Datasheet

Table Of Contents

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SX1272/73

WIRELESS, SENSING & TIMING DATASHEET

Rev. 2 - July 2014

1. General Description

The SX1272/73 incorporates the LoRa

spread spectrum modem which is capable of achieving significantly longer range

than existing systems based on FSK or OOK modulation. With this new modulation scheme sensitivities 8 dB better than

equivalent data rate FSK can be achieved with a low-cost, low-tolerance crystal reference. This increase in link budget

provides much longer range and robustness without the need for a TCXO or external amplification. LoRa

Also provides

significant advances in selectivity and blocking performance, further improving communication reliability. For maximum

flexibility the user may decide on the spread spectrum modulation bandwidth (BW), spreading factor (SF) and error

correction rate (CR). Another benefit of the spread modulation is that each spreading factor is orthogonal - thus multiple

transmitted signals can occupy the same channel without interfering. This also permits simple coexistence with existing

FSK based systems. Standard GFSK, FSK, OOK, and GMSK modulation is also provided to allow compatibility with

existing systems or standards such as wireless MBUS and IEEE 802.15.4g.

The SX1272 offers three bandwidth options of 125 kHz, 250 kHz, and 500 kHz with spreading factors ranging from 6 to 12.

The SX1273 offers the same bandwidth options with spreading factors from 6 to 9.

1.1. Simplified Block Diagram

Figure 1. SX1272/73 Block Diagram