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Application note
COMPANY PUBLIC
Rev. 1.1 — 19 June 2018
345311
8. List of figures
Fig 1. NFC communication modes .............................. 4
Fig 2. Magnetic coupling between reader (PCD) and
card (PICC) ....................................................... 5
Fig 3. PICC Classes according to the ISO/IEC 14443 6
Fig 4. ISO/IEC 10373-6 ReferencePICC ..................... 7
Fig 5. ISO/IEC 10373-6 Reference PICC Class 1 ....... 7
Fig 6. EMVCo POS operating volume requirement... 10
Fig 7. EMVCo POS Reader antenna size ................. 11
Fig 8. NFC Forum operating volume ......................... 12
Fig 9. PCD & PICC Antenna coil system .................. 13
Fig 10. Inductance examples versus coil radius ......... 15
Fig 11. Load modulation ............................................. 15
Fig 12. Coupling coefficient vs PCD antenna radius ... 16
Fig 13. Maximum coupling vs antenna size ................ 17
Fig 14. Operating distance x versus antenna size ...... 18
Fig 15. Magnitude of field strength in 1 cm distance ... 19
Fig 16. PN5180 Layout Reference Board Top layer ... 20
Fig 17. PN5180 Layout Reference Board Bottom layer
........................................................................ 21
Fig 18. Typical PN5180 analog circuit ......................... 22
Fig 19. Antenna circuit ................................................ 22
Fig 20. ITVDD versus antenna impedance ................. 24
Fig 21. PN5180 Reader only antenna matching circuit
........................................................................ 25
Fig 22. Measurement 1 Antenna coil of PN512
Blueboard........................................................ 26
Fig 23. Measurement 2 Antenna coil of PN512
Blueboard........................................................ 26
Fig 24. Tuning options ................................................ 29
Fig 25. Antenna matching calculation (asymmetrical
tuning) ............................................................. 31
Fig 26. RFSIM99 Schematic ....................................... 32
Fig 27. RFSIM99 Simulation result ............................. 33
Fig 28. Impedance measurement example ................. 34
Fig 29. Measurement result of first assembly ............. 35
Fig 30. Impedance adaptation in the simulation (result)
........................................................................ 36
Fig 31. Impedance adaptation in the simulation (circuit)
........................................................................ 36
Fig 32. Final tuning simulation .................................... 37
Fig 33. Final tuning measurement result ..................... 38
Fig 34. Antenna impedance example with Reference
PICC loading ................................................... 39
Fig 35. Antenna impedance example with smart phone
loading ............................................................ 40
Fig 36. RM Antenna matching with low and high
impedance ...................................................... 41
Fig 37. NFC antenna in RM ........................................ 42
Fig 38. Impedance of the NFC antenna in RM ............ 42
Fig 39. NFC antenna in CM ........................................ 43
Fig 40. Impedance of NFC antenna in CM .................. 43
Fig 41. TX_CLK_MODE_RM ...................................... 45
Fig 42. Tx envelope shaping ....................................... 46
Fig 43. PN5180 Rx block diagram ............................... 47
Fig 44. Type B response with test signals ................... 50
Fig 45. Test signals for Type B, comparison of RxGain
........................................................................ 51
Fig 46. Test signals for Type B, comparison of HPCF 51
Fig 47. Type B without Card response ........................ 52
Fig 48. Type B with Card response ............................. 53
Fig 49. Examples of Vector Network Analyzers .......... 54
Fig 50. VNA/J from DL2SBA (refer to [13]) ................. 55
Fig 51. Impedance Measurement result example (Smith
chart) ............................................................... 55
Fig 52. Measurement connector and calibration kit ..... 57
Fig 53. Calibration result ............................................. 57