Ebyte E22-900T22S, Руководство пользователя

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Chengdu Ebyte Electronic Technology Co., Ltd. E22-900M30S User manual
Copyright ©2012–2018, Chengdu Ebyte Electronic Technology Co.,Ltd.
7
SN Brief Connection between Module and Single Chip Microcomputer
1 The IO0
、
IO1
、
IO2
、
IO3 in MCU means the IO port of MCU.
2
DIO1
、
DIO2 is the normal IO port, which can be configured to multiple function. The DIO2 can
connect with TXEN
，
but not with the IO port of MCU. It’s used to control RF switch, see more details
in SX1262 datasheet. Also It can be floated when not in use.
3 The DIO3 is powered by a 32MHz TCXO crystal.
4
Ensure the good grounding, large area of paving, small the power supply ripple, the filter capacitor
should be increased and as close as possible to the VCC and GND pins of module.
5 It is recommended to add 200R protection resistor to RXD/TXD of external MCU.
Note:

It is recommended to use DC stabilized power supply to supply power to the module. The power supply ripple
coefficient 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. If the reverse
connection is connected, the module may be permanently damaged.

Please check the power supply to ensure that between the recommended supply voltage, if exceeding the maximum,
the module will be permanently damaged.

Please check the stability of the power supply, the voltage can not be significantly frequent.

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 beneficial for long-term stable operation.

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 traces, high-frequency analog traces, and power traces 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(All copper-covered and well grounded), and must be close to