LE910C1
Hardware User Guide
1VV0301298 Rev. 1.08 - 2017-11-14
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8.1.
USB Port
The LE910C1 module includes a Universal Serial Bus (USB) transceiver, which operates at USB high-
speed (480 Mbits/sec). It can also operate with USB full-speed hosts (12 Mbits/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 LE910C1 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 23 lists the USB interface signals.
Table 23: 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 in order 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
NOTE:
Even if USB communication is not used, it is still highly recommended to place an optional USB connector
on the application board.
At least test points of the USB signals are required since the USB physical communication is needed in
the case of SW update.
NOTE
USB OTG support is optional and is not supported by default. An external 5V power supply is required on
the application board for supporting USB OTG