Warning:Some customers may want Linx radio frequency (“RF”)
!
products to control machinery or devices remotely, including machinery
or devices that can cause death, bodily injuries, and/or property
damage if improperly or inadvertently triggered, particularly in industrial
settings or other applications implicating life-safety concerns (“Life and
Property Safety Situations”).
Table of Contents
1 Description
1 Features
1 Applications Include
NO OEM LINX REMOTE CONTROL OR FUNCTION MODULE
SHOULD EVER BE USED IN LIFE AND PROPERTY SAFETY
SITUATIONS. No OEM Linx Remote Control or Function Module
should be modified for Life and Property Safety Situations. Such
modification cannot provide sufficient safety and will void the product’s
regulatory certification and warranty.
Customers may use our (non-Function) Modules, Antenna and
Connectors as part of other systems in Life Safety Situations, but
only with necessary and industry appropriate redundancies and
in compliance with applicable safety standards, including without
limitation, ANSI and NFPA standards. It is solely the responsibility
of any Linx customer who uses one or more of these products to
incorporate appropriate redundancies and safety standards for the Life
and Property Safety Situation application.
Do not use this or any Linx product to trigger an action directly
from the data line or RSSI lines without a protocol or encoder/
decoder to validate the data. Without validation, any signal from
another unrelated transmitter in the environment received by the module
could inadvertently trigger the action.
All RF products are susceptible to RF interference that can prevent
communication. RF products without frequency agility or hopping
implemented are more subject to interference. This module does not
have a frequency hopping protocol built in.
Do not use any Linx product over the limits in this data guide.
Excessive voltage or extended operation at the maximum voltage could
cause product failure. Exceeding the reflow temperature profile could
cause product failure which is not immediately evident.
Do not make any physical or electrical modifications to any Linx
product. This will void the warranty and regulatory and UL certifications
and may cause product failure which is not immediately evident.
2 Ordering Information
2 Absolute Maximum Ratings
2 ElectricalSpecications
4 Pin Assignments
4 Pin Descriptions
5 A Brief Overview of GPS
6 Time To First Fix (TTFF)
6 Module Description
7 Backup Battery
7 Power Supply Requirements
8 The 1PPS Output
8 Power Control
9 Antenna Considerations
10 Slow Start Time
11 Interfacing with NMEA Messages
12 NMEA Output Messages
19 Input Messages
31 Typical Applications
32 Master Development System
33 Microstrip Details
34 Board Layout Guidelines
35 Pad Layout
36 Production Guidelines
36 Hand Assembly
36 Automated Assembly
38 Appendix A
Page 3
46 Resources
47 Notes
RM Series GPS Receiver
Data Guide
Description
The RM Series GPS receiver module is a
self-contained high-performance Global
Positioning System receiver. Based on
the MediaTek MT3337E chipset, it can
simultaneously acquire on 66 channels and
track on up to 22 channels. This gives the
module fast lock times and high position
accuracy even at low signal levels.
The module’s exceptional sensitivity gives it
superior performance, even in dense foliage and urban canyons. Its very
low power consumption helps maximize runtimes in battery powered
applications. The module outputs standard NMEA data messages through
a UART interface.
Housed in a compact reflow-compatible SMD package, the receiver
requires no programming or additional RF components (except an antenna)
to form a complete GPS solution. This makes the RM Series easy to
integrate, even by engineers without previous RF or GPS experience.
components. Always wear an ESD wrist strap and observe proper ESD
handling procedures when working with this device. Failure to observe
this precaution may result in module damage or failure.
Features
• MediaTek chipset
• High sensitivity (–161dBm)
• Fast TTFF at low signal levels
• ±11ns 1PPS accuracy
• Battery-backed SRAM
• No programming necessary
Applications Include
• Positioning and Navigation
• Location and Tracking
• Security/Loss-Prevention
• No external RF components
needed (except an antenna)
• No production tuning
• UART serial interface
• Power control features
• Compact SMD package
• Surveying
• Logistics
• Fleet Management
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1
Revised 10/6/2016
Page 4
Ordering Information
Ordering Information
Part NumberDescription
RXM-GPS-RM-xRM Series GPS Receiver Module
MDEV-GPS-RMRM Series GPS Receiver Master Development System
EVM-GPS-RMRM Series Evaluation Module
x = “T” for Tape and Reel, “B” for Bulk
Reels are 1,000 pieces. Quantities less than 1,000 pieces are supplied in bulk
Figure 2: Ordering Information
Absolute Maximum Ratings
Absolute Maximum Ratings
Supply Voltage V
CC
+4.3VDC
Input Battery Backup Voltage+4.3VDC
VCC_RF Output Current50mA
Operating Temperature−40 to +85ºC
Storage Temperature−40 to +85ºC
Exceeding any of the limits of this section may lead to permanent damage to the device.
Furthermore, extended operation at these maximum ratings may reduce the life of this
device.
Figure 3: Absolute Maximum Ratings
ElectricalSpecications
RM Series GPS Receiver Specifications
ParameterSymbolMin.Typ.Max.Units Notes
Power Supply
Operating Voltage V
Supply Currentl
CC
CC
Peak44mA1
Acquisition14mA1
Tracking12mA1
Standby0.135mA1
Backup Battery VoltageV
Backup Battery CurrentI
BAT
BAT
3.03.34.3VDC
2.04.3VDC
6µA2
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23
RM Series GPS Receiver Specifications
ParameterSymbolMin.Typ.Max.Units Notes
VOUT Output VoltageV
VOUT Output CurrentI
Output Low VoltageV
Output High VoltageV
Output Low CurrentI
Output High CurrentI
Input Low VoltageV
Input High VoltageV
Input Low CurrentI
Input High CurrentI
Minimum RESET PulseT
OUT
OUT
OL
OH
OL
OH
IL
IH
IL
IH
RST
2.72.82.9VDC
30mA1
0.4VDC
2.4V
CC
2.0mA
2.0mA
–0.30.8VDC
2.03.6VDC
–11µA3
–11µA3
1ms
Antenna Port
RF ImpedanceR
IN
50Ω
Receiver Section
Receiver Sensitivity
Tracking–161dBm
Cold Start–143dBm
Acquisition Time
Hot Start (Open Sky)1s
Hot Start (Indoor)30s
Cold Start32s
Cold Start, AGPS15s
Position Accuracy
Autonomous3m
1PPS Accuracy-1111ns4
Altitude50,000m
Velocity515m/s
ChipsetMediaTek MT3337E
FrequencyL1 1575.42MHz, C/A code
Channels22 tracking, 66 acquisition
Update Rate1Hz default, up to 10Hz
Protocol SupportNMEA 0183 ver 3.01
1. VCC = 3.3V, without active antenna, position fix is available
2. VCC = 0V
3. No pull-up or pull-down on the lines
4. Relative to other RM Series modules, not to UTC time
Figure 4: Electrical Specifications
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Page 5
Pin Assignments
A Brief Overview of GPS
The Global Positioning System (GPS) is a U.S.-owned utility that freely and
NC1
NC2
1PPS3
TX4
RX5
GND21
NC6
LCKIND7
RESET8
NC9
NC10
GND20
RFIN19
GND18
VOUT17
NC16
GND22
NC15
NC14
NC13
VCC12
VBACKUP11
continuously provides positioning, navigation, and timing (PNT) information.
