User's Guide

LE910Cx HW User Guide
Doc#: 1VV0301298
Rev. 13.0 Page 67 of 124 2019-07-15
USB Port
The LE910Cx module includes a Universal Serial Bus (USB) transceiver, which operates
at USB high-speed (480Mbits/sec). It can also operate with USB full-speed hosts
(12Mbits/sec).
It is compliant with the USB 2.0 specification and can be used for control and data
transfers as well as for diagnostic monitoring and firmware update.
The USB port is typically the main interface between the LE910Cx module and OEM
hardware.
NOTE:
The USB_D+ and USB_D- signals have a clock rate of 480 MHz. The signal
traces must be routed carefully. Minimize trace lengths, number of vias, and
capacitive loading. The impedance value should be as close as possible to
90 Ohms differential.
Table 24 lists the USB interface signals.
Table 24: USB Interface Signals
Signal
Pad
No.
Usage
USB_VBUS
A13
Power and cable detection for the internal USB transceiver.
Acceptable input voltage range 2.5V – 5.5V @ max 5 mA
consumption
USB_D-
C15
Minus (-) line of the differential, bi-directional USB signal to/from
the peripheral device
USB_D+
B15
Plus (+) line of the differential, bi-directional USB signal to/from
the peripheral device
USB_ID
A14
Used for USB OTG to determine host or client mode
NOTE:
USB_VBUS input power is internally used to detect the USB port and start
the enumeration process.
It is a power supply pin with a maximum consumption of 5 mA.
Do not use pull up or a voltage divider for sourcing this supply