ZHCSKE0B March   2017  – October 2019 LMH1208

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
  3. 3 说明
    1.     简化方框图
  4. 4 修订历史记录
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Recommended SMBus Interface Timing Specifications
    7. 6.7 Serial Parallel Interface (SPI) Timing Specifications
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 4-Level Input Pins and Thresholds
      2. 7.3.2 OUT0_SEL and SDI_OUT2_SEL Control
      3. 7.3.3 Input Signal Detect
      4. 7.3.4 Continuous Time Linear Equalizer (CTLE)
      5. 7.3.5 Output Driver Control
        1. 7.3.5.1 Line-Side Output Cable Driver (SDI_OUT1+, SDI_OUT2+)
          1. 7.3.5.1.1 Output Amplitude (VOD)
          2. 7.3.5.1.2 Output Pre-Emphasis
          3. 7.3.5.1.3 Output Slew Rate
          4. 7.3.5.1.4 Output Polarity Inversion
        2. 7.3.5.2 Host-Side 100-Ω Output Driver (OUT0±)
      6. 7.3.6 Status Indicators and Interrupts
        1. 7.3.6.1 SD_N (Signal Detect)
        2. 7.3.6.2 INT_N (Interrupt)
    4. 7.4 Device Functional Modes
      1. 7.4.1 System Management Bus (SMBus) Mode
        1. 7.4.1.1 SMBus Read and Write Transaction
          1. 7.4.1.1.1 SMBus Write Operation Format
          2. 7.4.1.1.2 SMBus Read Operation Format
      2. 7.4.2 Serial Peripheral Interface (SPI) Mode
        1. 7.4.2.1 SPI Read and Write Transactions
        2. 7.4.2.2 SPI Write Transaction Format
        3. 7.4.2.3 SPI Read Transaction Format
        4. 7.4.2.4 SPI Daisy Chain
    5. 7.5 Register Maps
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 SMPTE Requirements and Specifications
      2. 8.1.2 LMH1208 and LMH1228 Compatibility
    2. 8.2 Typical Applications
      1. 8.2.1 Dual Cable Driver
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Distribution Amplifier
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Board Stack-Up and Ground References
      2. 10.1.2 High-Speed PCB Trace Routing and Coupling
      3. 10.1.3 Anti-Pads
      4. 10.1.4 BNC Connector Layout and Routing
      5. 10.1.5 Power Supply and Ground Connections
      6. 10.1.6 Footprint Recommendations
    2. 10.2 Layout Example
  11. 11器件和文档支持
    1. 11.1 文档支持
      1. 11.1.1 相关文档
    2. 11.2 接收文档更新通知
    3. 11.3 社区资源
    4. 11.4 商标
    5. 11.5 静电放电警告
    6. 11.6 出口管制提示
    7. 11.7 Glossary
  12. 12机械、封装和可订购信息
    1. 12.1 Package Option Addendum
      1. 12.1.1 Packaging Information
      2. 12.1.2 Tape and Reel Information

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息

8.1.1 SMPTE Requirements and Specifications

SMPTE specifies several key requirements for the Serial Digital Interface to transport digital video over coaxial cables. Such requirements include return loss, AC coupling, and data rate dependency with rise and fall times.

  1. Return Loss: This specification details how closely the port resembles 75-Ω impedance across a specified frequency band. The LMH1208 features a built-in 75-Ω return-loss network on SDI_OUT1 and SDI_OUT2 to minimize parasitics and improve overall signal integrity.
  2. AC Coupling: AC-coupling capacitors are required for transporting uncompressed serial data streams with heavy low-frequency content. The use of 4.7-μF, AC-coupling capacitors is recommended to avoid low-frequency DC wander.
  3. Rise/Fall Time: Output 75-Ω signals are required to meet certain rise and fall timing depending on the data rate. This improves the eye opening observed for the receiving device. The LMH1208 SDI_OUT1 and SDI_OUT2 cable drivers feature programmable edge rate adjustment to meet SMPTE rise and fall time requirements.

TI recommends placing the LMH1208 as close as possible to the 75-Ω BNC ports to meet SMPTE specifications.