SLLSFQ8 January   2024 THVD9491-SEP

ADVANCE INFORMATION  

  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 ESD Ratings [IEC]
    4. 5.4 Recommended Operating Conditions
    5. 5.5 Thermal Information
    6. 5.6 Power Dissipation
    7. 5.7 Electrical Characteristics
    8. 5.8 Switching Characteristics: 20Mbps
    9. 5.9 Switching Characteristics: 50Mbps
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagrams
    3. 7.3 Feature Description
      1. 7.3.1 ±70-V Fault Protection
      2. 7.3.2 Integrated IEC ESD and EFT Protection
      3. 7.3.3 Driver Overvoltage and Overcurrent Protection
      4. 7.3.4 Enhanced Receiver Noise Immunity
      5. 7.3.5 Receiver Fail-Safe Operation
      6. 7.3.6 Low-Power Shutdown Mode
    4. 7.4 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
        1. 8.2.1.1 Data Rate and Bus Length
        2. 8.2.1.2 Stub Length
        3. 8.2.1.3 Bus Loading
        4. 8.2.1.4 Transient Protection
      2. 8.2.2 Detailed Design Procedure
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information
    1. 11.1 Tape and Reel Information
    2. 11.2 Mechanical Data

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • D|14
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.2.1.1 Data Rate and Bus Length

There is an inverse relationship between data rate and cable length, which means the higher the data rate, the short the cable length; and conversely, the lower the data rate, the longer the cable length. While most RS-485 systems use data rates between 10kbps and 100kbps, some applications require data rates up to 250kbps at distances of 4000 feet and longer. Longer distances are possible by allowing for small signal jitter of up to 5 or 10%.

GUID-461EA8CA-E469-43C2-B46C-B9A6329A464D-low.gifFigure 8-2 Cable Length vs Data Rate Characteristic

Even higher data rates are achievable (up to 50Mbps ) in cases where the interconnect is short enough (or has suitably low attenuation at signal frequencies) to not degrade the data.