Global Sat EB-3531 User manual

EB-3531
Specifications are subject to be changed without notice.
Page 1 of 21
Version 1.2.1
GPS Engine Board
EB-3531
Globalsat Technology Corporation
16F., No. 186, Jian-Yi Road, Chung-Ho City, Taipei Hsien 235, Taiwan
Tel: [phone]/ Fax: [phone]
[e-mail]
www.globalsat.com.tw
USGlobalSat, Inc.
14740 Yorba Court, Chino, CA 91710
Tel: [phone] / Fax: [phone]
[e-mail]
www.usglobalsat.com

EB-3531
Specifications are subject to be changed without notice.
Page 2 of 21
Version 1.2.1
1. Product Information
Product Part I.D. EB-3531
Product Description:
The EB-3531 is a compact, high performance, low power consumption GPS engine board. It
features a SiRF Star III chipset, which can track up to 20 satellites at a time and perform fast
TTFF (time to first fix) in weak signal environments. The EB-3531 is ideal for automotive or
marine navigation, personal positioning, fleet management, and mobile-phone navigation.
Product Features
9SiRF GSC3f/LP high performance GPS Chipset
9Very high sensitivity (Tracking Sensitivity: -159 dBm)
9Extremely fast TTFF (Time To First Fix) at low signal level
9All-in-view 20-channel parallel processing
9Two serial ports
94Mb flash
9Built-in LNA
9Compact size (15mm * 13mm * 2.2mm) suitable for space-sensitive application
9One size component, easy to mount on another PCB board
9Support NMEA 0183 and SiRF binary protocol
9WAAS / EGNOS MSAS support
9RoHS compliant
Product Specifications
GPS Receiver
Chipset SiRF GSC3f/LP
Frequency L1, 1575.42 MHz
Code C/A Code
Protocol NMEA 0183 v3.0
Default:GGA,GSA,GSV,RMC
Support:VTG,GLL,ZDA)
SiRF binary and NMEA Command
Available Baud Rate 4,800 to 57,600 bps adjustable

EB-3531
Specifications are subject to be changed without notice.
Page 3 of 21
Version 1.2.1
Channels 20
Flash 4Mbit
Sensitivity Tracking:-159dBm
Cold Start 42 seconds, average
Warm Start 38 seconds, average
Hot Start 1 second, average
Reacquisition 0.1 second, average
Accuracy Position: 10 meters, 2D RMS
5 meters, 2D RMS, WAAS enabled
Velocity: 0.1 m/s
Time: 1us synchronized to GPS time
Maximum Altitude 18,000 meter
Maximum Velocity 515 meter/second
Maximum Acceleration 4G
Update Rate 1 Hz
DGPS WAAS, EGNOS, MSAS
Datum WGS-84
Interface
I/O Pins 2 serial ports
Physical Characteristic
Type 22-pin stamp holes
Dimensions 15 mm * 13mm * 2.2 mm ±0.2mm
DC Characteristics
Power Supply 3.3Vdc ±5%
Backup Voltage 2.0 ~ 3.6Vdc
Power Consumption Acquisition: 60mA
Tracking: 42mA
Environmental Range
Humidity Range 5% to 95% non-condensing
Operation Temperature -30C to 85C
Storage Temperature -40C to 85C

EB-3531
Specifications are subject to be changed without notice.
Page 4 of 21
Version 1.2.1
2. Technical Information
Block Diagram
Module Pin Assignment

EB-3531
Specifications are subject to be changed without notice.
Page 5 of 21
Version 1.2.1
Pin NO. Pin Name I/O Remark
1. RXB I Serial input (default null)
2. TXB O Serial output (default null)
3. TIMEMARK I/O One pulse per second.
4. TXA O Serial output (default NMEA)
5. RXA I Serial input (default NMEA)
6. NC NC
7. GPIO0 I/O General purpose I/O
8. GPIO1 I/O General purpose I/O
9. RF_PWR CTR RF Power ON/OFF.
10. ON_OFF I Edge triggered soft on/off request. It must be low for normal application.
11. VBAT PWR Backup battery supply voltage
12. VCC PWR Main power supply to the engine board.
13. GPIO13 I/O General purpose I/O
14. GPIO14 I/O General purpose I/O
15. GPIO15 O GPS status output.
16. BOOTSEL I/O Set this pin to high for programming flash.
17. VCC_RF PWR Regulated RF power output.
18. GND G Ground.
19. RF IN RF GPS antenna input.
20. GND G Ground.
21. GND G Ground.
22. GND G Ground.

