4037735105393 - Global Navigation Systems

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

1 INTRODUCTION

GNS302uLP is a complete GPS receiver that is optimized for very low power consumption. Thanks

to an advanced dynamic power management technology, the current is reduced to a minimum of

~7 mA (<25mW). Average power savings in comparison with common low power GPS modules are

60%.

Unlike other concepts that use trickle operation modes with reduced update rates of the position,

GNS302uLP works at full 1-per-second position update rate.

Best power savings can be achieved in typical outdoor scenarios with wide view angles to the sky.

GNS 302uLP allows long term tracking in small applications like fitness wearables, pet tracking and

camera applications.

Very low power requirements and internal voltage regulator makes it easy to run the receiver with

various power supplies and allows direct connection to LiIon batteries.

For high accuracy and additional SBAS operation, the GNS302uLP can be switched to continous

high activity power mode by software command.

GNS 302uLP utilizes a tiny chip antenna to realize high sensitivity with very small space

requirements.

If radiation pattern and best antenna performance is a main requirement, GNS also offers a patch

antenna version (GNS601uLP).

Its attractive price and ready-to run configuration with integrated antenna solution reduces time-to-

market to a minimum.

First Fixes after just a few seconds are achieved with the help of A-GPS using EPOTM (Extended

Prediction Orbit) and the EASYTM self generated orbit prediction algorithm. EASYTM (Embedded Assist

System) does not require any resources from the host and no data from the network.

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

AlwaysLocateTM power management feature can be activated to further lower the power

requirements at lower update rates. It adaptively adjusts power consumption depending on the

environment and motion conditions, in order to achive a balance between fix rate, power

consumption and position accuracy.

GNS302uLP offers the industry’s highest level of navigation sensitivity up to -165dBm1. It has

superior dynamic performance at high velocity and provides effective protection against

interference signals using MTAICTM ( Multi-tone active interference canceller). Up to 12 independent

channel interference continious wave jammers <-80dBm can be eliminated or reduced.

The embedded logger function LOCUS with a 16-hrs (8000 samples) on chip memory makes this

GPS module a complete track logger for many applications.

In professional timing applications the outstanding high accuracy PPS (pulse per second) hardware

pin is used for synchronization to GPS second. Typical accuracy is 10ns RMS.

Features

 Ultra low power technology at full tracking output rate

 66 acquisition-/ 22 tracking channels

 Ultra high tracking/navigation sensitivity: -165dBm1

 tuned ceramic chip antenna

 SBAS (WAAS,EGNOS,MSAS,GAGAN, QZSS) correction support in high activity mode

 A-GPS by EPO “Extended Prediction Orbit” TM enables 7/14days prediction

 12 Multitone Active Interference Canceller (MTAIC) for GPS-in-band jammer rejection

 EASY TM : 3 day self generated orbit prediction support

 High accuracy 1PPS output

 NMEA-0183 protocol, configurable

 High update rate (up to 10/s) in high activity mode

 Embedded logger function with 16hrs internal memory

 GPS current consumption (@3.3V):

Acquisition: 22mA typical

Tracking: 7mA typical

 Low backup current consumption 7uA, typical

 SMD type LGA

 Small form factor: 15.7x10x2.0mm

1 Note: Measured navigation sensitivity at RF input of chipset

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

2 INDEX

1 INTRODUCTION ----------------------------------------------------------------------------------------- 1

2 INDEX --------------------------------------------------------------------------------------------------- 3

3 FUNCTIONAL DESCRIPTION ---------------------------------------------------------------------------- 4

3.1 System description --------------------------------------------------------------------------------------------------------- 4

3.2 Block diagram -------------------------------------------------------------------------------------------------------------- 4

3.3 Power Management Features ---------------------------------------------------------------------------------------------- 5

3.4 EASYTM self generated prediction data feature ---------------------------------------------------------------------------- 7

3.5 Pulse Per Second (PPS) ---------------------------------------------------------------------------------------------------- 8

3.6 Logger function ------------------------------------------------------------------------------------------------------------- 8

3.7 Active interference cancellation (MTAIC) --------------------------------------------------------------------------------- 9

3.8 SBAS (Satellite Based Augmentation) support --------------------------------------------------------------------------- 9

3.9 GPS almanac and ephemeris data----------------------------------------------------------------------------------------- 9

