Chengdu Ebyte Electronic Technology Co.,Ltd.
E220-400R30D User Manual
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Chengdu Ebyte Electronic Technology Co.,Ltd.
11
9 Hardware design
It is recommended to use DC regulatory power supply to power the module, the power ripple coefficient is as small
as possible, the module needs to be reliably grounded;
Please notice that the correct connection of the power supply positive and negative poles, such as back-linking, may
cause permanent damage to the module;
Please check the power supply to ensure that between the recommended supply voltage, if the maximum value is
exceeded, the module will be permanently damaged;
Please check the stability of the power supply, the voltage can not fluctuate significantly and frequently;
When designing power supply circuits for modules, it is often recommended to retain more than 30% of the residual
amount, and the whole machine is good for long-term stable operation;
The module should be kept as far away as possible from the power supply, transformers, high-frequency wiring and
other parts of the electromagnetic interference;
High-frequency digital wiring, high-frequency analog wiring, power cable must avoid the module below, if you
really need to go under the module, suppose the module is welded under the Top Layer, in the module contact part
of the Top Layer paved copper (all copper paved and well grounded), must be close to the module digital part and
the wire in The bottom Layer;
Assuming that the module is welded or placed on Top Layer, it is also wrong to walk freely on TheBottom Layer or
other layers, which can affect the stray and reception sensitivity of the module to varying degrees;
Assuming that there is a large electromagnetic interference around the module of the device will also greatly affect
the performance of the module, with the intensity of interference recommended appropriately away from the
module, if circumstances permit to do appropriate isolation and shielding;
Assuming that there is a large electromagnetic interference around the module (high-frequency digital,
high-frequency analog, power cable) will also greatly affect the performance of the module, with the intensity of
interference recommended appropriately away from the module, if circumstances permit to do appropriate isolation
and shielding;
If the communication line uses a 5V level, the 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 also 2.4GHz TTL protocol, e.g. USB 3.0;
Antenna installation structure has a great impact on module performance, it is necessary to ensure that the antenna
exposed and preferably vertical upward;
When the module is installed inside the enclosure, the antenna can be extended to the outside of the enclosure using
a high-quality antenna extension cable;
The antenna must not be installed inside the metal case, which will result in a significant reduction in transmission
distance.
10 FQA
10.1 The transmission distance is not ideal
When there is a straight-line communication barrier, the communication distance will be attenuated accordingly;