EB-3531
Specifications are subject to be changed without notice.
Page 6 of 21
Version 1.2.1
Application Circuit
VIN
C3
470PF
GPS_3V3
MS518S-FL35E
BATTERY
12
C6
0.1UF
1 2
A1
GPS_ANTENNA
1
GPS POWER
C1
22UF/10V
L4
BLM18AG121SN1D
D1
RB521S
M1
EB-3531
1
2
3
4
5
21
6
7
8
9
10 11
12
13
14
15
22
16
17
18
19
20
RXB
TXB
1PPS
TXA
RXA
GND
NC
GPIO0
GPIO1
RF_PWR
ON_OFF VBAT
VCC
GPIO13
GPIO14
GPIO15
GND
BOOTSEL
VCC_RF
GND
RF_IN
GND
R6
270R
1 2
U1
XC6209B332MRN 3.3V
1
2
43
5
VIN
GND
NCCE
VOUT
C2
10UF/16V
GPS_3V3
C5
1UF
1 2
L3
BLM18AG121SN1D
GPS_3V3
TXA
C7
10UF
D2
RB512S
RXA
L1
BLM18AG121SN1D
GPS Active Antenna Specifications (Recommendation)
Frequency: 1575.42 + 2MHz
Axial Ratio: 3 dB Typical
Output Impedance: 50
Polarization: RHCP
Amplifier Gain: 18~22dB Typical
Output VSWR: 2.0 Max.
Noise Figure: 2.0 dB Max
Antenna Input Voltage: 2.85V (Typ.)

EB-3531
Specifications are subject to be changed without notice.
Page 7 of 21
Version 1.2.1
Dimensions
Recommend Layout PAD
Tolerances: ±0.1mm

EB-3531
Specifications are subject to be changed without notice.
Page 8 of 21
Version 1.2.1
Application Guideline
Application Circuit
1.
D1
RB521S
GPS_3V3
M1
EB-3531
1
2
3
4
5
21
6
7
8
9
10 11
12
13
14
15
22
16
17
18
19
20
RXB
TXB
1PPS
TXA
RXA
GND
NC
GPIO0
GPIO1
RF_PWR
ON_OFF VBAT
VCC
GPIO13
GPIO14
GPIO15
GND
BOOTSEL
VCC_RF
GND
RF_IN
GND
MS518S-FL35E
BATTER Y
12
R6
270R
1 2
TXA
D2
RB512S
RXA
L3
BLM18AG121SN1D
RF Sw itch
24-20003-12030N
1
2
1
2
50 Ohm Micro strip line
C7
10UF
C5
1UF
1 2
J1_I-PEX connect
External antenna
12
GPS_3V3
C6
0.1UF
1 2
50 Ohm Micro
strip line
L4
BLM18AG121SN1D
2.
VIN
C2
10UF/16V
C3
470PF
U1
XC6209B332MRN 3.3V
1
2
43
5
VIN
GND
NCCE
VOUT
C1
22UF/10V
GPS POWER
GPS_3V3
L1
BLM18AG121SN1D

EB-3531
Specifications are subject to be changed without notice.
Page 9 of 21
Version 1.2.1
Layout Rules
Do not route the other signal or power trace under the engine board.
* RF:
This pin receives signal of GPS analog via external active antenna. It has to be a controlled
impedance trace at 50ohm.
Do not place the RF traces close to the other signal path and not routing it on the top layer.
Keep the RF traces as short as possible.
* Antenna:
Keep the active antenna on the top of your system and confirm the antenna radiation
pattern、axial ratio、power gain、noise figure、VSWR are correct when you Setup the antenna
in your case.
GPS Passive (or Active) Antenna Specifications (Recommendation)
Frequency: 1575.42±2 MHz
Axial Ratio: 3 dB Typical
Output Impedance: 50
Polarization: RHCP
Output VSWR: 1.5 Max.
Active option
Low Noise Amplifier:
Amplifier Gain: 18~22dB Typical
Output VSWR: 2.0 Max.
Noise Figure: 2.0 dB Max.
Antenna Input Voltage: 2.85V Typical

