The ZCU670 board uses a Standard Microsystems Corporation USB3320 USB 2.0 ULPI
Transceiver (U6) to support a USB connection to the host computer. A USB cable is supplied in
the ZCU670 Evaluation Kit (standard-A connector to host computer, USB 3.0 A connector to
ZCU670 board connector J18). The USB3320 is a high-speed USB 2.0 PHY supporting the UTMI
+ low pin interface (ULPI) interface standard. The ULPI standard defines the interface between
the USB controller IP and the PHY device which drives the physical USB bus. Use of the ULPI
standard reduces the interface pin count between the USB controller IP and the PHY device.
The following figure shows the USB 3.0 interface. USB 3.0 is host mode only.
Figure 12: USB Interface
SM3320
USB2.0
USB
MIO
ULPI
GTR Tx, Rx
USB3
Connector
USB
GTR
X23650-032720
The USB3320 is clocked by a 24 MHz crystal (X2). See the
Standard Microsystems Corporation
USB3320 data sheet for clocking mode details.
The interface to the USB3320 PHY is implemented through the IP in the ZU67DR RFSoC
Processor System (PS). USB OTG support is available for USB 2.0. See
for USB 2.0 jumper
settings.
Note: The shield for the USB 3.0 micro-B connector (J18) can be tied to GND by a jumper on header J20
pins 2-3 (default). The USB shield can optionally be connected through a series capacitor to GND by
installing a capacitor (body size 0402) at location C204 and jumping pins 1-2 on header J20.
The USB3320 ULPI U6 transceiver circuit (see the following figure) has a Micrel MIC2544 high-
side programmable current limit switch (U7). This switch has an open-drain output fault flag on
pin 2, which will turn on LED DS7 if overcurrent or thermal shutdown conditions are detected.
DS7 is located adjacent to the USB J18 connector (
, callout 6).
The following figure shows the ULPI U6 transceiver circuit.
Chapter 3: Board Component Descriptions
UG1532 (v1.0) March 30, 2022
ZCU670 Board User Guide
38