CLM920_NC3_LTE Module Hardware User Guide
Shang Hai YUGE Information Technology co., LTD
Page 19 of 37
1.The USB interface supports high-speed (480Mbps) and full-speed (12Mbps) modes. Therefore, the trace
design needs to strictly follow the USB2.0 protocol requirements. Pay attention to the protection of the
data lines, differential traces, and control impedance of 90
Ω
.
2.In order to improve the antistatic performance of the USB interface, it is recommended to add an ESD
protection device on the data line. The equivalent capacitance of the protection device is less than 2pF.
3.The USB interface bus supply voltage is provided internally by the module and is not required externally.
At the same time, since the USB interface of the module does not provide USB bus power, the module can
only be used as a slave device of the USB bus device.
The USB interface supports the following features:
Software download upgrade
Data communication
AT Command
GNSS NMEA output, etc.
3.6 UART interface
The CLM920_NC5 Mini PCIE module provides a set of UART interfaces with a serial port level of 1.8V.
Through the serial port, you can send AT commands, print program log information, and so on.
The module serial port supports 9600, 19200, 38400, 57600, 115200, 230400bps baud rate, the
default is 115200bps.
The UART interface is defined as follows:
Table 3-8 UART serial port signal definition
Pin number
Signal name
I/O
Description
11
UART_RX
DI
Serial port receiving data
13
UART_TX
DO
Serial port to send data
23
UART_CTS
DI
User allows module to send
25
UART_RTS
DO
The module requests the user to send
If you need to use the serial port, you need to refer to the following serial port design.
Figure 3-11 UART serial port design