SNAS598B July   2012  – July 2015 LM4549B

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  ADC Inputs and Outputs
      2. 8.3.2  Analog Mixing: MIX1
      3. 8.3.3  DAC Mixing and 3D Processing
      4. 8.3.4  Analog Mixing: MIX2
      5. 8.3.5  Stereo Mix
      6. 8.3.6  Stereo Outputs
      7. 8.3.7  Mono Output
      8. 8.3.8  Analog Loopthrough and Digital Loopback
      9. 8.3.9  Resets
      10. 8.3.10 Backwards Compatibility
    4. 8.4 Device Functional Modes
      1. 8.4.1 Low Power Modes
      2. 8.4.2 Test Modes
    5. 8.5 Programming
      1. 8.5.1 AC Link Serial Interface Protocol
        1. 8.5.1.1 AC Link Output Frame: SDATA_OUT, Controller Output to LM4549B Input
          1. 8.5.1.1.1 SDATA_OUT: Slot 0 - Tag Phase
          2. 8.5.1.1.2 SDATA_OUT: Slot 1 - Read/Write, Control Address
          3. 8.5.1.1.3 SDATA_OUT: Slot 2 - Control Data
          4. 8.5.1.1.4 SDATA_OUT: Slots 3 & 4 - PCM Playback Left/Right Channels
          5. 8.5.1.1.5 SDATA_OUT: Slots 5 to 12 - Reserved
        2. 8.5.1.2 AC Link Input Frame: SDATA_IN, Controller Input from LM4549B Output
          1. 8.5.1.2.1 SDATA_IN: Slot 0 - Codec/Slot Status Bits
          2. 8.5.1.2.2 SDATA_IN: Slot 1 - Status Address / Slot Request Bits
          3. 8.5.1.2.3 SDATA_IN: Slot 2 - Status Data
          4. 8.5.1.2.4 SDATA_IN: Slot 3 - PCM Record Left Channel
          5. 8.5.1.2.5 SDATA_IN: Slot 4 - PCM Record Right Channel
          6. 8.5.1.2.6 SDATA_IN: Slots 5 to 12 - Reserved
      2. 8.5.2 Multiple Codecs
        1. 8.5.2.1 Extended AC Link
        2. 8.5.2.2 Secondary Codec Register Access
          1. 8.5.2.2.1 Slot 0: TAG bits in Output Frames (Controller to Codec)
          2. 8.5.2.2.2 Extended Audio ID register (28h): Support for Multiple Codecs
    6. 8.6 Register Maps
      1. 8.6.1  Reset Register (00h)
      2. 8.6.2  Master Volume Register (02h)
      3. 8.6.3  Line Level Volume Register (04h)
      4. 8.6.4  Mono Volume Register (06h)
      5. 8.6.5  PC Beep Volume Register (0Ah)
      6. 8.6.6  Mixer Input Volume Registers (Index 0Ch - 18h)
      7. 8.6.7  Record Select Register (1Ah)
      8. 8.6.8  Record Gain Register (1Ch)
      9. 8.6.9  General Purpose Register (20h)
      10. 8.6.10 3D Control Register (22h)
      11. 8.6.11 Power-Down Control / Status Register (26h)
      12. 8.6.12 Extended Audio ID Register (28h)
      13. 8.6.13 Extended Audio Status/Control register (2Ah)
      14. 8.6.14 Sample Rate Control Registers (2Ch, 32h)
      15. 8.6.15 Vendor ID Registers (7Ch, 7Eh)
      16. 8.6.16 Reserved Registers
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
    3. 9.3 System Example
      1. 9.3.1 Improving System Performance
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
  12. 12Device and Documentation Support
    1. 12.1 Community Resources
    2. 12.2 Trademarks
    3. 12.3 Electrostatic Discharge Caution
    4. 12.4 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

5 Description (continued)

The LM4549B features the ability to connect several codecs together using the Extended AC Link configuration of one dedicated serial data signal to the Controller per codec. LM4549B systems support up to 8 simultaneous channels of streaming data on Input Frames (Codec to Controller) while Output Frames (Controller to Codec) carry 2 streams to multiple codecs. The LM4549B may also be used in systems with the Texas Instruments LM4550B to support up to 6 simultaneous channels of streaming data on Output Frames.

The AC '97 architecture separates the analog and digital functions of the PC audio system allowing both for system design flexibility and increased performance.