SX1272MB2xAS / SX1272MB2DAS

Additional Application Code and Library Examples can be found toward the bottom of this page

SX1272MB2xAS Schematics

SX1272MB2xAS_Schematic.pdf

SX1272MB2xAS Production Folder (BOM, Layout, ...)

SX1272MB2xAS_Production_Folder.zip

SX1272 mbed Component Shield

Overview

The SX1272/73 transceivers feature the LoRaTM long range modem that provides ultra-long range spread spectrum communication and high interference immunity whilst minimising current consumption. Using Semtech’s patented LoRaTM modulation technique SX1272/73 can achieve a sensitivity of over -137 dBm using a low cost crystal and bill of materials. The high sensitivity combined with the integrated +20 dBm power amplifier yields industry leading link budget making it optimal for any application requiring range or robustness. LoRaTM also provides significant advantages in both blocking and selectivity over conventional modulation techniques, solving the traditional design compromise between range, interference immunity and energy consumption. These devices also support high performance (G)FSK modes for systems including WMBus, IEEE802.15.4g. The SX1272/73 deliver exceptional phase noise, selectivity, receiver linearity and IIP3 for significantly lower current consumption than competing devices.

LoRa™ Modulation

LoRa™, Semtech’s proprietary modulation is a spread-spectrum technique that uses wideband linear frequency modulated pulses to encode information, whose frequency increases or decreases over a certain amount of time. As with other spread-spectrum modulation techniques, LoRa™ uses the entire channel bandwidth to broadcast a signal, making it robust to channel noise. In addition, because LoRa modulation uses a broad band of the spectrum, it is also resistant to long term relative frequency error, multi-path, fading and Doppler effects.

SX1272 Features

• 157 dB maximum link budget
• +20 dBm - 100 mW constant RF output vs. V supply
• +14 dBm high efficiency PA
• Programmable bit rate up to 300 kbps
• High sensitivity: down to -137 dBm
• Bullet-proof front end: IIP3 = -12.5 dBm
• 89 dB blocking immunity
• Low RX current of 10 mA, 200 nA register retention
• Fully integrated synthesizer with a resolution of 61 Hz
• FSK, GFSK, MSK, GMSK, LORA and OOK modulations
• Built-in bit synchronizer for clock recovery
• Sync word recognition
• Preamble detection
• 127 dB+ Dynamic Range RSSI
• Automatic RF Sense with ultra-fast AFC
• Packet engine up to 64 bytes with CRC
• Built-in temperature sensor and Low Battery indicator

Connectivity

The SX1272MB2xAS is controlled through the SPI bus at a maximum speed of 10Mbps. The connections are identical on each board so that the same software can used on any boards. All “Pass through” pins are not used in the operations of the SX1272MB2xAS boards and can therefore be used in connections of other boards for various purposes. The I2C and UART have especially been let free so that a variety of sensor can be connected to the boards, and thus enable long distance control of them.

Where to buy

Additional Application Examples

1.) LoRaWAN

LoRaWAN Class A and Class C node example based on GitHub LoRaMac-node LoRaWAN MAC layer implementation