Originally created by the U.S. Department of Defense for military
applications, the system was made available without charge to civilians
in the early 1980s. The global positioning system consists of a nominal
constellation of 24 satellites orbiting the earth at about 12,000 nautical
miles in height. The pattern and spacing of the satellites allow at least four
to be visible above the horizon from any point on the Earth. Each satellite
transmits low power radio signals which contain three different bits of
information; a pseudorandom code identifying the satellite, ephemeris data
which contains the current date and time as well as the satellite’s health,
and the almanac data which tells where each satellite should be at any time
throughout the day.
Figure 5: RM Series GPS Receiver Pinout (Top View)
Pin Descriptions
Pin Descriptions
Pin NumberNameI/O Description
1, 2, 6, 9, 10,
13, 14, 15, 16
31PPSO1 Pulse Per Second
4TXOSerial output (default NMEA)
5RXISerial input (default NMEA)
7LCKINDO
8RESETI
11VBACKUPP
12VCCPSupply Voltage
17VOUTO2.8V output for an active antenna
18, 20, 21, 22GNDPGround
19RFINIGPS RF signal input
NC−No electrical connection
Lock Indicator. Outputs a 100ms pulse every
second when a GPS fix is available.
Active low module reset. This line is pulled high
internally. Leave it unconnected if it is not used.
Backup battery supply voltage. This line must be
powered to enable the module.
A GPS receiver receives and times the signals sent by multiple satellites
and calculates the distance to each satellite. If the position of each satellite
is known, the receiver can use triangulation to determine its position
anywhere on the earth. The receiver uses four satellites to solve for four
unknowns; latitude, longitude, altitude and time. If any of these factors is
already known to the system, an accurate position (fix) can be obtained
with fewer satellites in view. Tracking more satellites improves calculation
accuracy. In essence, the GPS system provides a unique address for every
square meter on the planet.
A faster Time To First Fix (TTFF) is also possible if the satellite information
is already stored in the receiver. If the receiver knows some of this
information, then it can accurately predict its position before acquiring an
updated position fix. For example, aircraft or marine navigation equipment
may have other means of determining altitude, so the GPS receiver would
only have to lock on to three satellites and calculate three equations to
provide the first position fix after power-up.
Figure 6: RM Series GPS Receiver Pin Descriptions
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Time To First Fix (TTFF)
TTFF is often broken down into three parts.
Cold: A cold start is when the receiver has no accurate knowledge of its
position or time. This happens when the receiver’s internal Real Time Clock
(RTC) has not been running or it has no valid ephemeris or almanac data.
In a cold start, the receiver takes up to 30 seconds to acquire its position.
Warm: A typical warm start is when the receiver has valid almanac and time
data and has not significantly moved since its last valid position calculation.
This happens when the receiver has been shut down for more than 2
hours, but still has its last position, time, and almanac saved in memory,
and its RTC has been running. The receiver can predict the location of the
current visible satellites and its location; however, it needs to wait for an
ephemeris broadcast (every 30 seconds) before it can accurately calculate
its position.
Hot: A hot start is when the receiver has valid ephemeris, time, and
almanac data. In a hot start, the receiver takes 1 second to acquire its
position. The time to calculate a fix in this state is sometimes referred to as
Time to Subsequent Fix or TTSF.
Module Description
The RM Series GPS Receiver module is based on the MediaTek MT3337E
chipset, which consumes less power than competitive products while
providing exceptional performance even in dense foliage and urban
canyons. No external RF components are needed other than an antenna.
The simple serial interface and industry standard NMEA protocol make
integration of the RM Series into an end product extremely straightforward.
The module’s high-performance RF architecture allows it to receive GPS
signals that are as low as –161dBm. The RM Series can track up to 22
satellites at the same time. Once locked onto the visible satellites, the
receiver calculates the range to the satellites and determines its position
and the precise time. It then outputs the data through a standard serial port
using several standard NMEA protocol formats.
Backup Battery
The module is designed to work with a backup battery that keeps the
SRAM memory and the RTC powered when the RF section and the main
GPS core are powered down. This enables the module to have a faster
Time To First Fix (TTFF) when it is powered back on. The memory and
clock pull about 6µA. This means that a small lithium battery is sufficient to
power these sections. This significantly reduces the power consumption
and extends the main battery life while allowing for fast position fixes when
the module is powered back on.
The backup battery must be installed for the module to be enabled.
Power Supply Requirements
The module requires a clean, well-regulated power source. While it is
preferable to power the unit from a battery, it can operate from a power
supply as long as noise is less than 20mV. Power supply noise can
significantly affect the receiver’s sensitivity, therefore providing clean power
to the module should be a high priority during design.
Bypass capacitors should be placed as close as possible to the module.
The values should be adjusted depending on the amount and type of noise
present on the supply line.
1
NC
2
NC
3
1PPS
4
TX
5
RX
21
GND
6
NC
7
LCKIND
8
RESET
9
NC
10
NC
Figure 7: Supply Filter
VBACKUP
GND
RFIN
GND
VOUT
NC
GND
NC
NC
NC
VCC
20
19
18
17
16
22
15
14
13
VCC
12
11
GND
The GPS core handles all of the necessary initialization, tracking, and
calculations autonomously, so no programming is required. The RF section
is optimized for low level signals, and requires no production tuning.
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The 1PPS Output
The 1PPS line outputs 1 pulse per second on the rising edge of the GPS
second when the receiver has an over-solved navigation solution from five
or more satellites. The pulse has a duration of 100ms by default with the
rising edge on the GPS second. This line is low until the receiver acquires a
3D fix. The pulse width can be adjusted with a serial command.
The GPS second is based on the atomic clocks in the satellites, which are
monitored and set to Universal Time master clocks. This output and the
time calculated from the satellite transmissions can be used as a clock
feature in an end product. It has a ±11ns accuracy relative to other RM
Series GPS receiver modules.
