Audio controller for portable electronic devices

• US 7,444,439 B2
• Filed: 09/09/2003
• Issued: 10/28/2008
• Est. Priority Date: 03/26/1998
• Status: Expired due to Fees

• Current Assignee: Maishi Electronic (Shanghai) Limited
• Original Assignee: O2 Micro International Limited (O2 Micro Incorporated)
• Inventors: Du, Sterling Shyun-Dii, Chan, Reginia
• Primary Examiner(s): Park, Ilwoo
• Application Number:
  US10/658,229
• Publication Number:
  US 20060101175A1
• Time in Patent Office: 1,876 Days
• Field of Search: None
• US Class Current: 710/14
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3256 Power saving in optical drive
• CPC Class Codes: G06F 3/165 Management of the audio stream, e.g. setting of volume, audio stream path
• CPC Class Codes: G11B 20/00007 Time or data compression or expansion audio compression based on psychoacoustics G10L19/00; data processing for reproducing audio data at different playback speeds G10L21/04; video compression H04N19/00; data compression per se H03M7/30
• CPC Class Codes: G11B 20/10 Digital recording or reproducing
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

An audio controller for use with laptop and notebook digital computers for reproducing compressed digital audio recordings. The controller includes a drive interface for traversing and accessing audio data files stored on a drive of a computer system. Function keys coupled to the controller permit users to access drives containing desired audio data. The selected audio data is read from the drive into the controller. Decoding circuitry decodes the audio data and generates a decoded audio data stream. The data stream can be converted to an analog signal by the controller, or sent to the audio subsystem of the computer system. Advantageously, the controller operates when the computer system is in an inactive state, for example in power saving mode or OFF, and operates in passthrough mode when the computer system is ON or active.

Claims

1. A controller for enabling a plurality of audio files to be played on a computer subsystem of a computer system if said computer system is in an inactive state, said controller comprising:

a switch having a first state and a second state, wherein said switch in said first state decouples said controller from said computer subsystem and from an audio integrated circuit (IC) coupled to said computer subsystem, wherein said audio IC is configured to play said plurality of audio file if said switch is in said first state, and wherein said switch in said second state couples said controller to said computer subsystem in response to said computer system being in said inactive state;

a drive interface configured to interface with a drive of said computer subsystem depending on a state of said switch, wherein said drive interface is configured to access audio data on said drive if said switch is in said second state; and

decoder circuitry for providing an audio signal to a speaker so as to play said plurality of audio files if said switch is in said second state, wherein said speaker is selectively coupled to said audio IC and said decoder circuitry according to said state of said switch.

2. The controller of claim 1, wherein said audio data comprises compressed audio data, and wherein said decoder circuitry is configured to receive said compressed audio data and to output decompressed audio data.

3. The controller of claim 2, wherein said decoder circuitry comprises a buffer memory for temporarily storing said decompressed audio data.

4. The controller of claim 3, wherein said buffer memory comprises a first-in-first-out (FIFO) memory.

5. The controller of claim 2, wherein said decoder circuitry comprises a digital to analog circuit for receiving said decompressed audio data and for generating an analog audio signal.

6. The controller of claim 2, wherein said decoder circuitry comprises an interface circuit for receiving said decompressed audio data and for communicating with an external digital to analog converter.

7. The controller of claim 2, further comprising:

a processor for controlling said state of said switch and for controlling said decoder circuitry.

8. The controller of claim 7, further comprising:

a flash memory for storing data and a plurality of commands,

wherein said data and said plurality of commends are used by said processor for controlling said decoder circuitry.

9. The controller of claim 1, further comprising:

a liquid crystal display (LCD) interface for generating at least one signal to an LCD display,

wherein said LCD display displays directory data associated with said drive.

10. The controller of claim 1, further comprising:

a function key interface responsive to a plurality of function keys,

wherein said plurality of function keys generate a plurality of user commands to said controller through said function key interface.

11. The controller of claim 1, further comprising:

a processor for controlling said state of said switch.

12. The controller of claim 1, wherein said audio data comprises non-compressed audio data.

13. A controller for enabling a plurality of audio files to be played on a computer subsystem of a computer system if said computer system is in an inactive state, said controller comprising:

a switch having a first state and a second state, wherein said switch in said first state decouples said controller from said computer subsystem and from an audio IC coupled to said computer subsystem, wherein said audio IC is configured to play said plurality of audio files if said switch is in said first state, and wherein said switch in said second state couples said controller to said computer subsystem in response to said computer system being in said inactive state;

a drive interface configured to interface with a drive of said computer subsystem depending on a state of said switch, wherein said drive interface is configured to access compressed audio data on said drive if said switch is in said second state; and

decoder circuitry for receiving said compressed audio data and output decompressed audio data to a speaker so as to play said plurality of audio files if said switch is in said second state, wherein said speaker is selectively coupled to said audio IC and said decoder circuit according to said state of said switch.

14. The controller of claim 13, wherein said decoder circuitry comprises a buffer memory for temporarily storing said decompressed audio data.

15. The controller of claim 14, wherein said buffer memory comprises a first-in-first-out (FIFO) memory.

16. The controller of claim 13, wherein said decoder circuitry comprises a digital to analog circuit for receiving said decompressed audio data and for generating an analog audio signal.

17. The controller of claim 13, wherein said decoder circuitry comprises an interface circuit for receiving said decompressed audio data and for communicating with an external digital to analog converter.

18. A method for playing a plurality of audio files in a computer system comprising a computer subsystem, said method comprising:

decoupling an audio controller comprising a switch and a drive interface from said computer subsystem and from an audio IC coupled to said computer subsystem if said computer system is in an active state,

playing said plurality of audio files by said audio IC if said computer system is in said active state;

coupling said audio controller to said computer subsystem if said computer system is in an inactive state;

controlling access and playing of said plurality of audio files by said audio controller if said computer system is in said inactive state; and

selectively coupling said audio IC and said audio controller to a speaker according to said active state and said inactive state.

19. The method of claim 18, further comprising:

detecting if said computer system is in said active state; and

detecting if said computer system is in said inactive state.