EB-3531
Specifications are subject to be changed without notice.
Page 10 of 21
Version 1.2.1
Design Notes
VCC: This is the main power supply to the engine board. (3.3Vdc ± 5%).
GND: Ground pin for the baseband circuit.
RXA: This is the main channel for receiving software commands from SiRFdemo software or
from your proprietary software.
RXB: For user’s application (default null).
TXA: This is the main channel for transmitting navigation and measurement data to a navigation
software or user written software. Output TTL level, 0V ~ 2.85V.
TXB: For user’s application (default null).
RF_IN: This pin receives signal of GPS analog via external active antenna. It has to be a
controlled impedance trace at 50ohm. Do not have RF traces closed the other signal path and
routing it on the top layer. Keep the RF traces as short as possible.
VBAT: This is the battery backup power input for the SRAM and RTC when main power is
removed. Typically, the current draw is 15uA. Without the external backup battery, the
module/engine board will always execute a cold star after turning on. To achieve the faster
start-up offered by a hot or warm start, a battery backup must be connected. The battery voltage
should be between 2.0v and 3.6v. (NOTE:When not in use this pin must be kept “HIGH” for operation.
From Vcc connect a 470 Ohm resistor in series with a 3.2v Zener diode to Ground. Then, connect the Rx
input to Zener’s cathode to pull the input “HIGH”.)
GPIO: User can use this I/O pin for special functions. (For example, control LED).
BOOTSEL: Set this pin to high for programming flash.
VCC_RF: Provide Active Antenna Power 2.85V.
ON_OFF: Edge triggered soft on/off request. It must be low for normal application.
GPIO15: GPS status output. You can connect it to an LED.
Tracking:
Fixing: Hi
RF_PWR_CTRL: RF power ON/OFF control. Hi: RF Power ON. Low: RF Power OFF.

EB-3531
Specifications are subject to be changed without notice.
Page 11 of 21
Version 1.2.1
Demo Kit Test Description
Connect J2 of the demo kit (Male) to J5 of the Test Board (Female) as the diagram below.
Pin Assignment

EB-3531
Specifications are subject to be changed without notice.
Page 12 of 21
Version 1.2.1
J2
Pin Signal Name Pin Signal Name
1 NC 2 VCC
3 NC 4 VCC
5 NC 6 NC
7 NC 8 NC
9 NC 10 GND
11 TXA 12 RXA
13 GND 14 TXB
15 RXB 16 GND
17 NC 18 GND
19 NC 20 NC
J3
Pin Signal Name Pin Signal Name
1 TIMEMARK 2 VCC_RF
3 NC 4 GPIO15
5 GPIO0 6 GPIO14
7 GPIO1 8 GPIO13
9 RF_PWR 10 NC
11 NC 12 NC
13 NC 14 NC
15 NC 16 NC
17 NC 18 NC
19 NC 20 NC
JP1: VBAT

EB-3531
Specifications are subject to be changed without notice.
Page 13 of 21
Version 1.2.1
Test Software (GPSinfo)
1. Select COM Port & Baud Rate
2. Press Start GPS
3. Software Commands
NMEA Output Command
GGA-Global Positioning System Fixed Data
Table B-2 contains the values for the following example:
$GPGGA,161229.487,3723.2475,N,12158.3416,W,1,07,1.0,9.0,M,,,,0000*18
Table B-2 GGA Data Format
Name Example Units Description
Message ID $GPGGA GGA protocol header
UTC Time 161229.487 hhmmss.sss
Latitude 3723.2475 ddmm.mmmm
N/S Indicator N N=north or S=south