3.10 Real time clock (RTC) ------------------------------------------------------------------------------------------------------ 9

3.11 UART interface ------------------------------------------------------------------------------------------------------------ 10

3.12 Module default settings -------------------------------------------------------------------------------------------------- 10

4 TYPICAL APPLICATION BLOCK DIAGRAM ------------------------------------------------------------ 11

4.1 Typical System Overview ------------------------------------------------------------------------------------------------ 11

5 GPS characteristics ----------------------------------------------------------------------------------- 12

5.1 GPS characteristics ------------------------------------------------------------------------------------------------------- 12

6 ELECTRICAL SPECIFICATION ------------------------------------------------------------------------- 13

6.1 Absolute Maximum Ratings ---------------------------------------------------------------------------------------------- 13

6.2 Electrical characteristics ------------------------------------------------------------------------------------------------- 13

7 PIN CONFIGURATION --------------------------------------------------------------------------------- 14

8 NMEA DATA interface --------------------------------------------------------------------------------- 16

8.1 NMEA output sentences -------------------------------------------------------------------------------------------------- 16

8.2 NMEA command interface------------------------------------------------------------------------------------------------ 16

9 PHYSICAL DIMENSIONS ------------------------------------------------------------------------------ 17

10 RECOMMENDED PAD LAYOUT ----------------------------------------------------------------------- 18

11 DESIGN GUIDELINES -------------------------------------------------------------------------------- 19

11.1 PCB LAYOUT GUIDELINES ----------------------------------------------------------------------------------------------- 19

12 NMEA DATA interface -------------------------------------------------------------------------------- 21

12.1 NMEA output sentences -------------------------------------------------------------------------------------------------- 21

12.2 NMEA command interface------------------------------------------------------------------------------------------------ 21

13 MATERIAL INFORMATION --------------------------------------------------------------------------- 22

14 RECOMMENDED SOLDERING REFLOW PROFILE --------------------------------------------------- 22

15 PACKAGE INFORMATION ---------------------------------------------------------------------------- 23

15.1 TAPE ----------------------------------------------------------------------------------------------------------------------- 23

15.2 REEL ----------------------------------------------------------------------------------------------------------------------- 24

16 ORDERING INFORMATION -------------------------------------------------------------------------- 25

17 ENVIRONMENTAL INFORMATION ------------------------------------------------------------------- 25

18 MOISTURE SENSITIVITY ---------------------------------------------------------------------------- 26

19 DOCUMENT REVISION HISTORY -------------------------------------------------------------------- 26

20 RELATED DOCUMENTS ------------------------------------------------------------------------------ 26

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

3 FUNCTIONAL DESCRIPTION

3.1 System description

The GNS302uLP is a high performance, ultra low power GPS receiver that includes an integrated RF

frontend (SAW Filter + LNA) and a ceramic chip antenna.

Due to high input sensitivity and low noise amplifier (LNA), it can work at weak GPS signals.

GNS302uLP is a complete autonomous GPS receiver, including:

- Full GPS processing, without any host processing requirements

- Standard NMEA message output

- A powerful NMEA command and control interface

- All clock sources integrated

- RF frontend integrates a two stage low noise amplifier (LNA) a SAW filter and a high

performance chip antenna

- Interface for UART, PPS output pin, Fix Status Indicator pin

3.2 Block diagram

GPS chip

32.768kHz

crystal

26MHz

TCXO

SAW filter

+Low Noise

Amplifier

GND

1,5,6,15,16,20

VCC

GPS chip

antenna

VBACKUP

3D-Fix

1PPS

TXA

RXA

RXB

WAKEUP

RESET

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

3.3 Power Management Features

GNS302uLP uses an advanced hardware / firmware architecture to minimize power consumption at

full navigation update rate of 1position per second.

Best savings are possible with 6 SVs in track and good fieldstrength.

 uLP feature is a dynamic power management that allows to reduce the power consumption

to ~40% in average. Thanks to advanced hardware and firmware architecture and unlike

other power management features, uLP feature will calculate and output position data every

second. uLP feature has been developed for fitness- and other wearable applications. The

average accuracy will be slightly reduced (4m instead of 3m). For static or slow moving

scenarios , the savings can be better than 70%. uLP feature is activated by default and can

be deactivated through $PMTK262,0 command.

