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hengdu Ebyte Electronic Technology Co., Ltd.
E220-900T30S User Manual
Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co., Ltd.
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9. Hardware Design
It is recommended to use the DC stabilized power supply module for power supply, the power supply ripple coefficient is 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 expected
voltage, it will cause permanent damage to the module;
Please check the stability of the power supply, the voltage cannot be extended to the maximum value;
When designing the power supply circuit for the module, it is often recommended to reserve more than 30% margin, so that the
whole machine is conducive to long-term stable operation;
The module should be as far away as possible from the power supply, transformer, high-frequency wiring and other
electromagnetic interference parts;
High-frequency digital wiring, high-frequency analog wiring, and power wiring must avoid the bottom of the module. If it really
needs to go under the module, assume that the module is soldered on the top layer, and ground copper on the top layer of the
contact part of the module (all copper and well grounded), must be close to the digital part of the module and routed on 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 that interfere with electromagnetic interference around the module, it will also greatly affect the
performance of the module. According to the strength of the interference, it is recommended to separate the modules
appropriately. If the situation permits, proper isolation and shielding can be done;
Assuming that there are traces (high-frequency digital, high-frequency analog, power traces) that interfere with electromagnetic
interference around the module, it will greatly affect the performance of the module. According to the strength of the interference,
it is recommended to divide the module appropriately. If the situation permits, you can do the appropriate Isolation and shielding;
If the communication line uses 5V parasitic, a 1k-5.1k resistor must be connected in series (not recommended, there is still a risk
of damage);
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 an interference effect on the performance of the module, which can ensure that the antenna
is exposed and preferably 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 shorten the transmission distance.
