CLM920_RC3(RV3 RE3)LCC Series CAT1 Module Hardware Manual
Shanghai YUGE Information Technology Co., Ltd.
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3.5 USB interface
CLM920_RC3 module supports one USB2.0 interface, supports slave mode, and does not
support USB charging function. The USB cable must comply with the USB2.0 protocol
specification, and the USB interface is defined as follows
：
Table 3-12 USB interface pin definition
Pin
Signal name
IO
Description
69
USB_DP
IO
USB differential
70
USB_DM
IO
USB differential signal
71
USB_VBUS
PI
USB insertion detection
As a USB slave device, the module supports USB sleep and wake-up mechanisms. The
reference circuit of the USB interface application is as follows
：
Figure 3-13 USB connection design circuit diagram
USB supports high-speed (480Mbps) and full-speed (12Mbps) modes, and the trace design
needs to strictly follow the USB2.0 protocol requirements, pay attention to the protection
of the data line, the differential trace, the shorter the better, as far as possible away from
high-speed signals or other common Signal, the control impedance is 90
Ω
.
To improve the anti-static performance of the USB interface, it is recommended to add
ESD protection devices on the data line, and the equivalent capacitance of the protection
device is less than 1pF. It is recommended to connect a 0 ohm resistor in series with the