Besides of the uLP power mode, the well known power savings modes with reduced output rate and

performance are available when uLP is disabled.

Power management schemes implemented for any GPS system requires an optimally tuned

performance for both accuracy of the position fixes and the average power consumed for best user

experience. GNS302uLP architecture achieves these both aspects by providing flexibility and

design choices for the system integration, based on wide range of use cases and by leveraging on

the proven silicon methodologies. Also GNS302uLP provides position, velocity and time

measurements without any host loading. This, coupled with the optional built-in power

management options, reduces the overall system power budget.

Selectable Power management features:

 In Standby mode RF frontend and internal MPU are switched to deep sleep state. Power

consumption is reduced.This state can be entered by sending the NMEA command:

$PMTK161,0*28<CR><LF>.

Leaving standby mode and resuming to normal operation will be managed by sending any

byte to the module.

 Backup mode can be entered by sending NMEA command: $PMTK225,4*2F<CR><LF>.

The GPS core will shut down autonomously to backup state, Vcc supply can now be switched

off by an external power supply switch.

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

 Periodic mode describes a power mode, which will autonomously power on/off the module

in programmable time slots with reduced fix rate. Periodic mode is useful during stationary

operation or if position fixes are just needed from time to time. Since power consumption in

GPS off times is nearly zero, the power consumption in periodic mode can be estimated by

Ptracking * (ton/(ton+toff)).

Periodic mode is controlled with NMEA command $PTMK225. See document

NMEAcommandInterface manual for programming details.

 AlwaysLocateTM feature provides an optimized overall GPS system power consumption in

tracking mode under open sky conditions. Always Locate is an intelligent control of periodic

mode. Depending on the environment and motion conditions, GNS302uLP can adjust the

on/off time to achieve balance of positioning accuracy and power consumption. The best

power saving will be made under good reception in stationary mode. Critical reception

conditions and dynamic movements will need full activity of the GPS engine which causes

nominal power requirements (20mA typ in tracking mode).

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

3.4 EASYTM self generated prediction data feature

GNS302uLP includes an internal prediction system, that allows to sample satellite orbit data during

operation and use that data to speed up TTFF on later starts.The prediction time frame is up to

three days forward.

Although this prediction feature does not provide the very short TTFF that is achieved using AGPS,

it can help to find a fix solution faster and in weak signal condition scenario. Prediction data will be

kept in memory as long as VBACKUP is present. This option is activated by default.

Note: The EASY functionality is only supported, if “VBACKUP” pin is conntected and the NMEA update

rate is 1Hz.

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

3.5 Pulse Per Second (PPS)

GNS302uLP provides a Pulse Per Second (PPS) hardware output pin for timing purposes. After

calculation of a 3D position fix (default setting), the PPS signal is accurately aligned to the GPS

second boundaries. The pulse generated is approximately 100 milliseconds in duration and the

repetition rate is 1 second. On request PPS output can activated on a 2D- fix or after power-up of

the module, providing a time accuracy decreased PPS signal.

GNS302uLP module provides an exceptionally low RMS jitter of typical 10 nanoseconds.

PPS characteristics based upon a 3D-fix

1PPS pulse duration

100

msec

1PPS time jitter

nsec

RMS

Pulse rising edge deviation from

expected pulse time, measured

with full 3D fix

1PPS rise and fall time

nsec

10%..90%, load is 10k||5pF

3.6 Logger function

GNS302uLP provides an autonomous logger function that automatically stores position information

in an internal 128kB flash memory. A complete tracking unit can be realized without any external

CPU or memory.

The parameters for logging are programmable via the NMEA command interface. The following

parameter can be set to optimize logging time:

- logger rate

The commands for logger include:

- start logging

- stop logging

- erase memory

- readout memory

please refer to the NMEAcommandInterface manual for details.

T1 = 100ms

T2 = 1sec

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

3.7 Active interference cancellation (MTAIC)

Because different wireless technologies like Wi-Fi, GSM/GPRS, 3G/4G, Bluetooth are integrated into

portable systems, the harmonic of RF signals may influence the GPS reception.

The multi-tone active interference canceller can reject external RF interference which come from

other active components on the main board, thus improving the performance of GPS reception.