EB-3531
Specifications are subject to be changed without notice.
Page 14 of 21
Version 1.2.1
Longitude 12158.3416 dddmm.mmmm
E/W Indicator W E=east or W=west
Position Fix Indicator 1 See Table B-3
Satellites Used 07 Range 0 to 12
HDOP 1.0 Horizontal Dilution of Precision
MSL Altitude19.0 meters
Units M meters
Geoid Separation1meters
Units M meters
Age of Diff. Corr. second Null fields when DGPS is not used
Diff. Ref. Station ID 0000
Checksum *18
<CR><LF> End of message termination
SiRF Technology Inc. does not support geoid corrections. Values are WGS84 ellipsoid heights.
Table B-3 Position Fix Indicator
Value Description
0 Fix not available or invalid
1 GPS SPS Mode, fix valid
2 Differential GPS, SPS Mode , fix valid
3 GPS PPS Mode, fix valid
GLL-Geographic Position-Latitude/Longitude
Table B-4 contains the values for the following example:
$GPGLL,3723.2475,N,12158.3416,W,161229.487,A*2C
Table B-4 GLL Data Format
Name Example Units Description
Message ID $GPGLL GLL protocol header
Latitude 3723.2475 ddmm.mmmm
N/S Indicator n N=north or S=south
Longitude 12158.3416 dddmm.mmmm
E/W Indicator W E=east or W=west
UTC Position 161229.487 hhmmss.sss
Status A A=data valid or V=data not valid
Checksum *2C
<CR><LF> End of message termination
GSA-GNSS DOP and Active Satellites

EB-3531
Specifications are subject to be changed without notice.
Page 15 of 21
Version 1.2.1
Table B-5 contains the values for the following example:
$GPGSA,A,3,07,02,26,27,09,04,15,,,,,,1.8,1.0,1.5*33
TableB-5GSADataFormat
Name Example Units Description
Message ID $GPGSA GSA protocol header
Mode1 A See Table B-6
Mode2 3 See Table B-7
Satellite Used107 Sv on Channel 1
Satellite Used102 Sv on Channel 2
.
Satellite Used1Sv on Channel 12
PDOP 1.8 Position dilution of Precision
HDOP 1.0 Horizontal dilution of Precision
VDOP 1.5 Vertical dilution of Precision
Checksum *33
<CR><LF> End of message termination
1. Satellite used in solution.
TableB-6Mode1
Value Description
M Manual-forced to operate in 2D or 3D mode
A 2D automatic-allowed to automatically switch 2D/3D
TableB-7Mode2
Value Description
1 Fix Not Available
2 2D
3 3D
GSV-GNSS Satellites in View
Table B-8 contains the values for the following example:
$GPGSV,2,1,07,07,79,048,42,02,51,062,43,26,36,256,42,27,27,138,42*71
$GPGSV,2,2,07,09,23,313,42,04,19,159,41,15,12,041,42*41
TableB-8GSVDataFormat
Name Example Units Description
Message ID $GPGSV GSV protocol header
Number of Messages12 Range 1 to 3
Message Number11 Range 1 to 3

EB-3531
Specifications are subject to be changed without notice.
Page 16 of 21
Version 1.2.1
Satellites in View 07
Satellite ID 07 Channel 1(Range 1 to 32)
Elevation 79 degrees Channel 1(Maximum90)
Azimuth 048 degrees Channel 1(True, Range 0 to 3
5
SNR(C/No) 42 dBHz Range 0 to 99,null when not tr
a
……. …….
Satellite ID 27 Channel 4 (Range 1 to 32)
Elevation 27 Degrees Channel 4(Maximum90)
Azimuth 138 Degrees Channel 4(True, Range 0 to 3
5
SNR(C/No) 42 dBHz Range 0 to 99,null when not tr
a
Checksum *71
<CR><LF> End of message termination
Depending on the number of satellites tracked multiple messages of GSV data may be required.
RMC-Recommended Minimum Specific GNSS Data
Table B-9 contains the values for the following example:
$GPRMC,161229.487,A,3723.2475,N,12158.3416,W,0.13,309.62,120598,,*10
Table B-9 RMC Data Format
Name Example Units Description
Message ID $GPRMC RMC protocol header
UTC Time 161229.487 hhmmss.sss
Status A A=data valid or V=data not valid
Latitude 3723.2475 ddmm.mmmm
N/S Indicator N N=north or S=south
Longitude 12158.3416 dddmm.mmmm
E/W Indicator W E=east or W=west
Speed Over Ground 0.13 knots
Course Over Ground 309.62 degrees True
Date 120598 ddmmyy
Magnetic Variation2degrees E=east or W=west
Checksum *10
<CR><LF> End of message termination
SiRF Technology Inc. does not support magnetic declination. All “course over ground” data are
Geodetic WGS48 directions.
VTG-Course Over Ground and Ground Speed
$GPVTG,309.62,T,,M,0.13,N,0.2,K*6E
Table B-9 VTG Data Format
Name Example Units Description
Message ID $GPVTG VTG protocol header

