User's Manual

SX127X RF Module User Manual of E19 Series Modules
Copyright ©2012–2017，Chengdu Ebyte Electronic Technology Co.,Ltd
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⚫ Make sure the grounding is good, with low power ripple, also should increase filter capacitor and as close as possible to the VCC and
GND pins.
⚫ SPI communication rate should not be set too high, usually around 1M
⚫ Make sure TXEN pin is high level, RXEN pin is low level when transmitting;
make sure RXEN pin is high level, TXEN pin is low level when receiving;
make sure TXEN、RXEN pin is low level before turning off.
⚫ The register configuration can be reinitialized to obtain higher stability when the chip is invalid.
5. Production Guidance
5.1 Reflow Temperature
Preheating zone：Maximum temperature rise is 2.5℃/s；
Insulation zone：temperature: 150~190℃，time: 60~90s，Maximum temperature rise is 2.5℃/s；
Recirculation zone：Maximum temperature is 235~245℃，Above 217℃, the time will be 40~80s；
Cooling zone：Maximum cooling is 4℃/s.
5.2 Reflow Graph
6. FAQ
6.1 The communication distance is too close
⚫ When there’s straight Communication barrier, the communication distance will be reduced accordingly.
⚫ Temperature, humidity and same frequency interference will increase the rate of communication packet loss.
⚫ Ground absorption, reflected radio waves, and closing to ground will lead to poor test result.
⚫ Sea water has a strong ability to absorb radio waves, so test near the sea is not recommended .
⚫ If antennas surrounded by metal items or placed in metal shell, the signal will be weakened badly.
⚫ Power register is set wrongly or air data rate too high.(The higher the air data rate, the closer the distance.
⚫ In room temperature, the power voltage will be less than 2.5V. The lower the the power voltage, the smaller the power.
⚫ The antenna is unmatched to the module or the quality of antenna.