E22-400M33S User Manual
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appropriate isolation and shielding can be done.
communication line if the use of 5V level, must be connected in series with 1k-5.1k resistors (not recommended,
there is still a risk of damage).
try to stay away from some of the physical layer is also 2.4GHz TTL protocol, for example: USB3.0.
Antenna mounting structure has a big impact on the module performance, make sure the antenna is exposed,
preferably vertically up. When the module is installed inside the case, you can use a high quality antenna extension
cable to extend the antenna to the outside of the case.
The antenna must not be installed inside the metal case, it will cause the transmission distance to be greatly
weakened.
It is recommended to add 200R protection resistors to the RXD/TXD of the external MCU.
4.2 Software Writing
This module is SX1268/PA+LNA, its driving method is fully equivalent to SX1268/SX1262, users can
operate exactly according to SX1268/SX1262 chip book.
DIO1 and DIO2 are general-purpose IO ports, which can be configured for various functions; among them, DIO2
can be connected to TXEN and not to the MCU IO port for controlling RF switch emission, see SX1262 manual for
details, which can be suspended if not used.
Internal use DIO3 for 32MHz TCXO crystal power supply (DIO3 configuration output 1.8V)
