Why Should I Buy the Keysight USB 2.0 A/B Fixture Kit, E2649B, Instead of the USB Implementers Forum's Fixtures?
Why Should I Buy the Keysight USB 2.0 A/B Fixture Kit, E2649B, Instead of the USB Implementers Forum's Fixtures?
Industry Test Standards InformationJuly 11, 20262 min read
Summary
You may need both.
Description
The USB-IF requires the use of its own USB 2.0 fixtures, the USB2SIGQUAL kit, with coaxial cables, for High Speed (480 Mb/s) Signal Quality compliance testing. Why should I buy the Keysight USB 2.0 fixture kit, E2649B?
Four reasons the Keysight E2649B USB 2.0 HS fixture kit may be needed:
All of the tests mentioned require probing access which the USB-IF Signal Quality fixtures do not provide. Even with solder-in probes, some of the tests require passive probes. The USB-IF fixtures are not suitable for probing.
Many of the of the host tests require the ability to switch in an ideal termination and attach a known good High Speed-capable device. While the USB-IF host fixture can be terminated into the ideal load by placing 50 Ω loads on coaxial outputs, there is no way to attach a known good High Speed-capable device
The device receiver sensitivity test requires the ability to switch out the host and switch in a signal generator. The USB-IF fixtures do not provide this. The Keysight E2649B includes this capability on a separate fixture.
The Host Disconnect test requires a separate fixture that simulates a device disconnecting from a host. The E2649B kit includes such a fixture.
If the only tests you care about are the high speed Signal Quality tests, then the USB-IF fixture kit is all that is needed. Please note that the Keysight Device and Host Signal Quality test fixture are also available as E2666B and E2667B, respectively. The Device Receiver Sensitivity and Host Disconnect fixtures are only available as part of the E2649B kit.
