SGLS423A February   2025  – December 2025 SN55LVRA4-SEP

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Switching Characteristics
    7. 5.7 Typical Characteristics
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Receiver Output States
      2. 7.3.2 General Purpose Comparator
      3. 7.3.3 Common-Mode Range vs Supply Voltage
    4. 7.4 Equivalent Input and Output Schematic Diagrams
    5. 7.5 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Detailed Design Procedure
      2. 8.2.2 Design Requirements
      3. 8.2.3 Application Performance Plots
      4. 8.2.4 Cold Sparing
    3. 8.3 Active Failsafe Feature
    4. 8.4 ECL/PECL-to-LVTTL Conversion with TI's LVDS Receiver
    5. 8.5 Test Conditions
    6. 8.6 Equipment
  10. 9 Power Supply Recommendations
    1. 9.1 Supply Bypass Capacitance
  11. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Microstrip vs. Stripline Topologies
      2. 10.1.2 Dielectric Type and Board Construction
      3. 10.1.3 Recommended Stack Layout
      4. 10.1.4 Separation Between Traces
      5. 10.1.5 Crosstalk and Ground Bounce Minimization
    2. 10.2 Layout Example
  12. 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 Glossary
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information

10.1.2 Dielectric Type and Board Construction

The speeds at which signals travel across the board dictates the choice of dielectric. FR-4, or equivalent, usually provides adequate performance for use with LVDS signals. If rise or fall times of TTL/CMOS signals are less than 500ps, empirical results indicate that a material with a dielectric constant near 3.4, such as Rogers™ 4350 or Nelco N4000-13 is better suited. Once the designer chooses the dielectric, there are several parameters pertaining to the board construction that can affect performance. The following set of guidelines were developed experimentally through several designs involving LVDS devices:

  • Copper weight: 15g or 1/2oz start, plated to 30g or 1oz
  • All exposed circuitry should be solder-plated (60/40) to 7.62μm or 0.0003in (minimum).
  • Copper plating should be 25.4μm or 0.001in (minimum) in plated-through-holes.
  • Solder mask over bare copper with solder hot-air leveling