Navman 30, 20 User Manual

Jupiter 30 / 20

GPS receiver module

Integrator’s Manual

Related documents

•Jupiter Series Development kit guide

LA000645

• Navman NMEA reference manual

MN000315

• SiRF Binary Protocol reference manual

Contents

1.0 Introduction .......................................................................................................4

2.0 Hardware application information................................................................... 4

2.1 Electrical connections (SMT pad interface) .................................................................. 4

2.2 Physical dimensions

2.3 Manufacturing process recommendations ................................................................... 6

2.3.1 Reow recommendations ..................................................................................... 6

2.3.2 Connection pad material ...................................................................................... 6

2.3.3 Solder paste mask size ........................................................................................ 7

2.3.4 Solder paste type ................................................................................................. 7

2.3.5 Coating ................................................................................................................. 7

2.3.6 Post reow washing ............................................................................................. 7

2.3.7 Pre-baking ............................................................................................................ 7

2.3.8 Rework ................................................................................................................. 7

2.4 Typical application circuit ............................................................................................. 7

2.4.1 Power for receiver and active antenna

2.4.2 Grounding ............................................................................................................ 7

2.4.3 Decoupling ........................................................................................................... 8

2.4.4 Serial RS232 data level shifter ............................................................................. 9

2.4.5 External RF lter .................................................................................................. 9

2.5 PCB design recommendations ..................................................................................... 9

2.5.1 Recommended PCB pad layout ........................................................................... 9

2.5.2 General recommendations ................................................................................... 9

2.6 Antenna system design choices

2.6.1 Antenna types

2.6.2 Active antenna ....................................................................................................12

2.6.3 Passive antenna ..................................................................................................13

2.6.4 Jupiter module used as a GPS sensor................................................................13

2.6.5 DC supply protection for an active antenna ........................................................14

2.7 Jupiter adapter printed circuit board ............................................................................16

..................................................................................................... 6

................................................................. 7

..................................................................................12

.....................................................................................................12

3.0 Software application information .................................................................. 17

3.1 Normal mode operation ...............................................................................................17

3.2 Power management

3.2.1 Adaptive TricklePower mode ...............................................................................18

3.2.2 Push-to-Fix mode ...............................................................................................18

3.3 Serial I/O .....................................................................................................................18

3.3.1 Default settings ....................................................................................................18

3.3.2 NMEA input commands ......................................................................................18

3.3.3 Altitude output .....................................................................................................19

3.4 Navman proprietary NMEA low power mode messages

3.4.1 Low power conguration ..................................................................................... 20

3.4.2 Low power acquisition conguration .................................................................. 20

3.5 Control of GPIO connections via serial commands (Jupiter 20) ................................ 20

3.5.1 Congure port directions .....................................................................................21

3.5.2 Set outputs ..........................................................................................................21

3.5.3 Clear outputs .......................................................................................................21

3.5.4 Read inputs .........................................................................................................21

3.6 GPS x output .............................................................................................................21

3.7 Antenna power monitor messages

3.8 Custom application software ...................................................................................... 22

....................................................................................................17

........................................... 20

............................................................................. 22

4.0 Glossary and acronyms .................................................................................23

Figures

Figure 2-1: Lead-free and tin/lead reow prole recommendation ..................................... 6

Figure 2-2: Sample application circuit ................................................................................ 8

Figure 2-3: Recommended application layout dimensions................................................. 9

Figure 2-4: Typical module layout .....................................................................................10

Figure 2-5: Example PCB layout for external active antenna ............................................10

Figure 2-6: PCB microstrip dimensions .............................................................................11

Figure 2-7: Arrangement of active antenna and application board....................................12

Figure 2-8: Cross section of application board with passive patch antenna .....................13

Figure 2-9: Simple current limiter circuit ............................................................................14

Figure 2-10: Active current limit using an IC ......................................................................14

Figure 2-11: Antenna short/open circuit sensor circuit (3.3 V supply only)

........................15

Tables

Table 2-1: Jupiter 30 and Jupiter 20 Module pin functions ................................................. 5

Table 2-2: Summary of pin multi-functionality .................................................................... 6

Table 2-3: Decoupling recommendations ........................................................................... 8

