Chengdu Ebyte Electronic Technology Co.,Ltd. E28-2G4M27S User Manua
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Chengdu Ebyte Electronic Technology Co.,Ltd.
5
14
DIO2
Input/Output
GPIO(refer to SX1280 Datasheet for details)
15
DIO3
Input/Output
GPIO(refer to SX1280 Datasheet for details)
16
GND
Ground, connecting to power source reference ground
4 Basic Operation
4.1 Hardware design
⚫
It is recommended to use a DC stabilized power supply. The power supply ripple factor is as small as possible, and
the module needs to be reliably grounded;
⚫
Please pay attention to the correct connection of the positive and negative poles of the power supply. Reverse
connection may cause permanent damage to the module;
⚫
Please check the power supply to ensure it is within the recommended voltage otherwise when it exceeds the
maximum value the module will be permanently damaged;
⚫
Please check the stability of the power supply, the voltage can not be fluctuated frequently;
⚫
When designing current supply circuit, 30% margin is recommended to be remained so as to ensure long-term stable
operation of the whole module;
⚫
The module should be as far away as possible from the power supply, transformers, high-frequency wiring and other
parts with large electromagnetic interference;
⚫
High-frequency digital routing, high-frequency analog routing, and power routing must be avoided under the module.
If it is necessary to pass through the module, assume that the module is soldered to the Top Layer, and the copper is
spread on the Top Layer of the module contact part(well grounded), it must be close to the digital part of the module
and routed in the Bottom Layer;
⚫
Assuming the module is soldered or placed over the Top Layer, it is wrong to randomly route over the Bottom Layer
or other layers, which will affect the module's spurs and receiving sensitivity to varying degrees;
⚫
It is assumed that there are devices with large electromagnetic interference around the module that will greatly affect
the performance. It is recommended to keep them away from the module according to the strength of the interference.
If necessary, appropriate isolation and shielding can be done;
⚫
Assume that there are traces with large electromagnetic interference (high-frequency digital, high-frequency analog,
power traces) around the module that will greatly affect the performance of the module. It is recommended to stay
away from the module according to the strength of the interference.If necessary, appropriate isolation and shielding
can be done;
⚫
If the communication line uses a 5V level, a 1k-5.1k resistor must be connected in series (not recommended, there is
still a risk of damage);
⚫
Try to stay away from some physical layers such as TTL protocol at 2.4GHz , for example: USB3.0;
⚫
The antenna installation position has a great influence on the performance of the module. Make sure that the antenna
is exposed, preferably vertically. When the module is installed inside the shield, a high-quality antenna extension
cable can be used to extend the antenna outside;
⚫
The antenna must not be installed inside the metal case, which will greatly reduce the transmission distance.
