SNLS568D March   2017  – May 2020 LMH1228

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Simplified Block Diagram
  4. 4 Revision History
  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 Clock and Data (CDR) Recovery
      6. 7.3.6 Internal Eye Opening Monitor (EOM)
      7. 7.3.7 Output Function Control
      8. 7.3.8 Output Driver Control
        1. 7.3.8.1 Line-Side Output Cable Driver (SDI_OUT1+, SDI_OUT2+)
          1. 7.3.8.1.1 Output Amplitude (VOD)
          2. 7.3.8.1.2 Output Pre-Emphasis
          3. 7.3.8.1.3 Output Slew Rate
          4. 7.3.8.1.4 Output Polarity Inversion
        2. 7.3.8.2 Host-Side 100-Ω Output Driver (OUT0±)
      9. 7.3.9 Status Indicators and Interrupts
        1. 7.3.9.1 LOCK_N (Lock Indicator)
        2. 7.3.9.2 SD_N (Signal Detect)
        3. 7.3.9.3 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 Low-Power Optimization
      3. 8.1.3 Optimized Loop Bandwidth Settings for Arria 10 FPGA Applications
    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
        1. 10.1.2.1 SDI_OUT1± and SDI_OUT2±:
        2. 10.1.2.2 IN0± and OUT0±:
      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. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Export Control Notice
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Package Option Addendum
      1. 12.1.1 Packaging Information
      2. 12.1.2 Tape and Reel Information

Package Options

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

8.1.2 Low-Power Optimization

The LMH1228 IN0 CTLE operates in either AM1 Adaptive Mode or AM0 Manual Mode. When operating in AM1, the LMH1228 uses HEO/VEO Lock Monitoring as a key parameter to achieve lock. HEO/VEO Lock Monitoring determines the CTLE boost setting that produces the best horizontal and vertical eye opening after the CTLE. Once AM1 adaptation is complete and the LMH1228 asserts CDR lock at the optimal IN0 CTLE setting, HEO/VEO Lock Monitoring is no longer required to maintain lock. Therefore, HEO/VEO Lock Monitoring can be disabled by setting CTLE/CDR Reg 0x3E[7] = 0'b after lock is declared. Disabling HEO/VEO Lock Monitoring optimizes power dissipation, reducing the overall power by approximately 25 mW.

When operating in AM0, the LMH1228 does not use HEO/VEO Lock Monitoring, because the IN0 CTLE setting is set manually by the user. In AM0, HEO/VEO Lock Monitoring can be disabled at any time.