SNLU346 May   2024 TUSB2E221

 

  1.   1
  2.   Description
  3.   Features
  4.   Applications
  5.   5
  6. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
  7. 2Hardware
    1. 2.1 Getting Started
    2. 2.2 EVM Configuration
      1. 2.2.1 Power Modes
        1. 2.2.1.1 Self-Powered Configuration
        2. 2.2.1.2 Bus-powered Configuration
        3. 2.2.1.3 External Power
      2. 2.2.2 Functional Modes
        1. 2.2.2.1 I2C-Enabled Repeater Mode
        2. 2.2.2.2 GPIO Repeater Mode
        3. 2.2.2.3 UART Mode
      3. 2.2.3 I/O and Interrupts
  8. 3Hardware Design Files
    1. 3.1 Schematic
    2. 3.2 Board Layout
    3. 3.3 Bill of Materials
  9. 4Additional Information
    1. 4.1 Trademarks

3.2 Board Layout

The TUSB2E221EVM was laid out with the following considerations:

  • USB 2.0 signals impedance controlled 90Ω differential ± 5%.
  • eUSB2 signals impedance controlled 45Ω signal ended ± 5%.
  • USB 2.0 and eUSB2 signal pairs routed with matched trace lengths and minimal vias.
  • All other signals to be impedance controlled 45Ω ± 10% or 50Ω ± 10%.

General information about the PCB is provided below:

  • Finished board thickness: .062 ± 10% – necessary for socket
  • Copper weight: 1oz start internal, 1/2 oz start external
  • Laminate material: FR4 Polyclad 370 or equivalent

A four layer stack-up was used for the TUSB2E221EVM.

Drill notes on board stack up to account for the small BGA breakout:

  1. 1. L1 – L2 (laser drill) used for small pitch BGA break out.
  2. 2. L2 – L3 (mechanical drill) completes the small pitch BGA breakout.
  3. 3. L3 – L4 (laser drill) for VPP.
TUSB2E221EVM TUSB2E221EVM PCB Top LayerFigure 3-2 TUSB2E221EVM PCB Top Layer
TUSB2E221EVM TUSB2E221EVM PCB Layer 3 (Power Plane)Figure 3-4 TUSB2E221EVM PCB Layer 3 (Power Plane)
TUSB2E221EVM TUSB2E221EVM PCB Layer 2 (Ground Plane)Figure 3-3 TUSB2E221EVM PCB Layer 2 (Ground Plane)
TUSB2E221EVM TUSB2E221EVM Layer 4 (Bottom)Figure 3-5 TUSB2E221EVM Layer 4 (Bottom)