u-blox ZED-F9T - Page 4

ZED-F9T-Integration Manual
3.5.4 GNSS times................................................................................................................................... 38
3.5.5 Time validity..................................................................................................................................39
3.5.6 UTC representation..................................................................................................................... 39
3.5.7 Leap seconds................................................................................................................................ 40
3.5.8 Real time clock............................................................................................................................. 40
3.5.9 Date.................................................................................................................................................40
3.6 Timing functionality............................................................................................................................. 41
3.6.1 Time pulse..................................................................................................................................... 41
3.6.2 Timemark.......................................................................................................................................45
3.7 Security (operating, monitoring and maintaining)........................................................................ 46
3.7.1 Receiver status monitoring....................................................................................................... 46
3.7.2 Spoofing detection / monitoring...............................................................................................48
3.8 u-blox protocol feature descriptions................................................................................................ 48
3.8.1 Broadcast navigation data.........................................................................................................48
3.9 Forcing a receiver reset....................................................................................................................... 54
4 Design..................................................................................................................................... 56
4.1 Pin assignment......................................................................................................................................56
4.2 Power supply..........................................................................................................................................58
4.2.1 VCC: Main supply voltage.......................................................................................................... 58
4.2.2 V_BCKP: Backup supply voltage............................................................................................... 58
4.2.3 ZED-F9T power supply............................................................................................................... 59
4.3 ZED-F9T minimal design.................................................................................................................... 59
4.4 Antenna...................................................................................................................................................60
4.4.1 Antenna bias.................................................................................................................................61
4.5 EOS/ESD precautions.......................................................................................................................... 64
4.5.1 ESD protection measures.......................................................................................................... 64
4.5.2 EOS precautions...........................................................................................................................65
4.5.3 Safety precautions...................................................................................................................... 65
4.6 Electromagnetic interference on I/O lines.......................................................................................65
4.6.1 General notes on interference issues......................................................................................66
4.6.2 In-band interference mitigation................................................................................................66
4.6.3 Out-of-band interference........................................................................................................... 67
4.7 Layout......................................................................................................................................................67
4.7.1 Placement...................................................................................................................................... 67
4.7.2 Package footprint and solder mask.........................................................................................67
4.7.3 Layout guidance........................................................................................................................... 67
4.8 Design guidance....................................................................................................................................69
4.8.1 General considerations............................................................................................................... 69
4.8.2 backup battery............................................................................................................................. 69
4.8.3 RF front-end circuit options...................................................................................................... 70
4.8.4 Antenna/ RF input....................................................................................................................... 70
4.8.5 Ground pads..................................................................................................................................71
4.8.6 Schematic design........................................................................................................................ 71
4.8.7 Layout design-in guideline......................................................................................................... 71
5 Product handling................................................................................................................. 72
5.1 ESD handling precautions.................................................................................................................. 72
5.2 Soldering.................................................................................................................................................72
5.3 Tapes....................................................................................................................................................... 75
5.4 Reels........................................................................................................................................................ 76
UBX-19005590 - R01

Contents Page 4 of 80
Advance Information