LE940B6 HW User Guide
Rev. 2.02
Page 72 of 111
2020-01-10
USB Port
The LE940B6 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.
NOTE:
With the LE940B6 module, firmware updates by the host are only possible
via USB and not possible via UART. The reason is that Titan considers it
impractical to transfer firmware binaries exceeding 100Mb via UART.
The USB port is typically the main interface between the LE940B6 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.
The pull-up, pull-down and series resistors on pins USB_D+ and USB_D- as required by
the USB 2.0 specification are included inside the module.
Table 24 lists the USB interface signals.
Table 24: USB Interface Signals
Signal
Pad
No.
Usage
USB_VBUS
A18
Power and cable detection for the internal USB transceiver.
Acceptable input voltage range 2.5V
– 5.5V @ max 5 mA
consumption
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
Provided
to
Dekra
under
NDA
Distribution
is
Prohibited
except
for
Dekra
employees
with
a Need
to
know
