1. Brief introduction to SX1280

Sx1280 half-duplex rf transceiver of SX1200 series from Semtech working at 2.4GHz features super low power, with ic covering various PHY and modulation modes,such as LORA, FLRC,GFSK.Special modulation and handling modes enable much longer transmission length for LORA and FLRC, and GFSK is compatible with BLE. Excellent low power, SoC DC-DC and Time-of-flight make the chip function even better, good for smart home, security system, GPS, wireless ranging,wearable devices, smart bracelet and health management, etc.

2. Brief introduction to E28-2G4M12S

E28-2G4M12S is small size 2.4GHz module designed by Chengdu Ebyte，operating at 2.400 ~ 2.500GHz with max. Power of 12.5dBm. They feature ultra-low power consumption, high performance built-in PCB antenna and strong penetration ability.  The longest distance is 2km. It is hardware module, not programmed, thus users need to carry out secondary development.

3. E28-2G4M12S PCB design

XTAL is used in SX1280 to provide clock;RF PCB consists of simple LC matching circuit and one elliptic filter, connecting to 2.4GHz antenna;The connection of L4 is to make a high-efficiency step-down DC-DC converter to power the RF part of the chip.

4. BOM list is as below:

5. Reference design for PCB layout