SLLS505P February   2002  – February 2022 SN65HVD10 , SN65HVD11 , SN65HVD12 , SN75HVD10 , SN75HVD11 , SN75HVD12

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  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  Driver Electrical Characteristics
    6. 7.6  Receiver Electrical Characteristics
    7. 7.7  Power Dissipation Characteristics
    8. 7.8  Driver Switching Characteristics
    9. 7.9  Receiver Switching Characteristics
    10. 7.10 Dissipation Ratings
    11. 7.11 Typical Characteristics
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
    4. 9.4 Device Functional Modes
      1. 9.4.1 Low-Power Standby Mode
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
        1. 10.2.1.1 Data Rate and Bus Length
        2. 10.2.1.2 Stub Length
        3. 10.2.1.3 Bus Loading
        4. 10.2.1.4 Receiver Fail-safe
      2. 10.2.2 Detailed Design Procedure
      3. 10.2.3 Application Curve
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
    3. 12.3 Thermal Considerations
      1. 12.3.1 Thermal Characteristics of IC Packages
  13. 13Device and Documentation Support
    1. 13.1 Device Support
    2. 13.2 Related Links
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Support Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

12.1 Layout Guidelines

On-chip IEC-ESD protection is sufficient for laboratory and portable equipment, but never sufficient for EFT and surge transients occurring in industrial environments. Therefore, robust and reliable bus node design requires the use of external transient protection devices.

It is because ESD and EFT transients have a wide frequency bandwidth from approximately 3 MHz to 3 GHz, that high-frequency layout techniques must be applied during PCB design.

  1. Place the protection circuitry close to the bus connector to prevent noise transients from entering the board.
  2. Use VCC and ground planes to provide low-inductance. Note that high-frequency currents follow the path of least inductance and not the path of least impedance.
  3. Design the protection components into the direction of the signal path. Do not force the transient currents to divert from the signal path to reach the protection device.
  4. Apply 100-nF to 220-nF bypass capacitors as close as possible to the VCC pins of transceiver, UART, and controller ICs on the board.
  5. Use at least two vias for VCC and ground connections of bypass capacitors and protection devices to minimize effective via-inductance.
  6. Use 1-kΩ to 10-kΩ pull-up or pull-down resistors to enable lines to limit noise currents in these lines during transient events.
  7. Insert pulse-proof series resistors into the A and B bus lines if the TVS clamping voltage is higher than the specified maximum voltage of the transceiver bus terminals. These resistors limit the residual clamping current into the transceiver and prevent it from latching up.
  8. While pure TVS protection is sufficient for surge transients up to 1 kV, higher transients require metal-oxide varistors (MOVs) which reduce the transients to a few hundred volts of clamping voltage, and transient blocking units (TBUs) that limit transient current to less than 1 mA.