Power Control
The RM Series GPS Receiver module offers several ways to control the
module’s power. A serial command puts the module into a low-power
standby mode that consumes only 135µA of current. An external processor
can be used to power the module on and off to conserve battery power.
Standby mode is configured by command 161.
Note: The receiver duty cycle mode was removed from modules with
date code 1612 and later.
Antenna Considerations
The RM Series module is designed to utilize a wide variety of external
antennas. The module has a regulated power output which simplifies
the use of GPS antenna styles which require external power. This allows
the designer great flexibility, but care must be taken in antenna selection
to ensure optimum performance. For example, a handheld device may
be used in many varying orientations so an antenna element with a wide
and uniform pattern may yield better overall performance than an antenna
element with high gain and a correspondingly narrower beam. Conversely,
an antenna mounted in a fixed and predictable manner may benefit from
pattern and gain characteristics suited to that application. Evaluating
multiple antenna solutions in real-world situations is a good way to rapidly
assess which will best meet the needs of your application.
For GPS, the antenna should have good right hand circular polarization
characteristics (RHCP) to match the polarization of the GPS signals.
Ceramic patches are the most commonly used style of antenna, but
there are many different shapes, sizes and styles of antennas available.
Regardless of the construction, they will generally be either passive or
active types. Passive antennas are simply an antenna tuned to the correct
frequency. Active antennas add a Low Noise Amplifier (LNA) after the
antenna and before the module to amplify the weak GPS satellite signals.
For active antennas, a 300 ohm ferrite bead can be used to connect the
VOUT line to the RFIN line. This bead prevents the RF from getting into the
power supply, but allows the DC voltage onto the RF trace to feed into the
antenna. A series capacitor inside the module prevents this DC voltage
from affecting the bias on the module’s internal LNA.
Maintaining a 50 ohm path between the module and antenna is critical.
Errors in layout can significantly impact the module’s performance. Please
review the layout guidelines section carefully to become more familiar with
these considerations.
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Page 8
Slow Start Time
The most critical factors in start time are current ephemeris data, signal
strength and sky view. The ephemeris data describes the path of each
satellite as they orbit the earth. This is used to calculate the position of
a satellite at a particular time. This data is only usable for a short period
of time, so if it has been more than a few hours since the last fix or if the
location has significantly changed (a few hundred miles), then the receiver
may need to wait for a new ephemeris transmission before a position can
be calculated. The GPS satellites transmit the ephemeris data every 30
seconds. Transmissions with a low signal strength may not be received
correctly or be corrupted by ambient noise. The view of the sky is important
because the more satellites the receiver can see, the faster the fix and the
more accurate the position will be when the fix is obtained.
If the receiver is in a very poor location, such as inside a building, urban
canyon, or dense foliage, then the time to first fix can be slowed. In very
poor locations with poor signal strength and a limited view of the sky with
outdated ephemeris data, this could be on the order of several minutes.
In the worst cases, the receiver may need to receive almanac data, which
describes the health and course data for every satellite in the constellation.
This data is transmitted every 15 minutes. If a lock is taking a long time, try
to find a location with a better view of the sky and fewer obstructions. Once
locked, it is easier for the receiver to maintain the position fix.
Interfacing with NMEA Messages
Linx modules default to the NMEA protocol. Output messages are sent
from the receiver on the TX line and input messages are sent to the receiver
on the RX line. By default, output messages are sent once every second.
Details of each message are described in the following sections.
The NMEA message format is as follows: <Message-ID + Data Payload +
Checksum + End Sequence>. The serial data structure defaults to
9,600bps, 8 data bits, 1 start bit, 1 stop bit, and no parity. Each message
starts with a $ character and ends with a <CR> <LF>. All fields within
each message are separated by a comma. The checksum follows the *
character and is the last two characters, not including the <CR> <LF>.
It consists of two hex digits representing the exclusive OR (XOR) of all
characters between, but not including, the $ and * characters. When
reading NMEA output messages, if a field has no value assigned to it, the
comma will still be placed following the previous comma. For example,
{,04,,,,,2.0,} shows four empty fields between values 04 and 2.0. When
writing NMEA input messages, all fields are required, none are optional. An
empty field will invalidate the message and it will be ignored.
Reading NMEA output messages:
• Initialize a serial interface to match the serial data structure of the GPS
receiver.
• Read the NMEA data from the TX pin into a receive buffer.
• Separate it into six buffers, one for each message type. Use the
characters ($) and <CR> <LF> as end points for each message.
• For each message, calculate the checksum as mentioned above to
compare with the received checksum.
• Parse the data from each message using commas as field separators.
• Update the application with the parsed field values.
• Clear the receive buffer and be ready for the next set of messages.
Writing NMEA input messages:
• Initialize a serial interface to match the serial data structure of the GPS
receiver.
• Assemble the message to be sent with the calculated checksum.
• Transmit the message to the receiver on the RX line.
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Page 9
NMEA Output Messages
The following sections outline the data structures of the various NMEA
messages that are supported by the module. By default, the NMEA
commands are output at 9,600bps, 8 data bits, 1 start bit, 1 stop bit, and
no parity.
Six messages are output at a 1Hz rate by default. The ZDA message is
supported, but disabled by default. These messages are shown in Figure 8.
NMEA Output Messages
NameDescription
GGAContains the essential fix data which provide location and accuracy
GLLContains just position and time
GSAContains data on the Dilution of Precision (DOP) and which satellites are used
GSV
RMCContains the minimum data of time, position, speed and course
Figure 8: NMEA Output Messages
Details of each message and examples are given in the following sections.
Contains the satellite location relative to the receiver and its signal to noise
ratio. Each message can describe 4 satellites so multiple messages may be
output depending on the number of satellites being tracked.
