MAX-7 / NEO-7 / LEA-7 - Hardware Integration Manual
GPS.G7-HW-11006-1 Contents
Page 5 of 55
Contents
Preface ................................................................................................................................ 3
Contents .............................................................................................................................. 5
1 Quick reference ............................................................................................................ 8
2 Hardware description .................................................................................................. 8
2.1 Overview ................................................................................................................................................................................. 8
2.2 Architecture ............................................................................................................................................................................. 8
2.3 Operating modes ..................................................................................................................................................................... 9
2.3.1 Continuous Mode ................................................................................................................................................................ 9
2.3.2 Power Save Mode ................................................................................................................................................................ 9
2.4 Configuration .......................................................................................................................................................................... 9
2.5 Connecting power ................................................................................................................................................................... 9
2.5.1 VCC: Main Supply Voltage ................................................................................................................................................... 9
2.5.2 VCC_IO: IO Supply Voltage (MAX-7)................................................................................................................................... 10
2.5.3 V_BCKP: Backup Supply Voltage ........................................................................................................................................ 10
2.5.4 VDD_USB: USB interface power supply (NEO-7/LEA-7) ......................................................................................................... 10
2.5.5 VCC_RF: Output Voltage RF section.................................................................................................................................... 10
2.5.6 V_ANT: Antenna supply (NEO-7/LEA-7) ............................................................................................................................... 11
2.6 Interfaces ............................................................................................................................................................................... 11
2.6.1 UART ................................................................................................................................................................................ 11
2.6.2 USB ................................................................................................................................................................................... 11
2.6.3 Display Data Channel (DDC) ............................................................................................................................................... 13
2.6.4 SPI (NEO-7) ........................................................................................................................................................................ 13
2.7 I/O pins .................................................................................................................................................................................. 13
2.7.1 RESET_N: Reset input ......................................................................................................................................................... 13
2.7.2 EXTINT: External interrupt .................................................................................................................................................. 13
2.7.3 D_SEL: Interface select (NEO-7)........................................................................................................................................... 14
2.7.4 TX-ready signal .................................................................................................................................................................. 14
2.7.5 ANT_ON: Antenna ON (LNA enable) (NEO-7N, MAX-7Q, MAX-7C) ...................................................................................... 14
2.7.6 Antenna Short circuit detection (LEA-7N, MAX-7W) ............................................................................................................ 14
2.7.7 Antenna open circuit detection .......................................................................................................................................... 14
2.7.8 TIMEPULSE ........................................................................................................................................................................ 14
3 Design ......................................................................................................................... 15
3.1 Design checklist ..................................................................................................................................................................... 15
3.1.1 Schematic checklist ............................................................................................................................................................ 15
3.1.2 Layout checklist ................................................................................................................................................................. 16
3.1.3 Antenna checklist .............................................................................................................................................................. 16
3.2 Design considerations for minimal designs .............................................................................................................................. 16
3.2.1 Minimal design (NEO-7N) ................................................................................................................................................... 17
3.2.2 Minimal design (MAX-7Q) .................................................................................................................................................. 19
3.2.3 Minimal design (LEA-7N) .................................................................................................................................................... 20
3.3 Layout ................................................................................................................................................................................... 21
3.3.1 Footprint and paste mask ................................................................................................................................................... 21
3.3.2 Placement ......................................................................................................................................................................... 22
3.3.3 Antenna connection and ground plane design .................................................................................................................... 23