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NEO/LEA-M8T Datasheet

U-Blox America Inc.

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Datasheet

NEO/LEA-M8T
u-blox M8 concurrent GNSS timing modules
Data Sheet
Highlights:
Concurrent reception of GPS/QZSS, GLONASS, BeiDou, Galileo
Market leading acquisition and tracking sensitivity
Optimized accuracy and availability with Survey-in and single-
satellite timing
Minimized power consumption with low duty-cycle operation
Maximized reliability with Integrity monitoring and alarms
Backward compatible with LEA-5T, LEA-6T and NEO-6T
www.u-blox.com
UBX-15025193 - R03
NEO/LEA-M8T - Data Sheet
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Document Information
Title
NEO/LEA-M8T
Subtitle
u-blox M8 concurrent GNSS timing modules
Document type
Data Sheet
Document number
UBX-15025193
Revision and Date
21-Jun-2016
Document status
Production Information
Document status explanation
Objective Specification
Document contains target values. Revised and supplementary data will be published later.
Advance Information
Document contains data based on early testing. Revised and supplementary data will be published later.
Early Production Information
Document contains data from product verification. Revised and supplementary data may be published later.
Production Information
Document contains the final product specification.
This document applies to the following products:
Product name
Type number
ROM/FLASH version
PCN reference
LEA-M8T
LEA-M8T-0-10
Flash FW 3.01 TIM 1.10
UBX-16004907
NEO-M8T
NEO-M8T-0-10
Flash FW 3.01 TIM 1.10
UBX-16005636
u-blox reserves all rights to this document and the information contained herein. Products, names, logos and designs described herein
may in whole or in part be subject to intellectual property rights. Reproduction, use, modification or disclosure to third parties of this
document or any part thereof without the express permission of u-blox is strictly prohibited.
The information contained herein is provided “as is” and u-blox assumes no liability for the use of the information. No warranty, either
express or implied, is given, including but not limited, with respect to the accuracy, correctness, reliability and fitness for a particular
purpose of the information. This document may be revised by u-blox at any time. For most recent documents, visit www.u-blox.com.
Copyright © 2016, u-blox AG.
u-blox® is a registered trademark of u-blox Holding AG in the EU and other countries. ARM® is the registered trademark of ARM Limited in
the EU and other countries.
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Contents
Contents .............................................................................................................................. 3
1 Functional description .................................................................................................. 6
1.1 Overview .............................................................................................................................................. 6
1.2 Product features ................................................................................................................................... 6
1.3 Performance ......................................................................................................................................... 7
1.4 Block diagram ....................................................................................................................................... 8
1.5 Supported GNSS Constellations ............................................................................................................ 8
1.5.1 GPS ............................................................................................................................................... 9
1.5.2 GLONASS ...................................................................................................................................... 9
1.5.3 BeiDou .......................................................................................................................................... 9
1.5.4 Galileo ........................................................................................................................................... 9
1.6 Assisted GNSS (A-GNSS) ....................................................................................................................... 9
1.6.1 AssistNowTM Online ...................................................................................................................... 10
1.6.2 AssistNowTM Offline ..................................................................................................................... 10
1.6.3 AssistNowTM Autonomous ............................................................................................................ 10
1.7 Augmentation systems ....................................................................................................................... 10
1.7.1 Satellite-Based Augmentation System (SBAS) ............................................................................... 10
1.7.2 QZSS ........................................................................................................................................... 10
1.7.3 IMES ............................................................................................................................................ 11
1.7.4 Differential GPS (D-GPS) .............................................................................................................. 11
1.8 Precision timing, raw data and low duty-cycle operation ..................................................................... 11
1.8.1 Time mode .................................................................................................................................. 11
1.8.2 Timepulse and frequency outputs ................................................................................................ 12
1.8.3 Time mark ................................................................................................................................... 12
1.8.4 Timing integrity and availability ................................................................................................... 12
1.8.5 Raw Data .................................................................................................................................... 13
1.8.6 Low duty cycle operation ............................................................................................................. 13
1.9 TIMEPULSE ......................................................................................................................................... 13
1.10 Odometer ....................................................................................................................................... 14
1.11 Data logging ................................................................................................................................... 14
1.12 Geofencing ..................................................................................................................................... 14
1.13 Message Integrity Protection ........................................................................................................... 14
1.14 Spoofing Detection ......................................................................................................................... 14
1.15 EXTINT: External interrupt ............................................................................................................... 14
1.15.1 Power control .............................................................................................................................. 14
1.15.2 Aiding ......................................................................................................................................... 15
1.16 Protocols and interfaces .................................................................................................................. 15
1.17 Interfaces ........................................................................................................................................ 15
1.17.1 UART ........................................................................................................................................... 15
1.17.2 USB ............................................................................................................................................. 15
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1.17.3 SPI ............................................................................................................................................... 15
