality digital media can be reproduced. It is now possible.

The present invention has been described with reference to the embodiments shown in the drawings. However, this is merely an example, and those having ordinary knowledge in the technical field of the present invention may
From this, it should be understood that various modifications and equivalent alternative embodiments are possible. Therefore, the true protection scope of the present invention should be determined by the spirit of the appended claims.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a portable digital media playback device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a use state of the portable digital media playback device of the present invention.

FIG. 3 is a configuration diagram of a connector of the digital media playback device of the present invention.

FIG. 4 is a circuit configuration diagram of a mixer section of the digital media playback device of the present invention.

FIG. 5 is a connection structure diagram of a connection connector A for connecting a digital media playback device of the present invention to a communication terminal (UART) of a mobile phone.

FIG. 6 is a connection connector B for connecting the digital media playback device of the present invention to a communication terminal (USB) of a computer.
FIG.

FIG. 7 is an enlarged view of a port portion of the configuration of the connection connector A and the connection connector B of the present invention, which is inserted into the external connection terminal 61 of the mobile phone digital media playback device of the present invention.

[Explanation of symbols]

 Reference Signs List 10 memory unit 20 CPU 30 decoder processing unit 33 mixer unit 40 microphone (MIC) 50 speaker (SPK) 60 connector 70 USB interface unit 80 general-purpose interface unit 90 control keypad unit 100 display unit 110 power distribution unit 120 first synthesis unit 130 Second combining unit 140 Third combining unit 150 First analog switch 160 Connector A 170 Connector B

Claims (7)

[Claims] 1. An apparatus for playing digital media including MP3 and AAC, comprising: a plurality of power input terminals connected to at least two types of external devices and receiving power supplied from the external devices; A connector having a terminal for transmitting and receiving digital data for transmitting and receiving digital data to and from an external device and a terminal for receiving a division control signal for classifying the type of the external device; A power distribution unit for supplying power to each functional block; and a transmission / reception unit for controlling digital data transmission speed by a division control signal applied from the external device through the connector. By providing an interface unit, power can be supplied from at least two types of external devices. Portable digital media playback apparatus characterized by capable of receiving the application of digital data. 2. The connector unit further comprises a plurality of analog signal transmission / reception terminals for receiving analog signals, and a division control signal of the external device is applied through the analog signal transmission / reception terminals. The portable digital media playback device according to claim 1, wherein: Wherein at least one of the plurality of power input terminals is disposed at the center, and the plurality of analog signal transmission / reception terminals and the plurality of digital signal transmission / reception terminals are adjacent to each other, 3. The portable digital media reproducing apparatus according to claim 2, wherein the power supply terminals are disposed on opposite sides of the power supply terminal disposed at the center. 4. A power input terminal other than the power input terminal disposed at the center, at least one of which is located outside of the plurality of analog signal transmission / reception terminals and the plurality of digital signal transmission / reception terminals. The portable digital media playback device according to claim 3, wherein the device is arranged. 5. The apparatus according to claim 1, wherein at least one of the plurality of analog signal input terminals includes a resistor connected to a ground unit before being connected to an internal function block. 5. The portable digital media playback device according to 2, 3, or 4. 6. The apparatus of claim 2, further comprising a mixer for mixing an analog signal input from the external device through the connector and an analog signal reproduced inside the portable digital media reproducing apparatus. Portable digital media playback device. 7. A memory unit for storing a digital media file for reproduction, a control program, and data generated internally during operation, decompressing the digital media data stored in the memory unit in real time, DS that compresses digital data transmitted from external equipment in real time
An A / D conversion unit for converting an analog signal input from a P processing unit and an audio input terminal or an external device into a digital signal, and a D / A conversion unit for converting a digital signal reproduced from the DSP processing unit into an analog signal A control keypad unit for receiving a user input for changing an operation state of the digital media; a display unit for notifying the operation state of the digital media to the outside; and interfacing with the control keypad unit and the display unit. Universal interface and USB
A USB interface unit for processing digital data with the device, an audio output terminal for outputting an audio signal generated from the device, an audio input terminal for inputting an external audio signal to the device, and data between functional blocks. A mixer for controlling and calculating the flow of the data, wherein a mixer is input from a first input terminal (121) connected to the output terminal of the D / A converter and an audio output terminal of the external device through the connector. A second input terminal (122) for receiving an input of an electrical signal and a first output terminal (123) for synthesizing and outputting these input signals are provided. The first output terminal (123) is A first synthesizing unit connected to the audio output terminal; a third input terminal for receiving an electric signal input from an audio output terminal of the external device; Input terminal (13) for receiving an electric signal input to the audio input terminal of the device.
1) and a second output terminal (133) for synthesizing these input signals and outputting them.
3) is connected to the A / D conversion unit by a second synthesis unit (13).
0); a fifth input terminal (141) connected to an electric signal input to the audio input terminal of the device, a sixth input terminal (121) connected to the D / A converter, and these input signals. And a third output terminal (14
And a mixer control provided between the third output terminal (143) of the third synthesis unit and the audio input terminal of the external device and output from the general-purpose interface unit. 7. The portable digital media playback device according to claim 6, further comprising a first analog switch that determines whether to open or close according to a signal.