Table 2-4: PCB substrate thicknesses v track width .........................................................11

Table 2-5: Passive and active antenna features ................................................................12

Table 2-6: Recommended antenna characteristics ...........................................................13

Table 2-7: Antenna sense and control functions ...............................................................15

Table 2-8: Connector conguration ...................................................................................17

Table 3-1: Low power modes message values ................................................................ 20

Table 3-2: Low power acquisition input values ................................................................. 20

Table 3-3: Pin conguration of the GPIO lines ..................................................................21

Table 3-4: Antenna status output message values .......................................................... 22

1.0 Introduction

The Navman Jupiter 30 and Jupiter 20 series of GPS receiver modules are complete GPS receivers designed for surface mount assembly (SMT) integration. The modules provide a simple, cost effective GPS solution for application designers. Application integration will vary primarily with respect to antenna system design and EMI protective circuitry.

The Jupiter 30 is the successor to the established Jupiter 20, sharing the same form factor (25.4 x 25.4 mm) and electrical compatibility. This provides a low risk migration path for existing users, offering greater sensitivity, lower power consumption and a faster x.

Fundamental operation requires a 3.3 VDC power supply, approximate current of 80 mA (Jupiter 30) or 100 mA (Jupiter 20), GPS antenna system interface, relevant EMI protection, and the design and layout of a custom PCB.

This document outlines the following design considerations and provides recommended solutions:

Hardware application information

This section introduces the system interface and provides the following physical specications:

a. electrical connections (SMT pad interface)

b. mounting (PCB pad layout dimensions)

c. manufacturing recommendations

d. application circuit interface

It also discusses the fundamental considerations when designing for RF, and presents the antenna system design overview. This covers the following topics:

a. PCB layout

b. antenna system design choices

Software application information

This section provides answers to some common questions that may not have been covered in the above topics.

A sample solution is presented and discussed for example purposes only. Due to the nature and complexity of GPS signals, it is recommended that application integrators adhere to the design considerations and criteria described in this document.

2.0 Hardware application information

The modules provide 30 Surface Mount pads for electrical connections. The sections that follow introduce the physical and relative functional specications for application integration.

Note: The electrical connections can carry very low level GPS signals at 1.57542 GHz. The

layout must be designed appropriately with consideration of the frequencies involved.

2.1 Electrical connections (SMT pad interface)

Details of the module connector conguration are shown in Table 2-1.

Pin No.

Name Type Description

1 PWRIN P main power input (3.3 V)

2 GND P ground

3 BOOT I

serial boot (high for serial boot, low or open circuit for normal operation)

4 RXA I CMOS level asynchronous input for UART A

5 TXA O CMOS level asynchronous output for UART A

6 TXB O CMOS level asynchronous output for UART B

7 RXB I CMOS level asynchronous input for UART B

8 pin 8 multi-functional (see table 2-2)

9 RF_ON O

output to indicate whether the RF section is enabled (active high)

10 GND P ground

11 GND P ground

12 GND P ground

13 GND P ground

14 GND P ground

15 GND P ground

16 GND P ground

RF_IN I RF input

18 GND P ground

19 ACTIVE_PWR P

active power input, 70 mA current limit supply to

this pin

20 VCC_RF O RF Power (+2.85 V) supply output

21 V_BATT P backup battery input

22 NRESET I

external reset (active low), voltage on PIN 22 NRESET must not exceed PWRIN at all times

23 GPS_FIX O GPS x indication (active low)

pins 24-28 multi-functional (see table 2-2)

29 1PPS O 1 pulse per second output

30 GND P ground

Table 2-1: Jupiter 30 and Jupiter 20 Module pin functions

Jupiter 30 Jupiter 20

GPIO Name and Description GPIO

24 13 reserved 6 GPIO (SDO) not connected

25 4 reserved 5 GPIO (SDI) ADC DOut

26 –

27 15

28 1

8 14

push-to-x wakeup (active on +ve edge)

antenna open circuit sensor input (active

active antenna control output

antenna short circuit sensor input (active

WAKEUP

ANT_OC

high)

ANT_CTRL

NANT_SC

low)

7 GPIO (SCK) ADC Clk

15 ANT_OC

1 ANT_CTRL

3 NANT_SC

Standard &

XTrac name

DR function

FWD/REV

fwd/rev input

(low=forward,

high=reverse)

WHEEL_TICKS

wheel tick input

GYRO_IN gyro input

(analogue 0–5 V)

Table 2-2: Summary of pin multi-functionality

GPIO

Note that the Jupiter 20 D (Dead Reckoning) does not support the active antenna supervisory functionality and associated proprietary NMEA status messaging (see section 3.7).

