SLDS120H March   2000  – March 2022 TFP401 , TFP401A

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings (1)
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 DC Digital I/O Electrical Characteristics
    6. 7.6 DC Electrical Characteristics
    7. 7.7 AC Electrical Characteristics
    8. 7.8 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
      1. 9.3.1 TMDS Pixel Data and Control Signal Encoding
      2. 9.3.2 TFP401/401A Clocking and Data Synchronization
      3. 9.3.3 TFP401/401A TMDS Input Levels and Input Impedance Matching
      4. 9.3.4 TFP401A Incorporates HSYNC Jitter Immunity
    4. 9.4 Device Functional Modes
      1. 9.4.1 TFP401/401A Modes of Operation
      2. 9.4.2 TFP401/401A Output Driver Configurations
        1. 9.4.2.1 Output Driver Power Down
        2. 9.4.2.2 Drive Strength
        3. 9.4.2.3 Time-Staggered Pixel Output
        4. 9.4.2.4 Power Management
        5. 9.4.2.5 Sync Detect
  10. 10Applications and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Data and Control Signals
        2. 10.2.2.2 Configuration Options
        3. 10.2.2.3 Power Supplies Decoupling
      3. 10.2.3 Application Curve
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 Layer Stack
      2. 12.1.2 Routing High-Speed Differential Signal Traces (RxC–, RxC+, Rx0–, Rx0+, Rx1–, Rx1+, Rx2–, Rx2+)
      3. 12.1.3 DVI Connector
    2. 12.2 Layout Example
    3. 12.3 TI PowerPAD 100-TQFP Package
  13. 13Device and Documentation Support
    1. 13.1 Receiving Notification of Documentation Updates
    2. 13.2 Support Resources
    3. 13.3 Trademarks
    4. 13.4 Electrostatic Discharge Caution
    5. 13.5 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

9.3.3 TFP401/401A TMDS Input Levels and Input Impedance Matching

The TMDS inputs to the TFP401/401A receiver have a fixed single-ended termination to AVDD. The TFP401/401A is internally optimized using a laser trim process to precisely fix the impedance at 50 Ω. The device functions normally with or without a resistor on the EXT_RES pin, so it remains drop-in compatible with current sockets. The fixed impedance eliminates the need for an external resistor while providing optimum impedance matching to standard 50-Ω DVI cables.

Figure 9-1 shows a conceptual schematic of a DVI transmitter and TFP401/401A receiver connection. A transmitter drives the twisted-pair cable via a current source, usually achieved with an open-drain type output driver. The internal resistor, which is matched to the cable impedance at the TFP401/401A input, provides a pullup to AVDD. Naturally, when the transmitter is disconnected and the TFP401/401A DVI inputs are left unconnected, the TFP401/401A receiver inputs pull up to AVDD. The single-ended differential signal and full-differential signal is shown in Figure 9-2. The TFP401/401A is designed to respond to differential signal swings ranging from 150 mV to 1.56 V with common-mode voltages ranging from (AVDD – 300 mV) to (AVDD – 37 mV).

GUID-2E8EB0D4-309A-41FC-8D28-F3ADFBC80087-low.gifFigure 9-1 TMDS Differential Input and Transmitter Connection
GUID-1D4E0449-22FE-410E-8E1B-BB4F494C9EF4-low.gifFigure 9-2 TMDS Inputs