Patent Publication Number: US-2010114343-A1

Title: Audio processing system

Description:
BACKGROUND  
     1. Technical Field 
     The present disclosure relates to audio processing technology and, particularly, to an audio processing system, which can provide high audio effects. 
     2. Description of Related Art 
     An audio apparatus may receive external audio signals from an external audio inputting apparatus via an input/output (I/O) processing unit, such as an audio jack. The external audio signals may be outputted to speakers of the audio apparatus. However, before the external audio signals outputting to the speakers, the external audio signals may be attenuated by other circuits of the audio apparatus, such as a sound source circuit that is coupled to the audio jack. Thus, the audio quality of the audio apparatus may not be acceptable. 
     Therefore, what is needed is an audio processing system, which can provide high audio effects in an audio system. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The FIGURE is a functional block diagram of an audio processing system, according to an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to the FIGURE, an audio processing system  100  is used in an audio device, such as a portable digital versatile disc (DVD) player, according to an exemplary embodiment. The audio processing system  100  includes an input unit  10 , a control unit  20 , an audio reproducing unit  30 , a storage unit  40 , a switch unit  50 , an outputting unit  60 , and an input/output (I/O) processing unit  70 . 
     The input unit  10  is configured to receive instructions from a user and generate a first signal or a second signal. The input unit  10  may be a switch which is switchable between a first state and a second state. When the switch is switched to the first state, the input unit  10  electrically connects to a power source and generates the first signal. When the switch is switched to the second state, the input unit  10  electrically connects to ground and generates the second signal. 
     The control unit  20  is configured to generate a first trigger signal or a second trigger signal, according to the first signal or the second signal, respectively. 
     The storage unit  40  stores a plurality of audio files, a current gain value V, or other data. The storage unit  40  can be selected from a group consisting of a flash memory storage, a hard disk drive, an optical disk, etc. 
     The audio reproducing unit  30  is configured to respond to the first trigger signal, decode the plurality of audio files retrieved from the storage unit  40 , and generate internal audio signals to the switch unit  50 . In this case, the audio reproducing unit  30  includes a decoder  31 , a digital to analog (D/A) converter  33 , and an operational amplifier  35 . The decoder  31  is configured to decode the plurality of audio files retrieved from the storage unit  40 , and to generate digital audio signals correspondingly. The D/A converter  33  is configured to convert the digital audio signals to analog audio signals. The operational amplifier  35  is configured to amplify the analog audio signals according to the current gain value V, and to transmit the amplified analog audio signals as the internal audio signals. 
     The switch unit  50  is configured to selectively establish the connection between the audio reproducing unit  30  and the I/O processing unit  70 . When the I/O processing unit  70  is selected to output internal audio signals to a first external device  81  according to the first trigger signal, the switch unit  50  is switched on and establishes the connection between the audio reproducing unit  30  and the I/O processing unit  70 . When the I/O processing unit  70  is selected to input external audio signals from a second external device  83  according to the second trigger signal, the switch unit  50  is switched off and disables the connection between the audio reproducing unit  30  and the I/O processing unit  70 . The switch unit  50  can be a switch integrated circuit (IC), thereby the switch unit  50  can be controlled by the control unit  20  more easily and automatically. An electrical node  51  is formed by the switch unit  50 , the outputting unit  60  and the I/O processing unit  70  cooperatively. 
     The outputting unit  60  is configured to output the internal audio signals according to the first trigger signal, and output the external audio signals according to the second trigger signal. The outputting unit  60  includes an amplify sub-unit  61  and a speaker  63 . The amplify sub-unit  61  is configured to amplify the internal or external audio signals to activate the speaker  63  to output sound. The amplify sub-unit  61  can be a power amplifier. 
     The I/O processing unit  70  is configured to selectively output the internal audio signals to the first external device  81  according to the first trigger signal, and to input external audio signals from the second external device  83  according to the second trigger signal. The first external device  81  can be an amplifier or a headset, or similar output devices. The second external device  83  can be a microphone or a similar input device. The I/O processing unit  70  includes a filtering sub-unit  71  and an I/O sub-unit  73 . The filtering sub-unit  71  is configured to filter the internal audio signals from the switch unit  50  or to filter the external audio signals from the I/O sub-unit  73 . The I/O sub-unit  73  is configured to transmit the internal audio signals from the filtering sub-unit  71  to the first external device  81 , or to transmit the external audio signals from the second external device  83  to the filtering sub-unit  71 . The filtering sub-unit  71  can be a filter circuit. The I/O sub-unit  73  can be an audio jack. 
     In this embodiment, the audio processing system  100  is in a first mode for outputting internal audio signals according to the first signal, and the audio processing system  100  is in a second mode for receiving external audio signals according to the second signal. When the input unit  10  generates the first signal, the audio processing system  100  is in the first mode, and the control unit  20  responds to the first signal to generate the first trigger signal. According to the first trigger signal, the audio reproducing unit  30  generates the internal audio signals, which the internal audio signals are decoded from the plurality of audio files retrieved from the storage unit  40 , and the switch unit  50  is switched on to establish the connection between the audio reproducing unit  30  and the electrical node  51 . Thus, the speaker  63  and the I/O sub-unit  73  can output the internal audio signals. 
     When the input unit  10  generates the second signal, the audio processing system  100  is in the second mode, and the control unit  20  responds to the first signal to generate the second trigger signal. According to the second trigger signal, the switch unit  50  is switched off to disable the connection between the audio reproducing unit  30  and the electrical node  51 . As a result, the outputting unit  60  selectively outputs the external audio signals from the second external device  83 . The external audio signals are not affected by the audio reproducing unit  30 . Thus, the sound quality is improved. 
     It is to be understood, however, that even though numerous has been described with reference to particular embodiments, but the present invention is not limited to the particular embodiments described and exemplified, and the embodiments are capable of considerable variation and modification without departure from the scope of the appended claims.