SLLSEH3C July   2013  – January 2018 SN65HVD888

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings: JEDEC Specifications
    3. 6.3 ESD Ratings: IEC Specifications
    4. 6.4 Recommended Operating Conditions
    5. 6.5 Thermal Information
    6. 6.6 Electrical Characteristics
    7. 6.7 Power Dissipation Characteristics
    8. 6.8 Switching Characteristics
    9. 6.9 Typical Characteristics
  7. 7 Parameter Measurement information
    1. 7.1 Driver
    2. 7.2 Receiver
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Low-Power Standby Mode
      2. 8.3.2 Bus Polarity Correction
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Device Configuration
      2. 9.1.2 Bus Design
      3. 9.1.3 Cable Length Versus Data Rate
      4. 9.1.4 Stub Length
      5. 9.1.5 3- to 5-V Interface
      6. 9.1.6 Noise Immunity
      7. 9.1.7 Transient Protection
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curve
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Design and Layout Considerations For Transient Protection
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Community 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

11 Layout

11.1 Layout Guidelines

11.1.1 Design and Layout Considerations For Transient Protection

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

In order for PCB design to be successful, begin with the design of the protection circuit in mind.

  1. Place the protection circuitry close to the bus connector to prevent noise transients from penetrating your 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 transients currents to divert from the signal path to reach the protection device.
  4. Apply 100- to 220-nF bypass capacitors as close as possible to the VCC-pins of transceiver, UART, 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- to 10-k pullup or pulldown resistors for enable lines to limit noise currents in theses lines during transient events.
  7. Insert pulse-proof 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.
    • 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 some 200 mA.

11.2 Layout Example

SN65HVD888 layout_example_1.gif Figure 26. SN65HVD888 Layout Example