SX1231
DATASHEET
Page
ADVANCED COMMUNICATIONS & SENSING
Index of Figures
Figure 1. Block Diagram ................................................................................................................................................ 8
Figure 2. Pin Diagram .................................................................................................................................................... 9
Figure 3. Marking Diagram ............................................................................................................................................ 9
Figure 4. TCXO Connection ........................................................................................................................................ 16
Figure 5. Transmitter Block Diagram ........................................................................................................................... 19
Figure 6. Receiver Block Diagram ............................................................................................................................... 22
Figure 7. AGC Thresholds Settings ............................................................................................................................. 23
Figure 8. Cordic Extraction .......................................................................................................................................... 27
Figure 9. OOK Peak Demodulator Description ............................................................................................................ 27
Figure 10. Floor Threshold Optimization ..................................................................................................................... 28
Figure 11. Bit Synchronizer Description ...................................................................................................................... 29
Figure 12. FEI Process ................................................................................................................................................ 31
Figure 13. Temperature Sensor Response ................................................................................................................. 32
Figure 14. Tx Startup, FSK and OOK .......................................................................................................................... 34
Figure 15. Rx Startup - No AGC, no AFC .................................................................................................................... 35
Figure 16. Rx Startup - AGC, no AFC ......................................................................................................................... 35
Figure 17. Rx Startup - AGC and AFC ........................................................................................................................ 35
Figure 18. Listen Mode Sequence (no wanted signal is received) .............................................................................. 37
Figure 19. Listen Mode Sequence (wanted signal is received) ................................................................................... 39
Figure 20. Auto Modes of Packet Handler ................................................................................................................... 40
Figure 21. SX1231 Data Processing Conceptual View ............................................................................................... 41
Figure 22. SPI Timing Diagram (single access) .......................................................................................................... 42
Figure 23. FIFO and Shift Register (SR) ..................................................................................................................... 43
Figure 24. FifoLevel IRQ Source Behavior .................................................................................................................. 44
Figure 25. Sync Word Recognition .............................................................................................................................. 45
Figure 26. Continuous Mode Conceptual View ........................................................................................................... 47
Figure 27. Tx Processing in Continuous Mode ............................................................................................................ 47
Figure 28. Rx Processing in Continuous Mode ........................................................................................................... 48
Figure 29. Packet Mode Conceptual View ................................................................................................................... 49
Figure 30. Fixed Length Packet Format ...................................................................................................................... 50
Figure 31. Variable Length Packet Format .................................................................................................................. 50
Figure 32. Unlimited Length Packet Format ................................................................................................................ 51
Figure 33. CRC Implementation .................................................................................................................................. 55
Figure 34. Manchester Encoding/Decoding ................................................................................................................. 56
Figure 35. Data Whitening ........................................................................................................................................... 56
Figure 36. POR Timing Diagram ................................................................................................................................. 73
Figure 37. Manual Reset Timing Diagram ................................................................................................................... 74
Figure 38. Package Outline Drawing ........................................................................................................................... 75
Figure 39. Recommended Land Pattern ..................................................................................................................... 75
Figure 40. Tape & Reel Specification .......................................................................................................................... 76
Rev 2 - Nov 2009
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