SNLS545E March   2017  – July 2022 LMH1297

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 Recommended SMBus Interface Timing Specifications
    7. 7.7 Serial Parallel Interface (SPI) Timing Specifications
    8. 7.8 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  4-Level Input Pins and Thresholds
      2. 8.3.2  Equalizer (EQ) and Cable Driver (CD) Mode Control
        1. 8.3.2.1 EQ/CD_SEL Control
        2. 8.3.2.2 OUT0_SEL and SDI_OUT_SEL Control
      3. 8.3.3  Input Carrier Detect
      4. 8.3.4  –6-dB Splitter Mode Launch Amplitude for SDI_IO+ (EQ Mode Only)
      5. 8.3.5  Continuous Time Linear Equalizer (CTLE)
        1. 8.3.5.1 Line-Side Adaptive Cable Equalizer (SDI_IO+ in EQ mode)
        2. 8.3.5.2 Host-Side Adaptive PCB Trace Equalizer (IN0± in CD Mode)
      6. 8.3.6  Clock and Data (CDR) Recovery
      7. 8.3.7  Internal Eye Opening Monitor (EOM)
      8. 8.3.8  Output Function Control
      9. 8.3.9  Output Driver Control
        1. 8.3.9.1 Line-Side Output Cable Driver (SDI_IO+ in CD mode, SDI_OUT+ in EQ or CD mode)
          1. 8.3.9.1.1 Output Amplitude (VOD)
          2. 8.3.9.1.2 Output Pre-Emphasis
          3. 8.3.9.1.3 Output Slew Rate
          4. 8.3.9.1.4 Output Polarity Inversion
        2. 8.3.9.2 Host-Side 100-Ω Output Driver (OUT0± in EQ or CD mode)
      10. 8.3.10 Status Indicators and Interrupts
        1. 8.3.10.1 LOCK_N (Lock Indicator)
        2. 8.3.10.2 CD_N (Carrier Detect)
        3. 8.3.10.3 INT_N (Interrupt)
      11. 8.3.11 Additional Programmability
        1. 8.3.11.1 Cable EQ Index (CEI)
        2. 8.3.11.2 Digital MUTEREF
    4. 8.4 Device Functional Modes
      1. 8.4.1 System Management Bus (SMBus) Mode
        1. 8.4.1.1 SMBus Read and Write Transaction
          1. 8.4.1.1.1 SMBus Write Operation Format
          2. 8.4.1.1.2 SMBus Read Operation Format
      2. 8.4.2 Serial Peripheral Interface (SPI) Mode
        1. 8.4.2.1 SPI Read and Write Transactions
        2. 8.4.2.2 SPI Write Transaction Format
        3. 8.4.2.3 SPI Read Transaction Format
        4. 8.4.2.4 SPI Daisy Chain
    5. 8.5 Register Maps
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 SMPTE Requirements and Specifications
      2. 9.1.2 Low-Power Optimization in CD Mode
      3. 9.1.3 Optimized Loop Bandwidth Settings for Arria 10 FPGA Applications
    2. 9.2 Typical Applications
      1. 9.2.1 Bidirectional I/O
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Cable Equalizer With Loop-Through
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Board Stack-Up and Ground References
      2. 11.1.2 High-Speed PCB Trace Routing and Coupling
        1. 11.1.2.1 SDI_IO± and SDI_OUT±:
        2. 11.1.2.2 IN0± and OUT0±:
      3. 11.1.3 Anti-Pads
      4. 11.1.4 BNC Connector Layout and Routing
      5. 11.1.5 Power Supply and Ground Connections
      6. 11.1.6 Footprint Recommendations
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Support Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.2.1.1 Design Requirements

For general LMH1297 design requirements, reference the guidelines in Table 9-1.

For bidirectional I/O application-specific requirements, reference the guidelines in Table 9-2.

Table 9-1 LMH1297 General Design Requirements
DESIGN PARAMETERREQUIREMENTS
SDI_IO+, SDI_OUT+ AC-coupling capacitors4.7-μF capacitors recommended
SDI_IO–, SDI_OUT– AC-coupling capacitors4.7-μF capacitors recommended, AC terminated with 75 Ω to VSS.
IN0± and OUT0± AC-coupling capacitors4.7-μF capacitors recommended
Input and Output TerminationsInput and output terminations provided internally. Do not add external terminations.
DC power supply decoupling capacitors10-μF and 1-μF bulk capacitors; place close to each device.
0.1-μF capacitor; place close to each supply pin.
VDD_LDO decoupling capacitors1-μF and 0.1-μF capacitors; place as close as possible to the device VDD_LDO pin.
MODE_SEL PinSPI: Leave MODE_SEL unconnected (Level F)
SMBus: Connect 1 kΩ to VSS (Level L)
Input Reclocked Data Rate (SDI_IO in EQ mode or IN0 in CD mode)11.88 Gbps, 5.94 Gbps, 2.97 Gbps, 1.485 Gbps, or Divide-by-1.001 sub-rates and 270 Mbps.
For all other input data rates, the reclocker is automatically bypassed.
Table 9-2 LMH1297 Bidirectional I/O Requirements
DESIGN PARAMETERREQUIREMENTS
EQ/CD_SEL Pin1 kΩ to VSS (Level L) when SDI_IO is used as a cable EQ input
1 kΩ to VIN (Level H) when SDI_IO is used as a cable driver output
OUT0_SEL Pin1 kΩ to VSS (Level L) to enable OUT0 for monitoring purposes
1 kΩ to VIN (Level H) to disable OUT0 (available only in CD mode)
SDI_OUT_SEL Pin1 kΩ to VSS (Level L) to enable cable loop-through (EQ mode) or secondary cable output (CD mode)
1 kΩ to VIN (Level H) to disable cable loop-through (EQ mode) or secondary cable output (CD mode)