USB 2.0 Hub testing
The USB 2.0 Hub is covered in the USB 2.0 Spec.
The USB-IF Compliance program prohibited Full Speed
Hubs and are
only allowed if they have compound devices.
Compound devices that have no downstream
ports accessible are also considered to be a Hub.
For the USB-IF Compliance program the Device should under go the following test:
- High Speed Electrical
- Upstream device
- Downstream ports
- Full/Low Speed Signal Quality
- Full Speed upstream
- Full Speed downstream
- Low Speed downstream
- Inrush
- Drop
- Droop
- Back Voltage
- Interoperability (Goldtree)
- USBCV
- Power consumption
| USB 2.0 Hub | HS UP | HS DOWN | FS UP | FS DOWN | LS DOWN | Inrush | Drop | Droop | Back Voltage | IOP | USBCV | Power consumption | BC CDP |
High
Speed  |
Y | A | Y | A | A | Y | A | M | Y | Y | Y | Y | F |
Full
Speed  |
Y | A | A | Y | A | M | Y | Y | Y | Y | F |
Y = Always required
A = Test required to all accessible downstream ports
M = Required if there are multiple downstream ports
F = Required if battery charging is supported
When submitting for USB-IF Compliance also take care of the following:
- Check that the product complies with the USB-IF requirements of the USB-IF Compliance website
- Complete the VIF file. You can download the USB Vendor Info File Generator at www.usb.org
- Make sure that the used cables and connectors are USB-IF certified !!!
NON USB-IF certified Hub silicon
When the USB 2.0 High Speed Hub Silicon is not certified the vendor must also go through the USBHTT.
In order to run the USBHTT test you will need the Low, Full and High Speed Compliance Tes device from the USB-IF eStore
In addition of the USB-IF Compliance program it's advisable to also perform following test.
- Test the Checklist items
- Intens Interoperability test
- TDR Impedance
- Real time EYE diagram
- Testing under different temperatures conditions