User's Manual

HE910 Hardware User Guide
1vv0300925 Rev.9 – 07-02-2012
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8 USB Port
The HE910 includes one integrated universal serial bus (USB) transceiver:
USB 2.0 HS
8.1 USB 2.0 HS
This port is compliant with the USB 2.0 specifications.
The following table is listing the available signals:
PAD
Signal
I/O
Function
Type
NOTE
B15
USB_D+
I/O
USB differential Data (+)
3.3V
C15
USB_D-
I/O
USB differential Data (-)
3.3V
A13
VUSB
AI
Power sense for the internal USB
transceiver.
5V
Accepted range:
4.4V to 5.25V
The USB_DPLUS and USB_DMINUS signals have a clock rate of 480 MHz. The signal
traces should be routed carefully. Trace lengths, number of vias and capacitive
loading should be minimized. The impedance value should be as close as possible
to 90 Ohms differential.