SLLS849E april   2008  – august 2023 AM26LV32E

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Switching Characteristics
    7. 6.7 Typical Characteristics
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 ±7-V Common-Mode Range With ±200-mV Sensitivity
      2. 8.3.2 Input Fail-Safe Circuitry
      3. 8.3.3 Active-High and Active-Low
    4. 8.4 Device Functional Modes
      1. 8.4.1 Enable and Disable
  10. 9 Application Information Disclaimer
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curve
  11. 10Power Supply Recommendations
  12. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  13. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  14. 13Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.2 Input Fail-Safe Circuitry

RS-485 specifies that the receiver output state should be logic high for differential input voltages of VAB ≥ +200 mV and logic low for VAB ≤ –200 mV. For input voltages in between these limits, a receiver’s output state is not defined and can randomly assume high or low. Removing the uncertainty of random output states, modern transceiver designs include internal biasing circuits that put the receiver output into a defined state (typically high) in the absence of a valid input signal. A loss of input signal can be caused by:

  • an open circuit caused by a wire break or the unintentional disconnection of a transceiver from the bus
  • a short circuit due to an insulation fault, connecting both conductors of a differential pair to one another
  • an idle bus when none of the bus transceivers are active.
An open circuit caused by a wire break or the unintentional disconnection of a transceiver from the bus. The AM26LV32E has an internal circuit that ensures functionality during an open failure.