Users Manual Part 1

SIM8260A_Hardware Design_V1.05
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3.4.1 VDD_EXT Reference Circuit
The following figure is the reference circuit diagram of the VDD_EXT pin periphery of the module.
Figure 17: Module VDD_EXT peripheral reference circuit

It is recommended to place a TVS protection tube near the VDD_EXT pin of the module to protect
the module pins. The recommended TVS models are shown in the following table.

It is recommended to connect a 2.2R resistor in series with the VDD_EXT pin close to the module
for ESD protection.
Table 19: Module VDD_EXT pin protection tube TVS recommended materials
NO.
Manufacturer
Model
Operating
Voltage
package
Name
1
ON
ESD9L5.0ST5G
3.3V
SOD-923
D1
2
YAGEO
RC0402JR072R2L
-
0402
R1
3.5 USB Interface
SIM8260A has one USB controller，which complies with USB3.1 and USB2.0 specifications. The
high-speed PHY and super-speed PHY share the same USB 3.1 Gen2 controller, customers can choose
USB3.1 or USB2.0 for their needs. USB3.1 Gen2 data rate is up to 10Gbps.
The USB interface is used for AT command communication, data transmission, GNSS NMEA output,
firmware upgrade and software debugging.
SIM8260A supports USB suspend and resume mechanism, which can save power consumption. If there is
no data transmission on the USB bus, module will enter suspend mode automatically. The following figure
is the USB reference circuit.
NOTE