Description

The USB 2.0 is a 4 core cable.(VCC,GND,D+,D-)

The USB Hub system consist of below blocks

  • Upstream Port (connection with the host PC)
  • Downstream port (connection with the peripherals)
  • Main USB HUB controller (manages the communication between peripheral devices and the computer system)
  • Overcurrent protection IC (Protect the downstream port from short circuit and overcurrnet).
  • ESD protection for downstream and upstream port (To protect the circuit from ESD)

The USB HUB controller IC has different variants with 2,3,4 and 8 downstream ports. Below are the list of USB2.0 Hub ICs that we used

  • USB2512B
    • 2 Downstream Port
    • 36 pin QFN Package
  • USB2514B
    • 4 Downstream Port
    • 36 pin QFN Package
  • USB2640
    • 2 Downstream Port
    • QFN Package
    • Flash memory card support
  • FE1.1
    • 4 Downstream port

PCB Layout

A PCB layout design guideline has to be followed while designing the high speed pcb to maintain signal integrity and avoid EMC issues.

PCB Details

  • 4 Layer Impedance controlled PCB.
  • USB2.0 D+/D- differntial pair routing
  • D+/D- trace impedance : 90 Ohm

USB Hub used on PCB