VTGContains the course and speed over the ground
ZDAContains the date and time
GGA – Global Positioning System Fix Data
Figure 9 contains the values for the following example:
Figure 16 contains the values for the following example:
$GPVTG,79.65,T,,M,2.69,N,5.0,K,A*38
Recommended Minimum Specific GPS Data Example
NameExampleUnitsDescription
Message ID$GPRMCRMC protocol header
UTC Time053740.000hhmmss.sss
Status AA=data valid or V=data not valid
Latitude2503.6319ddmm.mmmm
N/S IndicatorNN=north or S=south
Longitude12136.0099dddmm.mmmm
E/W IndicatorEE=east or W=west
Speed over ground2.69knotsTRUE
Course over ground79.65degrees
Date100106ddmmyy
Magnetic Variationdegrees Not available, null field
Variation SenseE=east or W=west (not shown)
ModeA
Checksum*53
<CR> <LF>End of message termination
Figure 15: Recommended Minimum Specific GPS Data Example
A=autonomous, E=DR, N= Data not
valid, R=Coarse Position, S=Simulator
Course Over Ground and Ground Speed Example
NameExampleUnitsDescription
Message ID$GPVTGVTG protocol header
Course over ground79.65degrees Measured heading
ReferenceTTRUE
Course over grounddegrees Measured heading (N/A, null field)
ReferenceMMagnetic
Speed over ground2.69knotsMeasured speed
UnitsNKnots
Speed over ground5.0km/hrMeasured speed
UnitsKKilometer per hour
ModeA
Checksum*38
<CR> <LF>End of message termination
Figure 16: Course Over Ground and Ground Speed Example
A=autonomous, N= Data not valid,
R=Coarse Position, S=Simulator
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Page 12
ZDA – Universal Time and Date
Figure 17 contains the values for the following example:
$GPZDA,183746.000,22,08,2014,,*56
Universal Time and Date Example
NameExampleUnitsDescription
Message ID$GPZDAZDA protocol header
UTC Time183746.000hhmmss.sss
Day2201 to 31
Month0801 to 12
Year20141980 to 2079
Local Zone HourOffset from UTC; set to null
Local Zone MinutesOffset from UTC; set to null
Checksum*56
<CR> <LF>End of message termination
Figure 17: Universal Time and Date Example
Start-up Response
The module outputs a message when it starts up to indicate its state. The
normal start-up message is shown below and the message formatting is
shown in Figure 18.
$PMTK010,001*2E<CR><LF>
Start-up Response Example
NameExampleDescription
Message ID$PMTK010 Message header
Message
MSG
ChecksumCKSUM
End Sequence <CR> <LF> End of message termination
Figure 18: Start-up Response Example
System Message
0 = Unknown
1 = Start-up
2 = Notification for the host supporting EPO
3 = Transition to Normal operation is successful
Input Messages
The following outlines the serial commands input into the module for
configuration. There are 3 types of input messages: commands, writes and
reads. The module outputs a response for each input message.
The commands are used to change the operating state of the module.
The writes are used to change the module’s configuration and the reads
are used to read out the current configuration. Messages are formatted as
shown in Figure 19. All fields in each message are separated by a comma.
Serial Data Structure
NameExampleDescription
Start Sequence$PMTK
Message ID<MID>
PayloadDATAMessage specific data.
ChecksumCKSUM
End Sequence<CR> <LF>
Figure 19: Serial Data Structure
Figure 20 shows the input commands.
Input Commands
NameDescription
101Hot Re-start
102Warm Re-start
103Cold Re-start
104Restore Default Configuration
161Standby Mode
220Position Fix Interval
251Serial Port Baud Rate
255Sync 1PPS and NMEA Messages
2851PPS Configuration
286Enable Active Interference Cancellation
Message Identifier consisting of three numeric
characters.
CKSUM is a two-hex character checksum as
defined in the NMEA specification, NMEA-0183
Standard for Interfacing Marine Electronic Devices.
Checksums are required on all input messages.
Each message must be terminated using Carriage
Return (CR) Line Feed (LF) (\r\n, 0x0D0A) to cause
the receiver to process the input message. They
are not printable ASCII characters, so are omitted
from the examples.
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1819
Figure 20: Input Commands
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Page 13
The write and read messages are shown in Figure 21. A write message
triggers an acknowledgement from the module. A read message triggers a
response message containing the requested information.
Input Write and Read Messages
DescriptionWrite ID Read ID Response ID
Set NMEA Output Messages314414514
Set Datum330430530
Static Navigation Threshold386447527
Enable Ephemeris Prediction869869869
101 – Hot Re-start
This command instructs the module to conduct a hot re-start using all of
the data stored in memory. Periodic mode and static navigation settings are
returned to default when this command is executed.
$PMTK101*32<CR><LF>
102 – Warm Re-start
This command instructs the module to conduct a warm re-start that does
not use the saved ephemeris data. Periodic mode and static navigation
settings are returned to default when this command is executed.
Figure 21: Input Write and Read Messages
The module responds to commands with response messages. The
acknowledge message is formatted as shown in Figure 22.
Acknowledge Message
NameExampleDescription
Start Sequence$PMTK
Message ID001Acknowledge Identifier
CommandCMDThe command that triggered the acknowledge
CKSUM is a two-hex character checksum as
defined in the NMEA specification, NMEA-0183
Standard for Interfacing Marine Electronic Devices.
Checksums are required on all input messages.
Each message must be terminated using Carriage
Return (CR) Line Feed (LF) (\r\n, 0x0D0A) to cause
the receiver to process the input message. They
are not printable ASCII characters, so are omitted
from the examples.
$PMTK102*31<CR><LF>
103 – Cold Re-start
This command instructs the module to conduct a cold re-start that does
not use any of the data from memory. Periodic mode and static navigation
settings are returned to default when this command is executed.
$PMTK103*30<CR><LF>
104 – Restore Default Configuration
This command instructs the module to conduct a cold re-start and return
all configurations to the factory default settings.
$PMTK104*37<CR><LF>
161 – Standby Mode
This command instructs the module to enter a low power standby mode.
Any activity on the RX line wakes the module. Only enter standby mode
after the module acquires a position fix.
$PMTK161,0*28<CR><LF>
Figure 22: Acknowledge Message
The module outputs the startup message when it wakes up.
$PMTK010,001*2E<CR><LF>
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Page 14
220 – Position Fix Interval
This command sets the position fix interval. This is the time between when
the module calculates its position.
Position Fix Interval Command and Response
Command
StartMsg IDIntervalChecksumEnd
$PMTK220,Ival*Cksum<CR><LF>
Response
StartMsg IDCMDFlagChecksumEnd
$PMTK001,220,Flg*Cksum<CR><LF>
Figure 23: Position Fix Interval Command and Response
Ival = the interval time in milliseconds.
The interval must be larger than 100ms. Faster rates require that the baud
rate be increased, the number of messages that are output be decreased
or both. The module automatically calculates the required data bandwidth
and returns an action failed response (Flg = 2) if the interval is faster than
the module can output all of the required messages at the current baud
rate. The following example sets the interval to 1 second.
251 – Serial Port Baud Rate
This command sets the serial port baud rate.
Serial Port Baud Rate Command and Response
Command
StartMsg IDRateChecksumEnd
$PMTK251,Rate*Cksum<CR><LF>
Response
StartMsg IDCMDFlagChecksumEnd
$PMTK001,251,Flg*Cksum<CR><LF>
Figure 24: Serial Port Baud Rate Command and Response
Rate = serial port baud rate
0 = default setting (9,600bps)
4800
9600
14400
19200
38400
57600
115200
$PMTK220,1000*1F<CR><LF>
It is recommended to use interval rates of 100ms, 200ms, 500ms,
1,000ms and 2,000ms. Although permissible, non-standard intervals are
not guaranteed or recommended.