EB-3531
Specifications are subject to be changed without notice.
Page 17 of 21
Version 1.2.1
Course 309.62 degrees Measured heading
Reference T True
Course degrees Measured heading
Reference M Magnetic
Speed 0.13 knots Measured horizontal speed
Units N Knots
Speed 0.2 Km/hr Measured horizontal speed
Units K Kilometers per hour
Checksum *6E
<CR><LF> End of message termination
■NMEA Input Command
A.) Set Serial Port ID:100 Set PORTA parameters and protocol
This command message is used to set the protocol (SiRF Binary, NMEA, or USER1) and/or
the communication parameters (baud, data bits, stop bits, parity). Generally, this command
is utilize to switch the GPS module back to SiRF Binary protocol mode, where an extensive
message commands are readily available. In example, whenever users are interested in
altering navigation parameters, a valid message sent and is receive by the recipient module,
the new parameters will be stored in battery backed SRAM and then the receiver will restart
using the saved parameters.
Format:
$PSRF100,<protocol>,<baud>,<DataBits>,<StopBits>,<Parity>*CKSUM
<CR><LF>
<protocol> 0=SiRF Binary, 1=NMEA, 4=USER1
<baud> 1200, 2400, 4800, 9600, 19200, 38400
<DataBits> 8,7. Note that SiRF protocol is only valid f8 Data bits
<StopBits> 0,1
<Parity> 0=None, 1=Odd, 2=Even
Example 1: Switch to SiRF Binary protocol at 9600,8,N,1
$PSRF100,0,9600,8,1,0*0C<CR><LF>
Example 2: Switch to User1 protocol at 38400,8,N,1
$PSRF100,4,38400,8,1,0*38<CR><LF>
**Checksum Field: The absolute value calculated by exclusive-OR the 8 data bits of each
character in the Sentence, between, but, excluding “$” and “*”. The hexadecimal value of the
most significant and least significant 4 bits of the result are converted to two ASCII characters

EB-3531
Specifications are subject to be changed without notice.
Page 18 of 21
Version 1.2.1
(0-9,A-F) for transmission. First, the most significant character is transmitted.
**<CR><LF> : Hex 0D 0A
B.) Navigation initialization ID:101 Parameters required for start
This command is used to initialize the GPS module for a “Warm” start, by providing real-time position
（in X, Y, Z coordinates), clock offset, and time. This action enables the GPS receiver to search for the
necessary satellite signals at the correct signal parameters. The newly acquired and stored satellite
data will enable the receiver to acquire signals more quickly, and thus, generate a rapid navigational
solution.
When a valid Navigation Initialization command is receive, the receiver will restart using the input
parameters as a basis for satellite selection and acquisition.
Format
$PSRF101,<X>,<Y>,<Z>,<ClkOffset>,<TimeOfWeek>,<WeekNo>,<chnlCount>,<ResetCfg>
*CKSUM<CR><LF>
<X> X coordinate position
INT32
<Y> Y coordinate position
INT32
<Z> Z coordinate position
INT32
<ClkOffset> Clock offset of the receiver in Hz, Use 0 for last saved value if available.
If this is unavailable, a default value of 75000 for GSP1, 95000 for GSP 1/LX
is used.
INT32
<TimeOf Week> GPS Time Of Week
UINT32
<WeekNo> GPSWeekNumber
UINT16
Week No and Time Of Week calculation from UTC time
<chnlCount> Number of channels to use.1-12. If your CPU throughput is not high enough,
you could decrease needed throughput by reducing the number of active
channels
UBYTE
<ResetCfg> bitmask
0×01=Data Valid warm/hotstarts=1
0×02=clear ephemeris warm start=1
0×04=clearmemory.Coldstart=1
UBYTE
Example: Start using known position and time.
$PSRF101,-2686700,-4304200,3851624,96000,497260,921,12,3*7F
C.) Set DGPS Port ID:102 Set PORT B parameters for DGPS input

