Usb Interface Definition; Usb2.0 Interface Application; Usb3.0 Interface Application - Fibocom L850-GL Series Hardware Manual

configured in practical application.

3.4.2.1 USB Interface Definition

Pin# Pin Name
7 USB_D+
9 USB_D-
29 USB3.0_TX-
31 USB3.0_TX+
35 USB3.0_RX-
37 USB3.0_RX+

3.4.2.2 USB2.0 Interface Application

The reference circuit is shown in Figure 3-16:
USB_D- and USB_D+ are high speed differential signal lines with the maximum transfer rate of 480 Mbps,
so the following rules should be followed carefully in the case of PCB layout:
USB_D- and USB_D+ signal lines should have the differential impedance of 90Ω.

USB_D- and USB_D+ signal lines should be parallel and have the equal length. The right angle routing

should be avoided.
USB_D- and USB_D+ signal lines should be routed on the layer that is adjacent to the ground layer,

and wrapped with GND vertically and horizontally.

3.4.2.3 USB3.0 Interface Application

The reference circuit is shown in Figure 3-17:
Reproduction forbidden without Fibocom Wireless Inc. written authorization - All Rights Reserved.
FIBOCOM L850-GL Series Hardware Guide
I/O Description
I/O USB data plus
I/O USB data minus
O USB3.0 transmit data minus
O USB3.0 transmit data plus
I USB3.0 receive data minus
I USB3.0 receive data plus
Figure 3-16 Reference circuit for USB 2.0 interface
Type
0.3---3V,
USB2.0
0.3---3V,
USB2.0
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