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2223
The following example sets the baud rate to 57,600bps.
$PMTK251,57600*2C<CR><LF>
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Page 15
255 – Sync 1PPS and NMEA Messages
UTC 12:00:00UTC 12:00:01
This command enables or disables synchronization between the 1PPS
pulse and the NMEA messages. When enabled, the beginning of the
NMEA message on the UART is fixed to between 170 and 180ms after the
rising edge of the 1PPS pulse. The NMEA message describes the position
and time as of the rising edge of the 1PPS pulse.
Sync 1PPS and NMEA Messages Command and Response
Command
StartMsg IDEnableChecksumEnd
$PMTK255,Enable*Cksum<CR><LF>
Response
StartMsg IDCMDFlagChecksumEnd
$PMTK001,255,Flg*Cksum<CR><LF>
285 – 1PPS Configuration
This command configures the 1PPS output.
1PPS Configuration Command and Response
Command
StartMsg IDTypePulse WidthChecksumEnd
$PMTK285,Type,Width*Cksum<CR><LF>
Response
StartMsg IDCMDFlagChecksumEnd
$PMTK001,285,Flg*Cksum<CR><LF>
Figure 27: 1PPS Configuration Messages Command and Response
Figure 28 shows the Type values.
Figure 25: Sync 1PPS and NMEA Messages Command and Response
1PPS
TX
UTC 12:00:00UTC 12:00:01
170ms ~ 180ms
Figure 26: 1PPS and NMEA Message Synchronization
This is only supported at a 1Hz NMEA message rate. It is disabled by
default.
The following examples show the use of this command.
The Width field is the width of the 1PPS pulse in milliseconds. The max
width is 900ms at a 1Hz NMEA message rate. The default is 100ms.
These configurations are maintained during hot and warm starts, but are
lost on cold starts and restore to factory defaults.
Set the 1PPS to activate after a 3D fix and have a 10ms pulse width.
$PMTK285,2,10*0E<CR><LF>
Set the 1PPS to activate after a 3D fix and have a 900ms pulse width.
– –
2425
$PMTK285,2,900*36<CR><LF>
– –
Page 16
286 – Enable Active Interference Cancellation
This command enables or disables active interference cancellation. This
feature helps remove jamming and narrow-band interference to enable a
position fix.
Enable Active Interference Cancellation Command and Response
Command
StartMsg IDEnableChecksumEnd
$PMTK286,Enable*Cksum<CR><LF>
Response
StartMsg IDCMDFlagChecksumEnd
$PMTK001,286,Flg*Cksum<CR><LF>
Figure 29: Enable Active Interference Cancellation Messages Command and Response
By default, this is enabled after the first fix is acquired.
The following examples show the use of this command.
Figure 30: NMEA Output Messages Command and Response
GLL RMC VTG GGA GSA GSVDATAZDA 0 CKEnd
ID
Msg
CMD Flag CKEnd
ID
Msg
CKEnd
ID
Msg
GLL RMC VTG GGA GSA GSVDATAZDA 0 CKEnd
ID
Each field has a value of 1 through 5 which indicates how many position
fixes should be between each time the message is output. A 1 configures
the message to be output every position fix. A value of 2 configures the
message to be output every other position fix and a value of 5 configures
it to be output every 5th position fix. This along with message 220 sets the
time between message outputs.
A value of 0 disables the message.
The example below sets all of the messages to be output every fix.
The following example reads the current message configuration and the
module responds that all supported messages are configured to be output
on every position fix.
Reference datums are data sets that describe the shape of the Earth
based on a reference point. There are many regional datums based on a
convenient local reference point. Different datums use different reference
points, so a map used with the receiver output must be based on the same
datum. WGS84 is the default world referencing datum.
Static Navigation Threshold
This configures the speed threshold to trigger static navigation. If the
measured speed is below the threshold then the module holds the current
position and sets the speed to zero.
Static Navigation Threshold Command and Response
Write Message
StartMsg IDTholdChecksumEnd
$PMTK386,Thold*Cksum<CR><LF>
Acknowledge Response Message
StartMsg IDCMDFlagChecksumEnd
$PMTK001,386,Flg*Cksum<CR><LF>
Read Message
StartMsg IDChecksumEnd
$PMTK447*35<CR><LF>
Response Message
StartMsg IDTholdChecksumEnd
$PMTK527,Thold*Cksum<CR><LF>
Figure 32: Static Navigation Threshold Command and Response
Static navigation is disabled by default, and is set for walking speed.
Thold = speed threshold, from 0 to 2.0m/s. 0 = disabled.
The following example sets the threshold to 1.2m/s.
The module supports 223 different datums. These are listed in Appendix A.
The following example sets the datum to WGS84.
$PMTK330,0*2E<CR><LF>
The following example reads the current datum and the module replies with
datum 0, which is WGS84.
$PMTK430*35<CR><LF>
$PMTK530,0*28<CR><LF>
– –
2829
$PMTK386,1.2*3E<CR><LF>
The following example reads the static navigation threshold and the module
responds with 1.2m/s
$PMTK447*35<CR><LF>
$PMTK527,1.20*03<CR><LF>
The static navigation threshold configuration returns to the default values
after a reset or restart.
– –
Page 18
EASYTM Ephemeris Prediction
VCC
EASY™ is a function to generate orbit predictions for faster cold and warm
starts. It does this without the need for Internet connectivity or assistance
from the host processor. The predictions are good for up to 3 days and are
automatically updated when the module obtains a good position fix.
EASYTM Ephemeris Prediction Command and Response
Write Message
StartMsg IDTypeEnableChecksumEnd
$PMTK869,Type,Enable*Cksum<CR><LF>
Figure 33: Ephemeris Prediction Command and Response
Figure 34 shows the Type values.
Typical Applications
Figure 35 shows the RM Series GPS receiver in a typical application using
a passive antenna.
µP
GND
GND
VCC
RX
TX
GND
1
2
3
4
5
21
6
7
8
9
10
NC
NC
1PPS
TX
RX
GND
NC
LCKIND
RESET
NC
NC
VBACKUP
GND
RFIN
GND
VOUT
NC
GND
NC
NC
NC
VCC
20
19
18
17
16
22
15
14
13
12
11
GND
VCC
GND
Ephemeris Prediction Type Values
ValueDescription
0Query the current state of prediction (enabled or disabled)
1Set the state of prediction
2Result of a query
Figure 34: Ephemeris Prediction Type Values
The Enable field is 0 to disable or 1 to enable. It is not used in a query.