GNS302uLP can cancel up to 12 independent continuous wave (CW) channels having signal levels

of up to -80dBm. The functionality is enabled by default and increases power consumption by about

1mA.

3.8 SBAS (Satellite Based Augmentation) support

GNS302uLP supports Satellite Based Augmentation for improvement of the navigation precision.

Correction data is sent from geostationary satellites to the GPS receiver. GNS302uLP supports

European, US, and Asian augmentation systems (EGNOS, WAAS, GAGAN, MSAS, QZSS) to enable

precision improvements in nearly every region of the world.

SBAS is active by default and will automatically track the available SBAS satellites. It can be

disabled by NMEA command. See document NMEAcommandInterface manual for details.

Note: SBAS is deactivated in uLP mode. For SBAS activation, uLP mode must be disabled

3.9 GPS almanac and ephemeris data

For quick re-acquisition of the GPS after off-times, the GPS engine should have access to almanac

and ephemeris data. This data is permanently stored inside GNS302uLP module, even if all power

supplies have been removed. When the GPS is powered-up again, the data will be used to allow a

quick re-acquisition, as soon as a coarse time information is available. Time will be available

immediately, when RTC is kept running.

3.10 Real time clock (RTC)

GNS302uLP has a real time clock with 32,768Hz crystal onboard. As long as VBACKUP is connected to

a power source, the real time clock and the module memory can be kept alive at very low power

consumption of just 7uA. The RTC will track the current time and enable the module to start from

sleep states with very fast time to first Fix (TTFF).

Internal Logger Function

Logger data rate

1/15

1/s

Logger data memory

128

kBytes

Flash memory

Logger trigger

programm

able

Logger can be triggered on

various events

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

3.11 UART interface

GNS302uLP core and I/O sections work at 3.3V nominal. Absolute Maximum Ratings should not be

exceeded. Should the GNS302uLP be interfaced to a host with I/O at higher/lower levels, level

shifters should be used. UART baud rate is 9600 baud by default. The baud rate can be modified to

higher rates by a NMEA software command. See document NMEAcommandInterface manual for

details.

GPS UART Default Settings

Parameter

Value

Baud rate

9600 fixed

Data length

8 bits

Stop bit

Parity

None

3.12 Module default settings

The GNS302uLP receiver comes with default settings, which are persistently programmed.

Whenever power is removed from the module (both VCC and VBACKUP), the settings will be reset

to the values shown in the following table.

NMEA output sentences

Setting

Default value

UART setting

9600,8,N,1

Fix frequency (update rate)

1/sec

NMEA sentences

$GPRMC,$GPGSA,$GPGSV,$GPGGA

NMEA rate

Once a second

Self survey prediction mode:

EASYTM

enabled

Active interference

cancellation:MTAIC

enabled

Datum

WGS 84

Logging parameters

Wrap when full / Content Basic / Interval 15 sec

uLPower Feature

Activated (disabled on request)

Elevation mask

5°

On request, other options can be selected as preprogrammed (persistent default) options.

Please contact the GNS support for your project requirements.

Note : Customized options are solely available for fixed order lots.

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

4 TYPICAL APPLICATION BLOCK DIAGRAM

4.1 Typical System Overview

Host Processor

MMI

(keys, display)

Power

Management

2.8 to 4.3V

GNS

302uLP

UART RX

UART TX

VCC

V Backup

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

5 GPS characteristics

5.1 GPS characteristics

Parameter

Min

Typ

Max

Unit

Note

general

Frequency

1575.42

MHz

GPS L1 C/A code

SBAS

WAAS,EGNOS,MSAS,GAGAN,QZSS1

Datum

WGS84

AGPS

days

Configurable

Output data frequency

1/10

1/sec

1/s in uLP mode

Navigation&tracking sensitivity1

-165

dBm

autonomous

Acquisition sensitivity1

-148

dBm

Cold start

Reacquisition sensitivity1

-163

dBm

Hot start

TTFF hotstart

sec

6 SVs @-130dBm

TTFF autonomous warm start

sec

6 SVs @-130dBm

TTFF autonomous warm start

5..10

sec

6 SVs @-130dBm / with EASY on

TTFF autonomous cold start

sec

6 SVs @-130dBm

Reacquisition time

sec

6 SVs @-130dBm

Number of channels tracking

Number of acquisition channels

Dimension

15.7x10x2

Tolerance is 0.2 mm

Weight

0.64

Note:

