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At work I was told to look for a USB 3.0 transceiver that interfaces to ULPI. I'm not able to find transceivers which fit this description. Is there some other "lingo", or feature I should be looking for?

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  • \$\begingroup\$ Really ? eetimes.com/document.asp?doc_id=1201028 \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jun 28 '18 at 22:05
  • \$\begingroup\$ From a quick google, ULPI seems to be 1. Specific to USB 2.0; and, 2. Possibly dead as a standard (maybe available as an on-chip IP block from some vendors). \$\endgroup\$ – The Photon Jun 28 '18 at 22:08
  • \$\begingroup\$ Yea I've read that article, and been to the affiliated ulpi.org site, but when I am scavenging through datasheets I see no mention of this protocol other than one IC: Texas instruments' TUSB1310. (which is NRND so that doesn't help). I am not sure if I should just be assuming that this protocol is being used. \$\endgroup\$ – alex messina Jun 28 '18 at 22:11
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ULPI specifications are limited to USB 2.0 data rates only, 480 Mbps maximum. There is no USB 3.x PHYs that can possibly use ULPI for susper-speed rates. The high-bandwidth (5000 Mbps and 10000 MBbps) link that is used in USB Super-Speed PHYs is called "PIPE3" interface.

However, since the USB 3.x provides backward compatibility simply by running the new super-speed hardware in parallel with legacy USB2 hardware, a USB 3.x PHY must support both channels, Super-Speed, and the legacy USB2.0 signaling, and therefore must use BOTH interfaces, PIPE3 and ULPI, see this Texas Instruments block diagram,

enter image description here

AFAIK, all designs I saw (Cadence, Synopsis, SiBridge, etc.), all are using separate channel (UTMI+ or ULPI) for legacy USB 2.0 support.

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