The response to a set command is a standard acknowledgement packet.
EASYTM is enabled by default. This is only supported with a 1Hz NMEA
Figure 35: Circuit Using the RM Series Module with a Passive Antenna
A microcontroller UART is connected to the receiver’s UART for passing
data and commands. A 3.3V coin cell battery is connected to the
VBACKUP line to provide power to the module’s memory when main
power is turned off.
Figure 36 shows the module using an active antenna.
Figure 36: Circuit Using the RM Series Module with a an Active Antenna
A 300Ω ferrite bead is used to put power from VOUT onto the antenna line
to power the active antenna.
– –
Page 19
Master Development System
The RM Series Master Development System provides all of the tools
necessary to evaluate the RM Series GPS receiver module. The system
includes a fully assembled development board, an active antenna,
development software and full documentation.
Figure 37: The RM Series Master Development System
The development board includes a power supply, a prototyping area for
custom circuit development, and an OLED display that shows the GPS
data without the need for a computer. A USB interface is also included
for use with a PC running custom software or the included development
software.
Microstrip Details
A transmission line is a medium whereby RF energy is transferred from
one place to another with minimal loss. This is a critical factor, especially in
high-frequency products like Linx RF modules, because the trace leading
to the module’s antenna can effectively contribute to the length of the
antenna, changing its resonant bandwidth. In order to minimize loss and
detuning, some form of transmission line between the antenna and the
module should be used unless the antenna can be placed very close (<1⁄8in)
to the module. One common form of transmission line is a coax cable and
another is the microstrip. This term refers to a PCB trace running over a
ground plane that is designed to serve as a transmission line between the
module and the antenna. The width is based on the desired characteristic
impedance of the line, the thickness of the PCB and the dielectric constant
of the board material. For standard 0.062in thick FR-4 board material, the
trace width would be 111 mils. The correct trace width can be calculated
for other widths and materials using the information in Figure 39 and
examples are provided in Figure 40. Software for calculating microstrip lines
is also available on the Linx website.
Trace
Board
Ground plane
Figure 38: The Master Development System Software
The Master Development System software enables configuration of the
receiver and displays the satellite data output by the receiver. The software
can select from among all of the supported NMEA protocols for display of
the data.
Full documentation for the board and software is included in the
development system, making integration of the module straightforward.
– –
3233
Figure 39: Microstrip Formulas
Example Microstrip Calculations
Dielectric Constant
4.801.83.5950.0
4.002.03.0751.0
2.553.02.1248.0
Figure 40: Example Microstrip Calculations
Width/Height
Ratio (W/d)
Effective Dielectric
Constant
– –
Characteristic
Impedance (Ω)
Page 20
Board Layout Guidelines
The module’s design makes integration straightforward; however, it
is still critical to exercise care in PCB layout. Failure to observe good
layout techniques can result in a significant degradation of the module’s
performance. A primary layout goal is to maintain a characteristic
50-ohm impedance throughout the path from the antenna to the module.
Grounding, filtering, decoupling, routing and PCB stack-up are also
important considerations for any RF design. The following section provides
some basic design guidelines which may be helpful.
During prototyping, the module should be soldered to a properly laid-out
circuit board. The use of prototyping or “perf” boards will result in poor
performance and is strongly discouraged.
The module should, as much as reasonably possible, be isolated from
other components on your PCB, especially high-frequency circuitry such as
crystal oscillators, switching power supplies, and high-speed bus lines.
Each of the module’s ground pins should have short traces tying
immediately to the ground plane through a via.
Bypass caps should be low ESR ceramic types and located directly
adjacent to the pin they are serving.
A 50-ohm coax should be used for connection to an external antenna.
A 50-ohm transmission line, such as a microstrip, stripline or coplanar
waveguide should be used for routing RF on the PCB. The Microstrip
Details section provides additional information.
In some instances, a designer may wish to encapsulate or “pot” the
product. There is a wide variety of potting compounds with varying
dielectric properties. Since such compounds can considerably impact
RF performance and the ability to rework or service the product, it is
the responsibility of the designer to evaluate and qualify the impact and
suitability of such materials.
When possible, separate RF and digital circuits into different PCB regions.
Make sure internal wiring is routed away from the module and antenna, and
is secured to prevent displacement.
Do not route PCB traces directly under the module. There should not be
any copper or traces under the module on the same layer as the module,
just bare PCB. The underside of the module has traces and vias that could
short or couple to traces on the product’s circuit board.
The Pad Layout section shows a typical PCB footprint for the module. A
ground plane (as large and uninterrupted as possible) should be placed on
a lower layer of your PC board opposite the module. This plane is essential
for creating a low impedance return for ground and consistent stripline
performance.
Use care in routing the RF trace between the module and the antenna
or connector. Keep the trace as short as possible. Do not pass under
the module or any other component. Do not route the antenna trace on
multiple PCB layers as vias will add inductance. Vias are acceptable for
tying together ground layers and component grounds and should be used
in multiples.
Pad Layout
The pad layout diagram in Figure 41 is designed to facilitate both hand and
automated assembly.
0.036
(0.92)
0.020
(0.50)
0.028
(0.70)
0.512
(13.00)
0.036
0.050
(1.27)
Figure 41: Recommended PCB Layout
(0.92)
0.050
(1.27)
0.045
(1.15)
– –
3435
– –
Page 21
Production Guidelines
The module is housed in a hybrid SMD package that supports hand and
automated assembly techniques. Since the modules contain discrete
components internally, the assembly procedures are critical to ensuring
the reliable function of the modules. The following procedures should be
reviewed with and practiced by all assembly personnel.
Hand Assembly
Pads located on the bottom
of the module are the primary
mounting surface (Figure 42).
Since these pads are inaccessible
during mounting, castellations
that run up the side of the module
have been provided to facilitate
solder wicking to the module’s
underside. This allows for very
quick hand soldering for prototyping and small volume production. If the
recommended pad guidelines have been followed, the pads will protrude
slightly past the edge of the module. Use a fine soldering tip to heat the
board pad and the castellation, then introduce solder to the pad at the
module’s edge. The solder will wick underneath the module, providing
reliable attachment. Tack one module corner first and then work around the
device, taking care not to exceed the times in Figure 43.
