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LE920 Hardware User Guide
1vv0301026 Rev.0 - draft4 – 2013-05-
Reproduction forbidden without written authorization from Telit Communications S.p.A. - All Rights Reserved.
Page 49 of 76
8.
USB Port
The LE920 module includes a Universal Serial Bus (USB) transceiver, which operates at
USB low-speed (1.5Mbits/sec), USB full-speed (12Mbits/sec) and USB high-speed
(480Mbits/sec).
It is compliant with the USB 2.0 specification and can be used for diagnostic monitoring,
control and data transfers.
The USB_DPLUS and USB_DMINUS signals have a clock rate of 480MHz. 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.
The table below describes the USB interface signals:
Signal
LE920
Pad No.
Usage
USB_VBUS
A18
Power sense for the internal USB transceiver .
USB_D-
F19
Minus (-) line of the differential, bi-directional USB signal to/from the
peripheral device
USB D+
D19
Plus (+) line of the differential, bi-directional USB signal to/from the
peripheral device