1. ProductIntroduction

Featuring the long distance and low powercomsupution, SX1262 is the newest Sub-GHz wireless transceivers from Semtech,the frequency band covering 150-960MHz. As one high performance IoT wirelesstransceiver, SX1262 provides two modulation methods: LoRa and traditional(G)FSK, which increase the transmission distance largely.

Built in LNA, the highest receivingsensitivity of SX1262 reaches-148dBm and the transmitting power can reach+22dBm at most with PA. SX1262 has two power distribution system: LDO and highefficiency step-down DC-DC converter. With DC-DC, the lowest receiving currentcan be 4.2mA, which realizes the real low power consumption. The integrateddigital interface of SX1262 interact data with other devices via the SPI.

Figure 1  The internal frame of SX1262

2. ApplicationEnvironment

According to above introduction, SX1262 canbe applied to various application, such as, intelligent instrument, Logisticsand supply chain, Intelligent building and home, Smart city, Asset tracking,City street lamp, Health care products, Sensors for agriculture and parkingetc.

3. CircuitDesign

Application circuit 1:

Its’ features as below:

1) SX1262adopts 32MHz Passive crystal oscillator to provide clock.

2) RF circuitis divided into TX circuit and RX circuit, which are separated by RF switch.

3) The L7connection can make the SX1262 adopting the high-efficiency step-down DC-DCconverter as power distribution, which features lower receiving current.

Figure2 The circuit diagram SX1262 based on XTAL an DC-DC

Application circuit 2:

Its’ features as below:

1)     SX1262 adopts 32MHz TXCO crystal oscillator to provide clock, whichensures high accuracy rate on frequency.

2)RF circuit is divided into TX circuit andRX circuit, which are separated by RF switch.

3)The L7 connection can make the SX1262adopting the high-efficiency step-down DC-DC converter as power distribution,which features lower receiving current.

Figure 3 The circuit diagram of SX1262based on TCXO and DC-DC

Application circuit 3:

Its’ features as below:

1)     SX1262 adopts 32MHz Passive crystal oscillator to provide clock.

2)RF circuit is divided into TX circuit andRX circuit, which are separated by RF switch.

3) SX1262 adopts LDO as power distribution,which ensures bigger receiving current.

Figure4 The circuit diagram of SX1262 based on XTAL and LDO

With TCXO or XTAL option, take below PCBlayout as reference