1.17.4 Display Data Channel (DDC) ........................................................................................................ 16
1.18 Clock generation ............................................................................................................................ 16
1.18.1 Oscillators .................................................................................................................................... 16
1.18.2 Real-Time Clock (RTC) and Hardware Backup mode .................................................................... 16
1.19 Power management ........................................................................................................................ 16
1.19.1 Operating modes ........................................................................................................................ 16
1.20 Antenna .......................................................................................................................................... 17
1.20.1 Antenna type .............................................................................................................................. 17
1.20.2 Antenna supervision .................................................................................................................... 17
2 Pin definition .............................................................................................................. 18
2.1 NEO-M8T pin assignment ................................................................................................................... 18
2.2 LEA-M8T pin assignment .................................................................................................................... 19
3 Configuration management ...................................................................................... 20
3.1 Interface selection (D_SEL) .................................................................................................................. 20
4 Electrical specification ................................................................................................ 21
4.1 Absolute maximum rating .................................................................................................................. 21
4.2 Operating conditions .......................................................................................................................... 22
4.3 Indicative current requirements ........................................................................................................... 22
4.4 SPI timing diagrams ............................................................................................................................ 23
4.4.1 Timing recommendations ............................................................................................................ 24
4.5 DDC timing diagrams ......................................................................................................................... 24
5 Mechanical specifications .......................................................................................... 25
5.1 NEO-M8T ........................................................................................................................................... 25
5.2 LEA-M8T ............................................................................................................................................ 26
6 Reliability tests and approvals .................................................................................. 27
6.1 Reliability tests .................................................................................................................................... 27
6.2 Approvals ........................................................................................................................................... 27
7 Product handling & soldering .................................................................................... 28
7.1 Packaging ........................................................................................................................................... 28
7.1.1 Reels ........................................................................................................................................... 28
7.1.2 NEO-M8T Tapes .......................................................................................................................... 28
7.1.3 LEA-M8T Tapes ........................................................................................................................... 29
7.2 Shipment, storage and handling ......................................................................................................... 29
7.2.1 Moisture sensitivity levels ............................................................................................................. 29
7.2.2 Reflow soldering ......................................................................................................................... 29
7.2.3 ESD handling precautions ............................................................................................................ 30
8 Default messages ....................................................................................................... 31
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9 Labeling and ordering information ........................................................................... 32
9.1 NEO-M8T product labeling ................................................................................................................. 32
9.2 LEA-M8T product labeling .................................................................................................................. 32
9.3 Explanation of codes........................................................................................................................... 32
9.4 Ordering codes ................................................................................................................................... 33
Related documents........................................................................................................... 34
Revision history ................................................................................................................ 34
Contact .............................................................................................................................. 35
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1 Functional description
1.1 Overview
The NEO-M8T and LEA-M8T concurrent GNSS modules deliver high integrity, precision timing in demanding
applications world-wide. Support for BeiDou, GLONASS and Galileo constellations in addition to GPS enables
compliance with national requirements. Enhanced sensitivity and concurrent constellation reception extend
coverage and integrity to challenging signal environments. Survey-in and fixed-position navigation reduce timing
jitter, even at low signal levels, and enable synchronization to be maintained with as few as one single satellite in
view. Support for on/off low duty cycle operation reduces power consumption for battery-powered applications.
u-blox timing products include timing integrity measures with Receiver Autonomous Integrity Monitoring (RAIM)
and continuous phase uncertainty estimation. They feature high dynamic range radios with both analog and
digital interference mitigation, supporting applications in wireless communications equipment.
Sophisticated RF-architecture and interference suppression ensure maximum performance even in GNSS-hostile
environments. The LEA-M8T includes a SAW filter and antenna power supervision and is perfect for use with
active antennas or antenna signal distribution systems. The NEO-M8T includes an additional LNA, improving
performance when connected directly to a passive antenna, with support for external antenna supply
management if required. Both modules include Flash memory for field upgrade. UART, SPI and DDC (I2C
compatible) interfaces provide connectivity and enable synergies with most u-blox cellular modules.
The M8T timing modules are delivered in u-blox’s established LEA and NEO form-factors with standard pin-out,
allowing ready migration from previous product generations.
u-blox timing products can make use of u-blox AssistNow or industry standard aiding data. This reduces the time
to first fix and delivers exceptional acquisition sensitivity, even on first installation before precise location, time or
frequency are known.
u-blox M8 modules use GNSS chips qualified according to AEC-Q100, are manufactured in ISO/TS 16949
certified sites, and fully tested on a system level. Qualification tests are performed as stipulated in the ISO16750
standard: “Road vehicles Environmental conditions and testing for electrical and electronic equipment”.
