The USB interface to the host computer system is referred to as the Host Controller. The Host Controller may be implemented in a combination of hardware, firmware or software. A ‘root hub’ is integrated within the host system to provide one or more attachment points. The USB connects USB devices with the USB host. The USB physical interconnection is a tiered star topology. A ‘hub’ is at the center of each star. Each wire segment is a point-to-point connection between the ‘host’ and a ‘hub’ or ‘function,’ or a ‘hub’ connected to another ‘hub’ or ‘function.’
Acceptance Criteria, Test Methods and Test Procedures (USB Technology)
For a USB connector or fabricated cable assembly product to be listed on the USB-IF Integrators List, the manufacturer must show satisfactory completion of all qualification tests specified in the most current version of the USB Specification and the USB-IF Cable & Connector Class Document. Cable assemblies must implement certified USB connectors in order to submit the cable assembly for certification testing.
IMPORTANT NOTICE: Fabricated USB connectors and cable assemblies must successfully pass all inspection procedures and compliance testing at the intervals shown in Table 4-3, Primary Qualification Approval Testing, and Table 4-4, Sustaining Qualification Approval Testing, of the most current version of the USB-IF Cable & Connector Class Document before listing on the USB-IF Integrators List will be granted.
Integrators List (IL) (USB Technology)
USB-IF maintains a current listing of ‘IL manufacturers and/or fabricators’ who have been authorized to use the trademarked ‘USB logo’ in conjunction with or on their connector and/or fabricated cable assembly products. The USB-IF’s listing of approved manufacturers is periodically updated and is available to all USB-IF member companies.
Connector and Cable Assembly Physical Certification
In case of conflict between the requirements of this document and the USB Specification, the most current revision of the USB Specification & applicable USB Supplements shall take precedence. Unless otherwise specified, all tests shall be performed at the following standard test conditions.
Table 4-1 Standard Test Conditions
|Temperature||15O C to 35O C|
|Air Pressure||86 to 106 KPa|
|Relative Humidity||25% to 85%|
Cable Assemblies (USB Technology)
The cable construction for standard detachable USB cable assemblies is to be visually verified. Cable construction must contain a braided outer shield and a metallic inner shield. A drain wire of 28 AWG must be in contact with both shields. Cables must contain two data-lines of 28 AWG, and a power pair of 28 AWG to 20 AWG. Power pairs smaller than 28 AWG are prohibited. The laboratory conducting the compliance testing is required to visually verify the construction of the cable.