Chengdu Ebyte Electronic Technology Co., Ltd.
E220-900T22D User Manual
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Chengdu Ebyte Electronic Technology Co., Ltd.
18
9. Hardware Design
It is recommended to use a DC stabilized power supply to supply power to the module. The power ripple coefficient should be as
small as possible, and the module must 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 that it is within the recommended power supply voltage. If it exceeds the maximum
value, it will cause permanent damage to the module;
Please check the stability of the power supply, the voltage should not fluctuate greatly and frequently;
When designing the power supply circuit for the module, it is often recommended to reserve more than 30% of the margin, and
the whole machine is conducive to long-term stable operation;
The module should be as far away as possible from power supply, transformer, high frequency wiring and other parts with large
electromagnetic interference;
High-frequency digital traces, high-frequency analog traces, and power traces must avoid under the module. If they really need
to pass under the module, assuming that the module is soldered to the Top Layer, lay copper on the Top Layer of the contact part
of the module (all copper and Good grounding), must be close to the digital part of the module and routed in the Bottom Layer;
Assuming that the module is soldered or placed on the Top Layer, it is also wrong to randomly route the wires on the Bottom
Layer or other layers, which will affect the stray and receiving sensitivity of the module to varying degrees;
Assuming that there are devices with large electromagnetic interference around the module, it will greatly affect the performance
of the module. According to the intensity of the interference, it is recommended to stay away from the module. If the situation
permits, proper isolation and shielding can be done;
Assuming that there are traces with large electromagnetic interference around the module (high-frequency digital,
high-frequency analog, power wiring), it will also greatly affect the performance of the module. According to the intensity of the
interference, it is recommended to stay away from the module. Isolation and shielding;
Try to stay away from part of the physical layer that is also 2.4GHz TTL protocol, such as: USB3.0;
The antenna installation structure has a great influence on the performance of the module. Make sure that the antenna is exposed
and it is best to be vertically upward;
When the module is installed inside the case, a high-quality antenna extension cable can be used to extend the antenna to the
outside of the case;
The antenna must not be installed inside the metal shell, which will greatly reduce the transmission distance.