1) Only available when uLP mode is disabled

Accuracy

Position error (50%CEP)

2D-RMS

Position error (50%CEP)

2.5

Using (SBAS) , uLP mode disabled

Velocity error

0.1

m/s

velocity error

0.05

m/s

Using (SBAS) , uLP mode disabled

Antenna specifications

Frequency

1575.42

MHz

VSWR

f = 1575.4 MHz

gain

3.2

peak@zenith , f = 1575.4 MHz

impedance

Ohm

f = 1575.4 MHz

Polarization

Linear

ITAR limits

Operation altitude

18,000

Operation velocity

515

m/s

Operation acceleration

1 note: based on chip specifications

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

6 ELECTRICAL SPECIFICATION

6.1 Absolute Maximum Ratings

Parameter

Value

Unit

Supply voltage: Vcc

–0.5 to 4.3

Backup voltage: VBACKUP

–0.5 to 4.3

Input voltage to analog pins

–0.5 to 3.3

Input voltage to all other pins

–0.5 to Vcc

Operating ambient temperature range

–40 to +85

°C

Storage temperature range

–50 to +125

°C

6.2 Electrical characteristics

Parameter

Min

Typ

Max

Unit

Note

Vcc

2.8

3.3

4.3

supply voltage

Vcc ripple voltage

mVpp

VBACKUP

2.0

3.0

4.3

Backup voltage for RTC and

memory retention, must be

available during normal

operation

High level output voltage VOH

2.38

2.9

Low level output voltage VOL

0.42

High-level input voltage VIH

2.1

3.5

Low-level input voltage VIL

-0.3

0.7

Operating temperature

-40

°C

Full specified sensitivity

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

7 PIN CONFIGURATION

Top View

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

Name

I/O

Description & Note

GND

Ground

WAKEUP

Wakeup input (TBD) leave open

Not conected

3D_FIX

3D-Fix Indicator

The 3D_FIX is assigned as a fix flag output. If not used, keep floating.

Before 2D Fix

The pin will continuously toggle with 1 Hz. output 100ms high-level and 0.9s low-level signal

After 2D or 3D Fix

The pin will continuously output low-level signal

This pin may not connected to high-level at power-on sequence.

GND

Ground

GND

Ground

RXA

Serial Data Input A for NMEA commands (TTL)

This is the UART-A receiver of the module. It is used to receive commands from system

TXA

Serial Data Output A for NMEA output (TTL)

This is the UART-A transmitter of the module. It outputs GPS information for application.

RXB

Serial Data Input B

This is the UART-B receiver of the module. It is used to receive RTCM data from system

Not connected

1PPS

1PPS Time Mark Output 2.8V CMOS Level

This pin provides one pulse-per-second output from the module and synchronizes to GPS time. Keep floating if

not used.

Not conected

VBACKUP

Backup power input for RTC & navigation data keep

This connects to the backup power of the GPS module. Power source (such as battery) connected to this pin will

help the GPS chipset in keeping its internal RTC running when the main power source is turned off. The voltage

should be kept between 2.8V~4.3V, Typical 3.3V.

If VBACKUP power was not reserved, the GPS receiver will perform a lengthy cold start every time it is powered-on

because previous satellite information is not retained and needs to be re-transmitted.

This pin must be connected for normal operation.

VCC

Main DC power input

The main DC power supply for the module. The voltage should be kept between from 2.8V to 4.3V. The ripple

must be limited under 50mVpp (Typical: 3.3V).

GND

Ground

GND

Ground

Not conected

RESET

System reset pin

An external reset applied to this pin overrides all other internal controls. RESET# is an active low signal. Pulling

this pin low for at least 20 μs causes a system reset.

GND

Ground

(1) I = INPUT; O = OUTPUT; I/O = BIDIRECTIONAL; P = POWER PIN; ANA = ANALOG PIN.

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

8 NMEA DATA interface

GNS302uLP provides NMEA (National Marine Electronics Association) 0183 compatible data.

A set of proprietary NMEA commands are available to send control messages to the module.

These commands are described in a separate document: NMEA_Interface_manual_MTK_Vx manual.