Soldering Iron
Tip
Solder
PCB Pads
Figure 42: Soldering Technique
Castellations
Reflow Temperature Profile
The single most critical stage in the automated assembly process is the
reflow stage. The reflow profile in Figure 44 should not be exceeded
because excessive temperatures or transport times during reflow will
irreparably damage the modules. Assembly personnel need to pay careful
attention to the oven’s profile to ensure that it meets the requirements
necessary to successfully reflow all components while still remaining
within the limits mandated by the modules. The figure below shows the
recommended reflow oven profile for the modules.
Peak: 240+0/-5°C
220°C
Preheat:
150 - 200°C
120 - 150sec
2 - 4°C/sec
30°C
Figure 44: Maximum Reflow Temperature Profile
2 - 3°C/sec
25 - 35sec
60 - 80sec
Warning: Pay attention to the absolute maximum solder times.
Absolute Maximum Solder Times
Hand Solder Temperature: +427ºC for 10 seconds for lead-free alloys
Reflow Oven: +240°C max (see Figure 44)
Figure 43: Absolute Maximum Solder Times
Automated Assembly
For high-volume assembly, the modules are generally auto-placed.
The modules have been designed to maintain compatibility with reflow
processing techniques; however, due to their hybrid nature, certain aspects
of the assembly process are far more critical than for other component
types. Following are brief discussions of the three primary areas where
caution must be observed.
– –
3637
Shock During Reflow Transport
Since some internal module components may reflow along with the
components placed on the board being assembled, it is imperative that
the modules not be subjected to shock or vibration during the time solder
is liquid. Should a shock be applied, some internal components could be
lifted from their pads, causing the module to not function properly.
Washability
The modules are wash-resistant, but are not hermetically sealed. Linx
recommends wash-free manufacturing; however, the modules can be
subjected to a wash cycle provided that a drying time is allowed prior
to applying electrical power to the modules. The drying time should be
sufficient to allow any moisture that may have migrated into the module
to evaporate, thus eliminating the potential for shorting damage during
power-up or testing. If the wash contains contaminants, the performance
may be adversely affected, even after drying.
– –
Page 22
Appendix A
The following datums are supported by the RM Series.
RM Series GPS Receiver Supported Datums
Number DatumRegion
0WGS1984International
1TokyoJapan
2Tokyo
3User SettingUser Setting
4AdindanBurkina Faso
5AdindanCameroon
6AdindanEthiopia
7AdindanMali
8AdindanMean for Ethiopia, Sudan
9AdindanSenegal
10AdindanSudan
11AfgooyeSomalia
12Ain El Abd1970Bahrain
13Ain El Abd1970Saudi Arabia
14American Samoa1962American Samoa Islands
15Anna 1 Astro1965Cocos Island
16Antigua Island Astro1943Antigua(Leeward Islands)
17Arc1950Botswana
18Arc1950Burundi
19Arc1950Lesotho
20Arc1950Malawi
21Arc1950
22Arc1950Swaziland
23Arc1950Zaire
24Arc1950Zambia
25Arc1950Zimbabwe
26Arc1960Mean For Kenya Tanzania
27Arc1960Kenya
28Arc1960Tanzania
29Ascension Island1958Ascension Island
30Astro Beacon E 1945Iwo Jima
Mean for Japan, South Korea,
Okinawa
Mean for Botswana, Lesotho, Malawi,
Swaziland, Zaire, Zambia, Zimbabwe
RM Series GPS Receiver Supported Datums
Number DatumRegion
31Astro Dos 71/4St Helena Island
32Astro Tern Island (FRIG) 1961Tern Island
33Astronomical Station 1952Marcus Island
34Australian Geodetic 1966Australia, Tasmania
35Australian Geodetic 1984Australia, Tasmania
36Ayabelle LighthouseDjibouti
37Bellevue (IGN)Efate and Erromango Islands
38Bermuda 1957Bermuda
39BissauGuuinea-Bissau
40Bogota ObservatoryColombia
41Bukit RimpahIndonesia (Bangka and Belitung Ids)
42Camp Area AstroAntarctica (McMurdi Camp Area)
43Campo InchauspeArgentina
44Canton Astro1966Phoenix Island
45CapeSouth Africa
46Cape CanaveralBahamas, Florida
47CarthageTunisia
48Chatham Island Astro1971New Zealand (Chatham Island)
114Montserrat Island Astro 1958Montserrat (Leeward Island)
115NahrwanOman (Masirah Island)
116NahrwanSaudi Arabia
117NahrwanUnited Arab Emirates
118Naparima BWITrinidad and Tobago
119North American 1927Alaska (Excluding Aleutian Ids)
120North American 1927
121North American 1927
122North American 1927
123North American 1927Bahamas (San Salvador Islands)
124North American 1927Canada (Alberta, British Columbia)
125North American 1927Canada (Manitoba, Ontario)
Alaska (Aleutian Ids East of 180
degW)
Alaska (Aleutian Ids West of 180
degW)
Bahamas (Except San Salvador
Islands)
– –
4041
– –
Page 24
RM Series GPS Receiver Supported Datums
Number DatumRegion
126North American 1927
127North American 1927
128North American 1927Canada (Yukon)
129North American 1927Canal Zone
130North American 1927Cuba
131North American 1927Greenland (Hayes Peninsula)
132North American 1927
133North American 1927
134North American 1927Mean for Canada
135North American 1927Mean for Conus
136North American 1927
137North American 1927
138North American 1927Mexico
139North American 1983Alaska (Excluding Aleutian Ids)
140North American 1983Aleutian Ids
141North American 1983Canada
142North American 1983Conus
143North American 1983Hawaii
144North American 1983Mexico, Central America
145North Sahara 1959Algeria
146Observatorio Meteorologico 1939Azores (Corvo and Flores Islands)
147Old Egyptian 1907Egypt
148Old HawaiianHawaii
149Old HawaiianKauai
150Old HawaiianMaui
151Old HawaiianMean for Hawaii, Kauai, Maui, Oahu
152Old HawaiianOahu
153OmanOman
Canada (New Brunswick,
Newfoundland, Nova Scotia, Quebec)
Canada (Northwest Territories,
Saskatchewan)
Mean For Antigua, Barbados,
Barbuda, Caicos Islands, Cuba,
Dominican, Grand Cayman, Jamaica,
Turks Islands
Mean for Belize, Costa Rica, El
Salvador, Guatemala, Honduras,
Nicaragua
Mean for Conus (East of Mississippi,
River Including Louisiana, Missouri,
Minnesota)
Mean for Conus (West of Mississippi,
River Excluding Louisiana, Minnesota,
Missouri)
RM Series GPS Receiver Supported Datums
Number DatumRegion
154Ordnance Survey Great Britain 1936 England
155Ordnance Survey Great Britain 1936 England, Isle of Man, Wales
156Ordnance Survey Great Britain 1936
157Ordnance Survey Great Britain 1936 Scotland, Shetland Islands
