When working with LoRa (Long Range) communication, choosing the right transceiver module is crucial for optimizing range, power consumption, and application performance. The SX1262, SX1278, and SX1276 are all popular transceiver modules from Semtech, each offering a range of features suitable for different IoT and wireless communication applications. This guide will help you understand the key differences between these three modules and assist in selecting the most suitable one for your project.
SX1278/SX1276 is a long-range, low-power wireless transceiver launched by Semtech in 2013. It is a high-performance IoT wireless transceiver with a special LoRa modulation, which increases the communication range to some extent.
1.SX1262
The SX1262 is part of Semtech's latest generation of LoRa transceivers, offering improved performance over the SX127x series. It is built with a focus on efficiency, extended range, and lower power consumption, making it ideal for modern IoT applications.
2.SX1278
The SX1278 is a widely used LoRa transceiver, known for its long-range communication capabilities, especially in the sub-1 GHz frequency range. It is part of the previous generation of LoRa modules and remains popular for long-range IoT communication projects.
3.SX1276
The SX1276 is very similar to the SX1278 but supports a wider frequency range and additional features. It provides excellent range and reliability for LoRa-based applications, especially in the 433 MHz and 868 MHz bands.
SX1278 and SX1276 are packaged in the way, both are packaged in 6x6mm
and 28-pin QFN. With a large chip size and radio frequency peripherals,
the RF module size is also large. There are only two pins are different,
the 21st and 22nd pins of SX1278 are GND, while the 21st pin of the
SX1276 is RFI_HF and the 22nd pin is RFO_HF.
The package of SX1262 is 4x4mm, 24-pin QFN. The chip size is small, so RF modules size is also small. Pins are shown below.
Parameter | SX1262 | SX1278 | SX1276 |
Frequency Range | 150 MHz to 960 MHz | 433 MHz, 868 MHz, 915 MHz | 137 MHz to 1020 MHz (model-dependent) |
Modulation Schemes | LoRa, FSK, GFSK, MSK, GMSK | LoRa, FSK, GFSK, MSK, GMSK | LoRa, FSK, GFSK, MSK, GMSK |
Spreading Factors | 7 to 12 (configurable) | 6 to 12 (configurable) | 6 to 12 (configurable) |
Output Power | Up to +22 dBm | Up to +20 dBm | Up to +20 dBm |
Sensitivity (LoRa) | Down to -148 dBm | Down to -139 dBm | Down to -139 dBm |
Receiver Current | 4.8 mA (standby), 11 mA (Rx, LoRa) | 10.3 mA (standby), 14 mA (Rx, LoRa) | 10.3 mA (standby), 10.6 mA (Rx, LoRa) |
Transmitter Current | 23 mA (Tx, +14 dBm) to 139 mA (+22 dBm) | 120 mA (Tx, +20 dBm) | 120 mA (Tx, +20 dBm) |
Sleep Current | 600 nA | 0.2 µA | 1.5 µA |
Operating Temperature | -40°C ~+85°C | -40°C ~+85°C | -40°C ~+85°C |
Interfaces | SPI, I2C, UART | SPI, I2C, UART | SPI, I2C, UART |
Both SX1262 and SX1278/SX1276 have a variety of modulation methods, including LoRa and traditional (G) FSK modulation. LoRa modulation itself is the highlight of these three chips.
Both
the SX1262 and SX1278/SX1276 can use the TCXO crystal oscillator. If the
TCXO crystal oscillator is used, the XTB pin is not connected. However,
the 6th pin (DIO3) of the SX1262 can be used to power the TCXO crystal
oscillator. It only requires software configuration.
When using
XTAL, SX1278/SX1276 need to add external matching capacitors; but SX1262 does
not need, can be adjusted directly through the software.
The SX1278 supports frequency 137-525MHz, the RF transmitting output pin is pin 27(PA_BOOST) or pin 28(RFO_LF), the RF receiving input pin is pin 1(RFI_LF). The SX1276 supports frequency 137-1020 MHz, when using 137-525MHz, the RF transmitting output pin must be pin 27(PA_BOOST) or pin 28(RFO_LF), the RF receiving input pin must be pin 1(RFI_LF), when using 862-1020MHz, the RF transmitting output pin must be pin 27(PA_BOOST) or pin 22(RFO_HF), the RF receiving input pin must be pin 21(RFI_HF). From this point of view, the SX1276 can be understood as an enhanced version of the SX1278.
The SX1262 supports frequency 150-960 MHz, the RF transmitting output pin is pin 23(RFO), and the RF receiving input pins are pin 21(RFI_P) and pin 22(RFI_N). When changing the frequency band, there is no need to replace the pin, adjust the RF circuit parameters.
The
SX1278/6 has only one power supply mode, the maximum transmitting power
is 20dBm. To achieve the maximum transmitting power, the 27th pin
(PA_BOOST) must be used, and the emission current is 120mA@20dBm.
The
SX1262 has a maximum transmitting power of 22dBm and has two power
supply modes, a low-dropout regulator (LDO) and a high-efficiency
step-down DC-DC converter. In the DC-DC mode, the emission current is
118mA@22dBm.
The receiving current of SX1278/6 is about 12mA, in the
DC-DC mode, the receiving current of SX1262 is about 5mA. The highest
sensitivity of the three is -148dBm.
Under LoRa modulation, the SX1278/SX1276 has a spreading factor of 6-12, BW of 7.8-500 kHz, and an airdata rate of 0.018-37.5 kbps. The SX1262 has a spreading factor of 5-12, BW 7.81-500kHz and an airdata rate of 0.018-62.5kbps. It shows that under LoRa modulation, the SX1262 can have much higher airdata rate than the SX1278/SX1276.
Choose SX1262 if:
You need the best range and power efficiency.
Your application requires global frequency support (150 MHz to 960 MHz).
You are developing battery-powered IoT devices that need extended operation time.
You need better modulation capabilities and higher spectral efficiency.
Choose SX1278 if:
You are targeting sub-1 GHz frequency bands (433 MHz or 868 MHz) and don’t need the latest generation of performance features.
You are working with longer-range communication and can sacrifice a bit of power efficiency.
Your budget is a key consideration, and you want to keep costs low.
Choose SX1276 if:
You need more frequency flexibility than the SX1278, such as supporting the 915 MHz band for US-based applications.
You want a reliable, lower-cost solution for long-range communication with some focus on higher performance than the SX1278.