Datasheet

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Table of contents
SX1272/73
WIRELESS, SENSING & TIMING DATASHEET
Rev. 2 - July 2014
©2014 Semtech Corporation
4.2.12. Digital IO Pins Mapping ...........................................................................................................................65
4.2.13. Continuous Mode ....................................................................................................................................66
4.2.13.1. General Description ........................................................................................................................ 66
4.2.13.2. Tx Processing ................................................................................................................................. 66
4.2.13.3. Rx Processing ................................................................................................................................. 67
4.2.14. Packet Mode ........................................................................................................................................... 67
4.2.14.1. General Description ........................................................................................................................ 67
4.2.14.2. Packet Format ................................................................................................................................. 68
4.2.14.3. Tx Processing ................................................................................................................................. 71
4.2.14.4. Rx Processing ................................................................................................................................. 71
4.2.14.5. Handling Large Packets .................................................................................................................. 72
4.2.14.6. Packet Filtering ............................................................................................................................... 72
4.2.14.7. DC-Free Data Mechanisms............................................................................................................. 74
4.2.14.8. Beacon Tx Mode ............................................................................................................................. 75
4.2.15. io-homecontrol® Compatibility Mode ...................................................................................................... 75
4.3. SPI Interface ..................................................................................................................................................76
5. SX1272/73 Analog & RF Frontend Electronics...................................................................................................... 78
5.1. Power Supply Strategy .................................................................................................................................. 78
5.2. Low Battery Detector ..................................................................................................................................... 78
5.3. Frequency Synthesis ..................................................................................................................................... 78
5.3.1. Crystal Oscillator ....................................................................................................................................... 78
5.3.2. CLKOUT Output ........................................................................................................................................ 79
5.3.3. PLL ............................................................................................................................................................ 79
5.3.4. RC Oscillator ............................................................................................................................................. 81
5.4. Transmitter Description ..................................................................................................................................82
5.4.1. Architecture Description ............................................................................................................................ 82
5.4.2. RF Power Amplifiers.................................................................................................................................. 82
5.4.3. High Power +20 dBm Operation ............................................................................................................... 83
5.4.4. Over Current Protection ............................................................................................................................84
5.5. Receiver Description...................................................................................................................................... 84
5.5.1. Overview ................................................................................................................................................... 84
5.5.2. Receiver Enabled and Receiver Active States.......................................................................................... 84
5.5.3. Automatic Gain Control In FSK/OOK Mode .............................................................................................. 85
5.5.4. RSSI in FSK/OOK Mode ........................................................................................................................... 86
5.5.5. RSSI and SNR in LoRaTM Mode.............................................................................................................. 87
5.5.6. Channel Filter ............................................................................................................................................ 88
5.5.7. Temperature Measurement....................................................................................................................... 88
6. Description of the Registers................................................................................................................................... 90
6.1. Register Table Summary ............................................................................................................................... 90
6.2. FSK/OOK Mode Register Map .......................................................................................................................93
6.3. LoRaTM Mode Register Map....................................................................................................................... 107
7. Application Information ........................................................................................................................................ 114