For standard operation, no commands are needed; the module will start outputting NMEA sentences

after power supply has been attached. GNS302uLP will always start communication output with

9600 bit per second.

If non standard options are needed (f.e. other baud rate , other NMEA sequence) they can be

programmed from host controller during runtime.

Important note : options set by using NMEA command interface are not persistent! They will be lost

when power is removed. A backup supply at VBACKUP will be sufficient to keep them.

8.1 NMEA output sentences

NMEA output sentences

Type

content

Common GPS sentences

$GPRMC

Recommended Minimum Navigation Information

$GPGGA

Fix Data, Time, Position and fix related data for a GPS receiver

$GPGSA

DOP and active satellites

$GPGLL

Geographic Position - Latitude/Longitude

$GPGSV

GPS Satellites in view

8.2 NMEA command interface

GNS302uLP NMEA command interface allows to control settings and the extended functions. The

command interface specification is available in an extra document:

NMEA_Interface_manual_MTK_Vx manual.

Two groups of commands are available:

Setting commands do modify the behavior of the module.

Note : modified settings will be valid as long as the module is powered through VBACKUP. (f.e. :

setting of a new baud rate). After removing VBACKUP, all settings are reset to their default values.

Action commands will perform the specified action one time after the command has been received.

(f.e. : request for cold start)

Commands are always started with $PTMK, directly followed by the command number 000..999.

Each command must be terminated by *<chksum>and a <CR><LF>.

The checksum calculation is simple, just XOR all the bytes between the $ and the * (not including

the delimiters themselves). Then use the hexadecimal ASCII format.

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

9 PHYSICAL DIMENSIONS

TOP VIEW

all units in mm, tolerance is ±0.2mm

0.90

0.55

2.00

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

10 RECOMMENDED PAD LAYOUT

all units in mm

Footprint Top View

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

11 DESIGN GUIDELINES

Although GNS302uLP GPS receiver provides best performance at low power consumption, special

care should be taken to provide clean signal and clean power supplies. Power lines should be

blocked near to the receiver with low ESR capacitors.

Radiated noise from neighbour components may also reduce the performance of the receiver.

11.1 PCB LAYOUT GUIDELINES

GNS302uLP uses a high performance chip antenna design.

For optimum performance, a ground plane area is needed on the main board. This area should be

at least 20 x 30mm, a larger ground like 30 x 60mm is recommended.

The groundplane can be part of the main ground layer of the mainboard, some (small) components

in the neighbourhood of the antenna are acceptable. Do not place any bulky or metallic components

near to the antenna (in a distance below 30mm) to avoid unwanted electromagnetic shielding

effects.

It’s recommended to place GNS302uLP at the rim of the main PCB, so that the antenna has a wide

unobstructed working angle.

Position of chip

antenna on

302uLP module

Groundplane on

top & bottom.

Clearence area.

Keep clear on all

layers !

Be sure to solder

these pads

reliably !

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

The marked clearance area below the antenna must be kept clear in any case ! Do not design any

copper tracks or planes in the clearance area !

The two ground solder pads near the chip antenna must be reliably soldered to mainboard

groundplanes to make the antenna work at high performance.

Please do not place any shielding or lids in the area 5mm below your PCB under the Clearance area.

Plastic enclosures can also have impact on the antenna. Avoid that the antenna is in touch with any

enclosure parts. Product testing should be performed with the PCB already mounted in the final

enclosure.

Generally the rules for good and low noise design should be followed:

 Use a solid ground plane, best on layer 2 of the mainboard

 Keep noisy components (µC, switch mode supplies) as far as possible away from sensitive

antenna inputs

 Place decoupling capacitors near to the source of noise and provide a short and low

induction connection to ground (use multi-vias if needed)

 EMC filters or noise filtering coils or beads can help to reduce the noise level further.

 Select system clocks in a way, that no harmonics will match the GPS frequency of 1575.42

MHz

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

12 NMEA DATA interface

GNS302uLP provides NMEA (National Marine Electronics Association) 0183 compatible data.

A set of proprietary NMEA commands is available to send control messages to the receiver.

These commands are described in a separate document: NMEA_Interface_manual_MTK_Vx.

For standard operation, no commands are needed; the module will start outputting NMEA sentences

after power supply has been attached. GNS302uLP will always start communication output with

9600 bit per second.

