SNLS624 September   2018 DSLVDS1048

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1. 3.1 Application Diagram
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions
  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
  7. Parameter Measurement Information
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Fail-Safe Feature
    4. 8.4 Device Functional Modes
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Probing LVDS Transmission Lines
        2. 9.2.2.2 Threshold
      3. 9.2.3 Application Curve
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Power Decoupling Recommendations
      2. 11.1.2 Differential Traces
      3. 11.1.3 Termination
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

Threshold

The LVDS Standard (ANSI/TIA/EIA-644) specifies a maximum threshold of ±100 mV for the LVDS receiver. The DSLVDS1048 supports an enhanced threshold region of −100 mV to 0 V. This is useful for fail-safe biasing. The threshold region is shown in the Voltage Transfer Curve (VTC) in Figure 20. The typical DSLVDS1048 LVDS receiver switches at about −35 mV.

NOTE

With VID = 0 V, the output is in a HIGH state. With an external fail-safe bias of +25 mV applied, the typical differential noise margin is now the difference from the switch point to the bias point.

In the following example, this would be 60 mV of Differential Noise Margin (+25 mV − (−35 mV)). With the enhanced threshold region of −100 mV to 0 V, this small external fail-safe biasing of +25 mV (with respect to
0 V) gives a DNM of a comfortable 60 mV. With the standard threshold region of ±100 mV, the external fail-safe biasing would need to be +25 mV with respect to +100 mV or +125 mV, giving a DNM of 160 mV which is stronger fail-safe biasing than is necessary for the DSLVDS1048. If more DNM is required, then a stronger fail-safe bias point can be set by changing resistor values.

DSLVDS1048 10088830.pngFigure 20. VTC of the DSLVDS1048 LVDS Receiver