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Data sheet:

USB-Isolator Industry, 4kV

Galvanic isolation for USB devices

The USB Isolator 33204 galvanically isolates Low-Speed and Full-Speed connections from the USB host and protects the background hardware.



  • 1 x USB socket, type A
    • Downstream port
  • 1 x USB plug, type B
    • Upstream port
  • Galvanic isolation between the ports
    • Isolation voltage min. 4kV DC

Management and connectivity:

  • Multi-stage filtered output voltage allows low-current galvanic decoupling of USB audio equipment
  • Supports low-speed and full-speed USB devices
    • Full Speed (12 MBit/s), Low Speed (1,5 MBit/s)
  • No additional software drivers necessary
  • Housing suitable for installation on top hat rails
  • Solution integrated into USB cable for plug-in

Power supply:

  • Supply voltage for Isolator and terminal device provided by USB
    • Optional external voltage supply on the upstream side. This option allows connecting of power-hungry USB devices with a load current of up to 1A without affecting the isolation voltage

Standards & more

  • Conforms to standards both in office and industrial environments:
    • High noise resistance per EN 61000-6-2
    • Low noise emission per EN 55032:2015 + A1 Cl. B, EN 61000-3-2 & EN 61000-3-3
  • 5 year guarantee

Worth knowing

USB interface:

USB interfaces in stationary computers unfortunately have the basic drawback of having no galvanic isolation for the signal lines.

In many applications in the consumer world this limitation is irrelevant, since the USB devices connected to the PC are generally supplied through the bus and do not have any reference to a second ground or to the ground conductor.

In the areas of measurement reading, process control or for example medical technology, galvanic isolation of the connected devices is mandatory in order to prevent ground loops on the USB line.

To this end W&T offers a family of USB isolators which differ in their mechanical configuration and in their supply voltage and amount of isolation voltage.

The output voltage from the 4kV Isolator is routed on the galvanically isolated side through a multi-stage L-C filter. The filtered output voltage means the Isolator is also ideal for isolating high-quality USB audio equipment.

Technical data

Connections and displays:

  • USB Port 1:
    • Upstream connection
    • Type B female
  • USB Port 2:
    • Downstream connection
    • Type A - female
  • Galvanic isolation:
    • Isolation voltage min. 4kV DC
    • (both for power from USB and for external supply)
  • Supply voltage:
    • +5V DC
  • Air and leakage paths:
    • > 8mm
  • Max. output current:
    • with USB supply typ. 300mA
    • with included power supply typ. 500mA
    • with corresponding power supply max. 1000mA
  • Current consumption:
    • typ. 200mA @5V DC
  • Displays:
    • 2x LED Full Speed
    • 2x LED Power
  • Supply connection:
    • 5V - jack connector-female

Housing and other data:

  • Enclosure:
    • Plastic housing for top hat rail installation
    • 105 x 45 x 75mm (L x W x H)
  • Enclosure rating:
    • IP20
  • Enclosure rating:
    • IP20
  • Weight:
    • approx. 200g
  • Ambient temperature:
    • Isolator:
    • Storage: -40..+70°C
    • Operating: 0..+70°C

    • Power supply:
    • Storage: -40..+70°C
    • Operating: 0..+40°C
  • Permissible relative humidity:
    • 5..90% relative humidity, non-condensing
  • Scope of delivery:
    • USB-Isolator Industry, 4kV
    • USB cable USB-A / USB-B
    • USB power supply 5V / 0.7A (only with Euro plug)
    • Power cable USB-A / barrel connector

* Our offering is intended only for commercial users. We will be happy to refer private end customers to trading partners through whom our products can be purchased.