1.2 Product features
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1.3 Performance
Parameter
Specification
Receiver type
72-channel u-blox M8 engine
GPS L1C/A, SBAS L1C/A, QZSS L1C/A, QZSS L1 SAIF, GLONASS L1OF, BeiDou B1, Galileo E1B/C
GNSS
GPS &
GLONASS
GPS &
BeiDou
GPS
GLONASS
BeiDou
Galileo
Time-To-First-Fix1
Cold start
25 s
28 s
29 s
30 s
34 s
45 s
Aided start
2 s
2 s
2 s
2 s
3 s
7 s
Hot start
1 s
1 s
1 s
1 s
1 s
1 s
Sensitivity2
Tracking &
Navigation
-167 dBm
-166 dBm
-166 dBm
-166 dBm
-159 dBm
-159 dBm
Aided
acquisition3
-157 dBm
-157 dBm
-157 dBm
-151 dBm
-146 dBm
-142 dBm
Reacquisition
-160 dBm
-160 dBm
-160 dBm
-156 dBm
-156 dBm
-153 dBm
Cold start
-148 dBm
-148 dBm
-148 dBm
-145 dBm
-143 dBm
-138 dBm
Hot start
-160 dBm
-160 dBm
-160 dBm
-156 dBm
-155 dBm
-151 dBm
Horizontal
position
accuracy4
Autonomous
2.5 m
2.5 m
2.5 m
4.0 m
3.0 m
TBC5
SBAS
2.0 m
2.0 m
2.0 m
N/A
N/A
N/A
Velocity
accuracy6
0.05 m/s
0.05 m/s
0.05 m/s
0.1 m/s
0.1 m/s
0.1 m/s
Heading
accuracy6
0.3 degrees
0.3 degrees
0.3 degrees
0.4 degrees
0.5 degrees
0.5 degrees
Max navigation
update rate7
4 Hz
4 Hz
10 Hz
10 Hz
10 Hz
10 Hz
Time pulse
frequency
0.25 Hz…10 MHz
Time pulse
accuracy8
Clear sky
20 ns
Indoor
500 ns
Operational
limits9
Dynamics
4 g
Altitude
50,000 m
Velocity
500 m/s
Table 1: NEO/LEA-M8T performance in different GNSS modes (default: concurrent reception of GPS and GLONASS)
1
All satellites at -130 dBm
2
Demonstrated with a good external LNA
3
Time: 1s, Position: 1km, Almanac, Ephemeris
4
CEP, 50%, 24 hours static, -130 dBm, > 6 SVs
5
To be confirmed when Galileo reaches full operational capability
6
50% @ 30 m/s
7
Rates with SBAS disabled for > 98% fix report rate under typical conditions
8
1-sigma
9
Assuming Airborne < 4 g platform
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1.4 Block diagram
Figure 1: NEO-M8T block diagram
Figure 2: LEA-M8T block diagram
1.5 Supported GNSS Constellations
The NEO-M8T and LEA-M8T GNSS modules are concurrent GNSS receivers that can receive and track multiple
GNSS systems: GPS, Galileo, GLONASS and BeiDou. Owing to the dual-frequency RF front-end architecture,
either GLONASS or BeiDou can be processed concurrently with GPS and Galileo signals providing reception of
three GNSS systems. By default M8T receivers are configured for concurrent GPS and GLONASS, including QZSS
reception. If power consumption is a key factor, then the receiver should be configured for a single GNSS
operation using GPS, Galileo, GLONASS or BeiDou with QZSS and SBAS disabled. The modules can be
configured to receive any single GNSS constellation or within the set of permissible combinations shown below.
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GPS
Galileo
GLONASS
BeiDou
Table 2 Permissible GNSS combinations (= enabled)
The augmentation systems: SBAS and QZSS can be enabled only if GPS operation is configured.
Galileo is not enabled in the default configuration.
1.5.1 GPS
The NEO-M8T and LEA-M8T GNSS modules are designed to receive and track the L1C/A signals provided at
1575.42 MHz by the Global Positioning System (GPS). The modules can receive and process GPS concurrently
with Galileo and one of GLONASS or BeiDou.
1.5.2 GLONASS
The NEO-M8T and LEA-M8T GNSS modules can receive and process GLONASS concurrently with GPS and
Galileo together or BeiDou. The Russian GLONASS satellite system is a fully deployed alternative to the US-based
Global Positioning System (GPS). The modules are designed to receive and track the L1OF signals GLONASS
provides around 1602 MHz. The ability to receive and track GLONASS L1OF satellite signals allows design of
GLONASS receivers where required by regulations.
