Integration Manual

SARA-R5 series - System integration manual
UBX-19041356 - R03 Page 4 of 123
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2.4.1 General guidelines for antenna interfaces .................................................................................. 52
2.4.2 Cellular antenna RF interface (ANT) ............................................................................................. 56
2.4.3 GNSS antenna RF interface (ANT_GNSS) ................................................................................... 62
2.4.4 Cellular antenna detection interface (ANT_DET) ...................................................................... 65
2.4.5 Cellular antenna dynamic tuning control interface ................................................................... 67
2.5 SIM interface .............................................................................................................................................. 69
2.5.1 Guidelines for SIM circuit design ................................................................................................... 69
2.5.2 Guidelines for SIM layout design ................................................................................................... 73
2.6 Data communication interfaces ............................................................................................................ 74
2.6.1 UART interfaces ................................................................................................................................ 74
2.6.2 USB interface ..................................................................................................................................... 81
2.6.3 SPI interfaces .................................................................................................................................... 82
2.6.4 SDIO interface ................................................................................................................................... 82
2.6.5 DDC (I2C) interface ........................................................................................................................... 83
2.7 Audio ............................................................................................................................................................ 85
2.8 General purpose input / output (GPIO) ................................................................................................. 85
2.8.1 Guidelines for GPIO circuit design ................................................................................................. 85
2.8.2 Guidelines for general purpose input/output layout design .................................................... 86
2.9 Reserved pin (RSVD) ................................................................................................................................ 86
2.10 Module placement .................................................................................................................................... 86
2.11 Module footprint and paste mask ......................................................................................................... 87
2.12 Schematic for SARA-R5 series module integration .......................................................................... 88
2.13 Design-in checklist .................................................................................................................................... 89
2.13.1 Schematic checklist ......................................................................................................................... 89
2.13.2 Layout checklist ................................................................................................................................ 90
2.13.3 Antennas checklist ........................................................................................................................... 90
3 Handling and soldering ...................................................................................................................... 91
3.1 Packaging, shipping, storage and moisture preconditioning .......................................................... 91
3.2 Handling ...................................................................................................................................................... 91
3.3 Soldering ..................................................................................................................................................... 92
3.3.1 Soldering paste ................................................................................................................................. 92
3.3.2 Reflow soldering ................................................................................................................................ 92
3.3.3 Optical inspection ............................................................................................................................. 93
3.3.4 Cleaning .............................................................................................................................................. 93
3.3.5 Repeated reflow soldering .............................................................................................................. 94
3.3.6 Wave soldering .................................................................................................................................. 94
3.3.7 Hand soldering .................................................................................................................................. 94
3.3.8 Rework ................................................................................................................................................ 94
3.3.9 Conformal coating ............................................................................................................................ 94
3.3.10 Casting ................................................................................................................................................ 94
3.3.11 Grounding metal covers .................................................................................................................. 95
3.3.12 Use of ultrasonic processes ........................................................................................................... 95