If non standard options are needed (f.e. other baud rate , other NMEA sequence) they can be

programmed from host controller during runtime.

Important note : Options set by using NMEA command interface are not persistent! They will be

lost when power is removed. A backup supply at VBACKUP will be sufficient to keep them.

12.1 NMEA output sentences

NMEA output sentences

Type

content

Common GPS sentences

$GPRMC

Recommended Minimum Navigation Information

$GPGGA

Fix Data, Time, Position and fix related data for a GPS receiver

$GPGSA

DOP and active satellites

$GPGLL

Geographic Position - Latitude/Longitude

$GPGSV

GPS Satellites in view

Refer to NMEA_Interface_manual_MTK_Vx document for more information.

12.2 NMEA command interface

GNS302uLP NMEA command interface allows to control settings and the extended functions. The

command interface specification is available in an extra document:

NMEA_Interface_manual_MTK_Vx.

Two groups of commands are available:

Setting commands do modify the behavior of the module.

Note : Modified settings will be valid as long as the module is powered through VBACKUP. (f.e. :

setting of a new baud rate). After removing VBACKUP, all settings are reset to their default values.

Action commands will perform the specified action one time after the command has been received.

(f.e. : request for cold start)

Commands are always started with $PTMK, directly followed by the command number 000..999.

Each command must be terminated by *<chksum>and a <CR><LF>.

The checksum calculation is simple, just XOR all the bytes between the $ and the * (not including

the delimiters themselves). Then use the hexadecimal ASCII format.

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

13 MATERIAL INFORMATION

Complies to ROHS standard

ROHS documentations are available on request

Contact surface: gold over nickel

14 RECOMMENDED SOLDERING REFLOW PROFILE

Notes:

1. GNS302uLP should be soldered in upright soldering position. In case of head-over soldering, please prevent

shielding / GNS302uLP receiver from falling down.

2. Do never exceed maximum peak temperature

3. Reflow cycles allowed : 1 time

4. RohS compliance status will be lost if soldered with solder containing lead (Pb).

5. This device is not applicable for flow solder processing

6. This device is not applicable for solder iron process

100

200

300

t[sec]

100

200

T[°C]

250°C max

250°C for 10 sec max

230°C for 40 sec max

160°C  190°C 120 sec

reflow solder

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

15 PACKAGE INFORMATION

15.1 TAPE

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

15.2 REEL

Number of devices: 1500 pcs/reel

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

16 ORDERING INFORMATION

Ordering information

Type

Part#

label marking

Description

GNS302uLP

4037735105393

GNS302uLP

YYWW

2.5_39

GNS302uLP GPS receiver

YYWW  date code

FW Version

SN  serial number

17 ENVIRONMENTAL INFORMATION

This product is free of environmental hazardous substances and complies with 2002/95/EC. (RoHS

directive).

GPS receiver GNS302uLP

Datasheet

preliminary specification

V 0.2, Jan 26 2016

18 MOISTURE SENSITIVITY

This device must be prebaked before being put to reflow solder process.

Disregarding may cause destructive effects like chip cracking, which leaves the device defective !

Shelf life

6 months , sealed

Possible prebake recommendations

12 hrs @ 60°C

Floor life (time from prebake to solder process)

<72 hrs

19 DOCUMENT REVISION HISTORY

V0.1

Sep 23 2015

P.Skaliks

initial document, preliminary

V0.2

Jan 26 2016

P.Skaliks

Laser marking def

20 RELATED DOCUMENTS

Title

Description / file

Available from

NMEA_Interface_manual_MTK_Vx

Detailed description of NMEA

commands and protocol

www.forum.gns-gmbh.com

www.gns-gmbh.com

 GNS GMBH 2015

THE INFORMATION IN THIS DOCUMENTATION DOES NOT FORM ANY QUOTATION OR CONTRACT. TECHNICAL DATA ARE DUE TO BE CHANGED WITHOUT

NOTICE.

NO LIABILITY WILL BE ACCEPTED BY THE PUBLISHER FOR ANY CONSEQUENCE OF THIS DOCUMENT'S USE.

REPRODUCTION IN WHOLE OR IN PART IS PROHIBITED WITHOUT THE PRIOR WRITTEN CONSENT OF THE COPYRIGHT OWNER