EB-3531
Specifications are subject to be changed without notice.
Page 19 of 21
Version 1.2.1
This command is used to control Serial Port B, an input serial only port used to receive RTCM
differential corrections. Differential receivers may output corrections using different communication
parameters. The default communication parameters for PORT B are set for 9600 Baud, 8data bits, 0
stop bits, and no parity. If a DGPS receiver is used which has different communication parameters,
use this command to allow the receiver decode data correctly. When a valid message is received, the
parameters are stored in a battery backed SRAM. Resulting, GPS receiver using the saved
Parameters for restart.
Format:
$PSRF102,<Baud>,<DataBits>,<StopBits>,<Parity>*CKSUM<CR><LF>
<baud> 1200,2400,4800,9600,19200,38400
<DataBits> 8
<StopBits> 0,1
<Parity> 0=None,Odd=1,Even=2
Example: Set DGPS Port to be 9600,8,N,1
$PSRF102,9600,8,1.0*12
D.) Query/Rate Control ID:103 Query standard NMEA message and/or set output rate
This command is used to control standard NMEA data output messages: GGA, GLL, GSA, GSV, RMC,
and VTG. Using this command message, standard NMEA message is polled once, or setup for
periodic output. In addition, checksums may also be enable or disable contingent on receiving
program requirements. NMEA message settings are stored in a battery-backed memory for each entry
when the message is accepted.
Format:
$PSRF103,<msg>,<mode>,<rate>,<cksumEnable>*CKSUM<CR><LF>
<msg> 0=GGA,1=GLL,2=GSA,3=GSV,4=RMC,5=VTG
<mode> 0=SetRate,1=Query
<rate> Output every <rate>seconds, off=0,max=255
<cksumEnable> 0=disable Checksum,1=Enable checksum for specified message
Example 1: Query the GGA message with checksum enabled
$PSRF103,00,01,00,01*25
Example 2: Enable VTG message for a 1Hz constant output with checksum enabled
$PSRF103,05,00,01,01*20
Example 3: Disable VTG message
$PSRF103,05,00,00,01*21
E.) LLA Navigation initialization ID:104 Parameters required to start using Lat/Lon/Alt
This command is used to initialize the GPS module for a “Warm” start, providing real-time position
(Latitude, Longitude, Altitude coordinates), clock offset, and time. This action enables the GPS
receiver to search for the necessary satellite signals at the correct signal parameters. The newly

EB-3531
Specifications are subject to be changed without notice.
Page 20 of 21
Version 1.2.1
acquired and stored satellite data will enable the receiver to acquire signals more quickly, and thus,
generate a rapid navigational solution.
When a valid LLA Navigation Initialization command is receive, then the receiver will restart using the
input parameters as a basis for satellite selection and acquisition.
Format:
$PSRF104,<Lat>,<Lon>,<Alt>,<ClkOffset>,<TimeOfWeek>,<WeekNo>,
<ChannelCount>, <ResetCfg>*CKSUM<CR><LF>
<Lat> Latitude position, assumed positive north of equator and negative
south of equator float, possibly signed
<Lon> Longitude position, it is assumed positive east of Greenwich
and negative west of Greenwich Float, possibly signed
<Alt> Altitude position float, possibly signed
<ClkOffset> Clock Offset of the receiver in Hz, use 0 for last saved value if
available.
If this is unavailable, a default value of 75000 for GSP1, 95000 for GSP1/LX
is used.
INT32
<TimeOfWeek> GPS Time Of Week
UINT32
<WeekNo> GPSWeekNumber
UINT16
<ChannelCount> Number of channels to use. 1-12
UBYTE
<ResetCfg> bit mask
0×01=Data Valid warm/hot starts=1
0×02=clear ephemeris warm start=1
0×04=clearmemory.Coldstart=1
UBYTE
Example: Start using known position and time.
$PSRF104,37.3875111,-121.97232,0,96000,237759,922,12,3*37
F.) Development Data On/Off ID:105 Switch Development Data Messages On/Off
Use this command to enable development debug information if you are having trouble in attaining
commands accepted. Invalid commands will generate debug information that should enable the user
to determine the source of the command rejection. Common input rejection problems are associated
to invalid checksum or parameter out of specified range. Note, this setting is not preserved across a
module reset.
Format: $PSRF105,<debug>*CKSUM<CR><LF>
<debug> 0=Off,1=On
Example: Debug On $PSRF105,1*3E