SLLSEV1C September   2017  – December 2018 THVD1510 , THVD1512 , THVD1550 , THVD1551 , THVD1552

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      THVD1510 and THVD1550 Simplified Schematic
      2.      THVD1551 Simplified Schematic
      3.      THVD1512 and THVD1552 Simplified Schematic
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
    2.     Pin Functions
    3.     Pin 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 Power Dissipation
    6. 7.6 Electrical Characteristics
    7. 7.7 Switching Characteristics
    8. 7.8 Switching Characteristics
    9. 7.9 Typical Characteristics
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagrams
    3. 9.3 Feature Description
    4. 9.4 Device Functional Modes
      1. 9.4.1 Device Functional Modes for THVD1510 and THVD1550
      2. 9.4.2 Device Functional Modes for THVD1551
      3. 9.4.3 Device Functional Modes for THVD1512 and THVD1552
  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 Failsafe
        5. 10.2.1.5 Transient Protection
      2. 10.2.2 Detailed Design Procedure
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
    2. 13.2 Third-Party Products Disclaimer
    3. 13.3 Related Links
    4. 13.4 Receiving Notification of Documentation Updates
    5. 13.5 Community Resources
    6. 13.6 Trademarks
    7. 13.7 Electrostatic Discharge Caution
    8. 13.8 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • D|14
  • DGS|10
Thermal pad, mechanical data (Package|Pins)
Orderable Information

10.2.1.4 Receiver Failsafe

The differential receivers of the THVD15xx family are failsafe to invalid bus states caused by the following:

  • Open bus conditions, such as a disconnected connector
  • Shorted bus conditions, such as cable damage shorting the twisted-pair together
  • Idle bus conditions that occur when no driver on the bus is actively driving

In any of these cases, the differential receiver will output a failsafe logic high state so that the output of the receiver is not indeterminate.

Receiver failsafe is accomplished by offsetting the receiver thresholds such that the input indeterminate range does not include zero volts differential. In order to comply with the RS-422 and RS-485 standards, the receiver output must output a high when the differential input VID is more positive than 200 mV, and must output a low when VID is more negative than –200 mV. The receiver parameters which determine the failsafe performance are VTH+, VTH–, and VHYS (the separation between VTH+ and VTH–). As shown in the Electrical Characteristics table, differential signals more negative than –200 mV will always cause a low receiver output, and differential signals more positive than 200 mV will always cause a high receiver output.

When the differential input signal is close to zero, it is still above the VTH+ threshold, and the receiver output will be high. Only when the differential input is more than VHYS below VTH+ will the receiver output transition to a low state. Therefore, the noise immunity of the receiver inputs during a bus fault conditions includes the receiver hysteresis value, Vhys, as well as the value of VTH+.