Ublox SARA-R422 - Page 4

SARA-R4 series - System integration manual
UBX-16029218 - R20 Contents Page 4 of 128
C1-Public
2.4.1 General guidelines for antenna interfaces ..................................................................................61
2.4.2 Cellular antenna RF interface (ANT) .............................................................................................65
2.4.3 GNSS antenna RF interface (ANT_GNSS) ...................................................................................68
2.4.4 Cellular and GNSS RF coexistence ................................................................................................72
2.4.5 Antenna detection interface (ANT_DET).....................................................................................75
2.5 SIM interface ..............................................................................................................................................78
2.5.1 Guidelines for SIM circuit design ...................................................................................................78
2.5.2 Guidelines for SIM layout design ...................................................................................................82
2.6 Data communication interfaces ............................................................................................................83
2.6.1 UART interface ..................................................................................................................................83
2.6.2 USB interface .....................................................................................................................................88
2.6.3 SPI interface ......................................................................................................................................91
2.6.4 SDIO interface ...................................................................................................................................91
2.6.5 DDC (I2C) interface ...........................................................................................................................91
2.7 Audio ............................................................................................................................................................94
2.7.1 Guidelines for Audio circuit design ................................................................................................94
2.8 General Purpose Input/Output ...............................................................................................................94
2.8.1 Guidelines for GPIO circuit design .................................................................................................94
2.8.2 Guidelines for general purpose input/output layout design ....................................................95
2.9 GNSS peripheral input output ................................................................................................................95
2.9.1 Guidelines for GNSS peripheral input output circuit design ....................................................95
2.9.2 Guidelines for GNSS peripheral input output layout design ....................................................95
2.10 Reserved pins (RSVD) ..............................................................................................................................96
2.11 Module placement ....................................................................................................................................96
2.12 Module footprint and paste mask .........................................................................................................97
2.13 Thermal guidelines ...................................................................................................................................98
2.14 Schematic for SARA-R4 series module integration ..........................................................................99
2.14.1 Schematic for SARA-R4 series modules .....................................................................................99
2.15 Design-in checklist ................................................................................................................................. 100
2.15.1 Schematic checklist ...................................................................................................................... 100
2.15.2 Layout checklist ............................................................................................................................. 100
2.15.3 Antenna checklist .......................................................................................................................... 101
3 Handling and soldering ................................................................................................................... 102
3.1 Packaging, shipping, storage and moisture preconditioning ....................................................... 102
3.2 Handling ................................................................................................................................................... 102
3.3 Soldering .................................................................................................................................................. 103
3.3.1 Soldering paste .............................................................................................................................. 103
3.3.2 Reflow soldering ............................................................................................................................. 103
3.3.3 Optical inspection .......................................................................................................................... 104
3.3.4 Cleaning ........................................................................................................................................... 104
3.3.5 Repeated reflow soldering ........................................................................................................... 105
3.3.6 Wave soldering ............................................................................................................................... 105
3.3.7 Hand soldering ............................................................................................................................... 105