158Ordnance Survey Great Britain 1936 Wales
159Pico de las NievesCanary Islands
160Pitcairn Astro 1967Pitcairn Island
161Point 58Mean for Burkina Faso and Niger
162Pointe Noire 1948Congo
163Porto Santo 1936Porto Santo, Madeira Islands
164Provisional South American 1956Bolivia
165Provisional South American 1956Chile (Northern Near 19 deg S)
166Provisional South American 1956Chile (Southern Near 43 deg S)
167Provisional South American 1956Colombia
168Provisional South American 1956Ecuador
169Provisional South American 1956Guyana
170Provisional South American 1956
171Provisional South American 1956Peru
172Provisional South American 1956Venezuela
173Provisional South Chilean 1963Chile (Near 53 deg S) (Hito XVIII)
174Puerto RicoPuerto Rico, Virgin Islands
175Pulkovo 1942Russia
176Qatar NationalQatar
177QornoqGreenland (South)
178ReunionMascarene Island
179Rome 1940Italy (Sardinia)
180S-42 (Pulkovo 1942)Hungary
181S-42 (Pulkovo 1942)Poland
182S-42 (Pulkovo 1942)Czechoslavakia
183S-42 (Pulkovo 1942)Lativa
184S-42 (Pulkovo 1942)Kazakhstan
185S-42 (Pulkovo 1942)Albania
186S-42 (Pulkovo 1942)Romania
187S-JTSKCzechoslavakia (Prior 1 Jan1993)
Mean For England, Isle of Man,
Scotland, Shetland Island, Wales
Mean for Bolivia Chile, Colombia,
Ecuador, Guyana, Peru, Venezuela
– –
4243
– –
Page 25
RM Series GPS Receiver Supported Datums
Number DatumRegion
188Santo (Dos) 1965Espirito Santo Island
189Sao BrazAzores (Sao Miguel, Santa Maria Ids)
190Sapper Hill 1943East Falkland Island
191SchwarzeckNamibia
192Selvagem Grande 1938Salvage Islands
193Sierra Leone 1960Sierra Leone
194South American 1969Argentina
195South American 1969Bolivia
196South American 1969Brazil
197South American 1969Chile
198South American 1969Colombia
199South American 1969Ecuador
200South American 1969Ecuador (Baltra, Galapagos)
201South American 1969Guyana
Mean For Argentina, Bolivia, Brazil,
202South American 1969
203South American 1969Paraguay
204South American 1969Peru
205South American 1969Trinidad and Tobago
206South American 1969Venezuela
207South AsiaSingapore
208Tananarive Observatory 1925Madagascar
209Timbalai 1948Brunei, E Malaysia (Sabah Sarawak)
210TokyoJapan
211Tokyo
212TokyoOkinawa
213TokyoSouth Korea
214Tristan Astro 1968Tristam Da Cunha
215Viti Levu 1916Fiji (Viti Levu Island)
216Voirol 1960Algeria
217Wake Island Astro 1952Wake Atoll
218Wake-Eniwetok 1960Marshall Islands
219WGS 1972Global Definition
Chile, Colombia, Ecuador, Guyana,
Paraguay, Peru, Trinidad and Tobago,
Venezuela
Mean for Japan, South Korea,
Okinawa
RM Series GPS Receiver Supported Datums
Number DatumRegion
220WGS 1984Global Definition
221YacareUruguay
222ZanderijSuriname
Figure 45: Supported Datums
– –
4445
– –
Page 26
Resources
Support
For technical support, product documentation, application notes, regulatory
guidelines and software updates, visit www.linxtechnologies.com
RF Design Services
For customers who need help implementing Linx modules, Linx offers
design services including board layout assistance, programming,
certification advice and packaging design. For more complex RF solutions,
Apex Wireless, a division of Linx Technologies, creates optimized designs
with RF components and firmware selected for the customer’s application.
Call +1 800 736 6677 (+1 541 471 6256 if outside the United States) for
more information.
Antenna Factor Antennas
Linx’s Antenna Factor division has the
industry’s broadest selection of antennas
for a wide variety of applications. For
customers with specialized needs,
custom antennas and design services are
available along with simulations of antenna
performance to speed development. Learn more at www.linxtechnologies.
com.
by
Notes
– –
4647
– –
Page 27
Linx Technologies
159 Ort Lane
Merlin, OR, US 97532
Phone: +1 541 471 6256
Fax: +1 541 471 6251
www.linxtechnologies.com
Disclaimer
Linx Technologies is continually striving to improve the quality and function of its products. For this reason, we
reserve the right to make changes to our products without notice. The information contained in this Data Guide
is believed to be accurate as of the time of publication. Specifications are based on representative lot samples.
Values may vary from lot-to-lot and are not guaranteed. “Typical” parameters can and do vary over lots and
application. Linx Technologies makes no guarantee, warranty, or representation regarding the suitability of any
product for use in any specific application. It is the customer’s responsibility to verify the suitability of the part for
the intended application. NO LINX PRODUCT IS INTENDED FOR USE IN ANY APPLICATION WHERE THE SAFETY
OF LIFE OR PROPERTY IS AT RISK.
Linx Technologies DISCLAIMS ALL WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE. IN NO EVENT SHALL LINX TECHNOLOGIES BE LIABLE FOR ANY OF CUSTOMER’S INCIDENTAL OR
CONSEQUENTIAL DAMAGES ARISING IN ANY WAY FROM ANY DEFECTIVE OR NON-CONFORMING PRODUCTS
OR FOR ANY OTHER BREACH OF CONTRACT BY LINX TECHNOLOGIES. The limitations on Linx Technologies’
liability are applicable to any and all claims or theories of recovery asserted by Customer, including, without
limitation, breach of contract, breach of warranty, strict liability, or negligence. Customer assumes all liability
(including, without limitation, liability for injury to person or property, economic loss, or business interruption) for
all claims, including claims from third parties, arising from the use of the Products. The Customer will indemnify,
defend, protect, and hold harmless Linx Technologies and its officers, employees, subsidiaries, affiliates,
distributors, and representatives from and against all claims, damages, actions, suits, proceedings, demands,
assessments, adjustments, costs, and expenses incurred by Linx Technologies as a result of or arising from any
Products sold by Linx Technologies to Customer. Under no conditions will Linx Technologies be responsible for
losses arising from the use or failure of the device in any application, other than the repair, replacement, or refund
limited to the original product purchase price. Devices described in this publication may contain proprietary,
patented, or copyrighted techniques, components, or materials. Under no circumstances shall any user be
conveyed any license or right to the use or ownership of such items.