SPI (Jupiter 20 only)

The Jupiter 20 (GSW2) and Jupiter 20 S (XTrac) do not support the SPI. These pins function only as user GPIOs.

The SPI on the Jupiter 20 D is used to control an internal ADC, which interfaces to an

external gyro.

Implementation of the SPI for any other alternative function requires an SDK (Software Development Kit) from SiRF.

2.2 Physical dimensions

The physical dimensions of the Jupiter 30 and Jupiter 20 modules are identical:

length: 25.4 mm ± 0.1 mm width: 25.4 mm ± 0.1 mm thickness: 3.0 mm max

weight: 4.0 g max

2.3 Manufacturing process recommendations

2.3.1 Reow recommendations

For lead based solder pastes, the maximum reow temperature is 225 °C for 10 seconds. For lead-free solder pastes, the maximum reow temperature is 265 °C for 10 seconds. Refer to Figure 2-1.

Figure 2-1: Lead-free and tin/lead reow prole recommendation

2.3.2 Connection pad material

The 30 surface mount connection pads have a base metal of copper with a gold ash nish. This is suitable for a lead free manufacturing process.

2.3.3 Solder paste mask size

This should be adjusted by experimentation according to the customer’s production process requirements. A 1:1 (paste mask:pad size) ratio has been found to be successful.

2.3.4 Solder paste type

The module accepts all commonly used solder pastes. The solder paste can be lead based or lead-free. If a lead-free process is introduced, factors such as circuit board thickness, fabrication complexity, assembly process compatibility, and surface nish should be taken

into consideration.

2.3.5 Coating

The nal PCB may be selectively coated with an acrylic resin, air/oven cured conformal coating, clear lacquer or corresponding method, which gives electrical insulation and sufcient resistance to corrosion.

2.3.6 Post reow washing

It is recommended that a low residue solder paste is used to prevent the need for post reow washing. If a washing process is used, an aqueous wash is not recommended due to the long drying time required and danger of contaminating the ne pitch internal components.

2.3.7 Pre-baking

The modules are delivered on a tape and reel package sealed in an airtight bag. The MSR (Moisture Sensitivity Rating) is 3, therefore they should be loaded and reowed within 168 hours. If the modules are in ambient humidity for longer than this, a pre-baking/drying process will be required.

2.3.8 Rework

Navman recommends that rework and repair is carried out in accordance with the following guidelines:

• IPC-7711 Rework of Electronic Assemblies

• IPC-7721 Repair and Modication of Printed Boards and Electronic Assemblies

Note: Jupiter 30 and Jupiter 20 modules are covered by a 12-month warranty.

2.4 Typical application circuit

The schematic in Figure 2-2 represents a very basic application circuit, with simple interfaces to the module. It is subject to variations depending on application requirements.

Note: Refer to the Jupiter 20 Dead Reckoning Application Note (LA000433) for the Jupiter 20 D

reference design.

2.4.1 Power for receiver and active antenna

The receiver power connection requires a clean 3.3 VDC. Noise on this line may affect the performance of the GPS receiver.

When an active antenna is used, the DC power is fed to it through the antenna coax. This requires the user to apply the antenna DC voltage to pad 19 of the module. A 2.7 V 25 mA supply is made available on pad 20 if the chosen antenna can accept that voltage. This supply is under the command of the TricklePower energy control.

2.4.2 Grounding

Separate AGND (Analogue Ground) and DGND (Digital Ground) grounds are shown in Figure 2-2. If this grounding method is used, the ground planes can be connected underneath the module. In some applications with very small ground planes, separate ground planes may not be required. This should be determined by the application integrator. See Section 2.5.2 for ground plane recommendations and design considerations involving the antenna input and the 50 Ω microstrip connection.

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