VT-SX1278-433M is based on RF Transceiver SX1278 of SEMTECH,it’s a small size and ultra low power UHF wireless module. SX1278 is a low cost true single chip UHF transmitter designed for very low power wireless applications. The circuit is mainly intended for the ISM (Industrial, Scientific and Medical) and SRD (Short Range Device) frequency bands at 315 and 433 MHz, The MAX RF output power can be set as high as +20dBm, with data rate as high as 300Kbps. The module integrated many RF functions thus you can use it conveniently and reducing your development time.
Test operating conditions:Ta=25°C,VCC=3.3V if nothing else stated.
Operating supply voltage
Can be programmable to other frequency in bands 410~525MHz
TX current consumption
RX current consumption
Sleep State current consumption
Refer to IC operation states
Spurious emissions and harmonics
TX power +20dBm.
0.8kBaud data rata, +20dBm output power.
Storage temperature range
See more in PCB description
1. The module transmission data rate will affect Transmission distance ,the higher the data rate , the closer the distance, and the lower the receiving sensitivity.
2. The supply voltage to the module will affect TX power, in the operating supply voltage range, the lower the voltage, the lower the TX power.
3. The module central frequency will change as the operating temperature change, use it under suggest temperature, the module can work well.
4. The antenna will strongly affect the communication distance, please select matched antenna and connect it correctly.
5. The module mount will affect the communication distance.
1.8 V - 3.7 V analog power supply connection.
Connect to the system ground.
Reset, active low
Serial configuration interface, data input.
Serial configuration interface, clock input.
Serial configuration interface, data output.
Optional general output pin when CSN is high.
Serial configuration interface, chip select, active low.
RF output signal from PA, connect to the Antenna.
Packaging & Shipping
Reason and Solution
1.The power supply connect not well, check the module VCC whether it is out of maximum rating.
2.The signal line connect not well, check the module SPI interface.
3.The settings of the transmitter module and receiver module are not the same. Check these modules’ register configuration.
4.Signal block. If the transmitter work with a high TX power, and the receiver was put at a short distance(<0.5m), maybe there is a signal block to make no communication.
Communication distance is too short
1.The application environment is too bad or the antenna is shield. Put the antenna to a better place outside or higher throw a coaxial line , replace it with a higher gain antenna.
2.The work space contains a same frequency interference source, or a strong magnetic field interference,power source disturbance. Try to change the carrier frequency or get far away from the source of the disturbance.
3.The power supply is not strong. Check the voltage and the current whether it is enough.
High data error
1.The power supply ripple is too big, Change the power supply.
2.Check the module register configuration, it is recommended to set as the CC1120-datasheet.
3.There is a carrier frequency interference, change the channel.
4.The antenna unmatched to the module RF interface, change another matched antenna.