SMSC EVB-USB3340, Руководство пользователя

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EVB-USB3340 USB Transceiver Evaluation Board User Manual
SMSC USB3340 EVB 3 Revision 1.1 (12-14-10)
USER MANUAL
2.3 Edge Connector for Digital I/O
The T&MT edge connector is compliant to the ULPI specification. Part numbers and manufacturers for
this connector and it’s mate are given in
Table 2.1 .
2.4 REFCLK Frequency Selection
The USB3340 EVB offers a user selectable reference clock frequency. R25 - R30 are used to configure
the REFCLK[2:0] signals which will select the reference clock frequency desired on the USB3340 EVB.
Ensure that the frequency of the reference clock or reference crystal being used matches the desired
operation frequency configured based on
Table 2.2 below. By default, the USB3340 EVB is configured
for 26MHz REFCLK operation.
2.5 USB Connector
A standard Mini-AB connector is provided to attach a USB cable or connector. Provision is made on
the PCB to accept a Micro-AB connector. See the bill of materials in
Section 6 for connector part
numbers. Do not substitute a different part number for the Mini-AB receptacle or a short circuit of the
USB signals may result at the micro-AB connector PCB footprint.
2.6 VBUS Present Detection
The USB controller must detect VBUS when a USB cable is attached in device mode or when the USB
controller turns on VBUS in host or OTG mode. The USB connector VBUS signal is connected to the
VBUS pin of the USB3340. The USB3340 includes all of the comparators required to detect VBUS and
report the state of VBUS to the USB controller via the ULPI bus.
Table 2.1 Edge Connector on the USB3340 EVB
PART NUMBER DESCRIPTION MANUFACTURER
2-557101-5 100 pin edge connector on USB3340 EVB AMP
2-557-101-5 Mating connector to the USB3340 EVB AMP
1-1734037-0 Alternate 100 pin edge connector for USB3340 EVB TYCO
1-1734099-0 Alternate mating connector to the USB3340 EVB TYCO
Table 2.2 Reference Frequency Selection Resistor Configurations
R25 R26 R27 R28 R29 R30 REFCLK FREQUENCY
INSTALL EMPTY INSTALL EMPTY EMPTY INSTALL 26.0 MHz (Default)
EMPTY INSTALL INSTALL EMPTY EMPTY INSTALL 12.0 MHz
EMPTY INSTALL EMPTY INSTALL EMPTY INSTALL 52.0 MHz
INSTALL EMPTY INSTALL EMPTY INSTALL EMPTY 24.0 MHz
INSTALL EMPTY EMPTY INSTALL INSTALL EMPTY 19.2 MHz
EMPTY INSTALL INSTALL EMPTY INSTALL EMPTY 27.0 MHz
EMPTY INSTALL EMPTY INSTALL INSTALL EMPTY 38.4 MHz
INSTALL EMPTY EMPTY INSTALL EMPTY INSTALL 13.0 MHz