SLLSFL2A April   2022  – May 2024 TUSB1142

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1  Absolute Maximum Ratings
    2. 5.2  ESD Ratings
    3. 5.3  Recommended Operating Conditions
    4. 5.4  Thermal Information
    5. 5.5  Power Supply Characteristics
    6. 5.6  Control I/O DC Electrical Characteristics
    7. 5.7  USB Electrical Characteristics
    8. 5.8  Timing Requirements
    9. 5.9  Switching Characteristics
    10. 5.10 Typical Characteristics
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 4-Level Inputs
      2. 7.3.2 USB Receiver Linear Equalization
        1. 7.3.2.1 Linear EQ Configuration
        2. 7.3.2.2 Full Adaptive Equalization
        3. 7.3.2.3 Fast Adaptive Equalization
      3. 7.3.3 USB Transmitter
        1. 7.3.3.1 Linearity VOD
        2. 7.3.3.2 Limited VOD
        3. 7.3.3.3 Transmit Equalization (Limited Redriver Mode Only)
      4. 7.3.4 USB 3.2 2:1 MUX Description
      5. 7.3.5 USB Polarity Inversion
      6. 7.3.6 Receiver Detect Control
    4. 7.4 Device Functional Modes
      1. 7.4.1 MODE Pin
      2. 7.4.2 Rx EQ Configuration in Pin-Strap Mode
      3. 7.4.3 USB 3.2 Power States
      4. 7.4.4 Disabling U1 and U2
    5. 7.5 Programming
      1. 7.5.1 Pseudocode Examples
        1. 7.5.1.1 Fixed EQ with Linear Redriver Mode
        2. 7.5.1.2 Fixed EQ with Limited Redriver Mode
        3. 7.5.1.3 Fast AEQ with Linear Redriver Mode
        4. 7.5.1.4 Fast AEQ with Limited Redriver Mode
        5. 7.5.1.5 Full AEQ with Linear Redriver Mode
        6. 7.5.1.6 Full AEQ with Limited Redriver Mode
      2. 7.5.2 TUSB1142 I2C Address Options
      3. 7.5.3 TUSB1142 I2C Target Behavior
    6. 7.6 Register Map
      1. 7.6.1 TUSB1142 Registers
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 USB SSTX Receiver Configuration
        2. 8.2.2.2 USB CRX1/2 Receiver Configuration
          1. 8.2.2.2.1 Fixed Equalization
          2. 8.2.2.2.2 Full Adaptive Equalization
          3. 8.2.2.2.3 Fast Adaptive Equalization
        3. 8.2.2.3 ESD Protection
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

8.2.2.1 USB SSTX Receiver Configuration

Configuring the TUSB1142 involves understanding the insertion loss (SDD21) of the pre-channel (XAB). The TUSB1142's SSEQ[1:0] pins if pin-strap mode, or if I2C mode, SSEQ1_SEL registers should be set to the level of the pre-channel insertion loss at 5 GHz. A good rule for FR4 trace insertion loss at 5 GHz is ≈-1 dB per inch. Using this rule, if the pre-channel for USB (XAB) is 8-inches, the TUSB1142 SSEQ should be programmed to -8 dB.