1.5.3 BeiDou
The NEO-M8T and LEA-M8T GNSS modules can receive and process BeiDou concurrently with GPS and Galileo
together or GLONASS. The modules are designed to receive and track the B1 signals provided at 1561.098 MHz
by the BeiDou Navigation Satellite System. The ability to receive and track BeiDou B1 satellite signals in
conjunction with GPS results in higher coverage, improved reliability and better accuracy. Global coverage is
scheduled for 2020.
1.5.4 Galileo
The NEO-M8T and LEA-M8T GNSS modules can receive and track the E1-B/C signals centered on the GPS L1
frequency band. GPS and Galileo signals can be processed concurrently together with either BeiDou or GLONASS
signals, enhancing coverage, reliability and accuracy. The SAR return link message (RLM) parameters for both
short and long versions are decoded by the receiver and made available to users via UBX proprietary messages.
See the u-blox 8 / u-blox M8 Receiver Description Including Protocol Specification [3] for more information.
For further guidance on the use of specific GNSS constellations in timing applications please contact your
local u-blox support team.
1.6 Assisted GNSS (A-GNSS)
Supply of aiding information, such as ephemeris, almanac, approximate position and time, will reduce the time
to first fix significantly and improve the acquisition sensitivity. The NEO-M8T and LEA-M8T products support the
u-blox AssistNow Online and AssistNow Offline A-GNSS services, support AssistNow Autonomous, and are OMA
SUPL compliant.
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1.6.1 AssistNowTM Online
With AssistNow Online, an internet-connected GNSS device downloads assistance data from u-blox’s AssistNow
Online Service at system start-up. AssistNow Online is network-operator independent and globally available.
Devices can be configured to request only ephemeris data for those satellites currently visible at their location,
thus minimizing the amount of data transferred.
The AssistNow Online service provides data for GPS, GLONASS, BeiDou, Galileo and QZSS.
1.6.2 AssistNowTM Offline
With AssistNow Offline, users download u-blox’s long-term orbit data from the Internet at their convenience.
The orbit data can be stored in the NEO-M8T and LEA-M8T GNSS receivers' SQI flash memory. Thus the service
requires no connectivity at system start-up, enabling a position fix within seconds, even when no network is
available. AssistNow Offline offers augmentation for up to 35 days.
AssistNow Offline service provides data for GPS and GLONASS only, BeiDou and Galileo are not currently
supported.
1.6.3 AssistNowTM Autonomous
AssistNow Autonomous provides aiding information without the need for a host or external network
connection. Based on previous broadcast satellite ephemeris data downloaded to and stored by the GNSS
receiver, AssistNow Autonomous automatically generates accurate satellite orbital data (“AssistNow
Autonomous data”) that is usable for future GNSS position fixes. The concept capitalizes on the periodic nature
of GNSS satellites: their position in the sky is basically repeated every 24 hours. By capturing strategic ephemeris
data at specific times over several days, the receiver can predict accurate satellite ephemeris for up to six days
after initial reception.
u-blox’s AssistNow Autonomous benefits are:
Faster fix in situations where GNSS satellite signals are weak
No connectivity required
Compatible with AssistNow Online and Offline (can work stand-alone, or in tandem with these services)
No integration effort; calculations are done in the background, transparent to the user.
For more details see the u-blox 8 / u-blox M8 Receiver Description Including Protocol Specification [3] and
MGA Services User Guide [6].
1.7 Augmentation systems
1.7.1 Satellite-Based Augmentation System (SBAS)
The NEO-M8T and LEA-M8T timing receivers optionally support SBAS (including WAAS in the US, EGNOS in
Europe, MSAS in Japan and GAGAN in India) to deliver improved location accuracy within the regions covered.
However, the additional inter-standard time calibration step used during SBAS reception results in degraded time
accuracy overall.
SBAS reception is disabled by default in NEO-M8T and LEA-M8T.
1.7.2 QZSS
The Quasi-Zenith Satellite System (QZSS) is a regional navigation satellite system that transmits additional GPS L1
C/A signals for the Pacific region covering Japan and Australia. The NEO-M8T and LEA-M8T modules are able to
receive and track these signals concurrently with GPS signals, resulting in better availability especially under
challenging signal conditions, e.g. in urban canyons. The L1- SAIF signal provided by QZSS can be enabled for
reception via a GNSS configuration message.
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1.7.3 IMES
The Japanese Indoor MEssaging System (IMES) system is used for indoor position reporting using low-power
transmitters which broadcast a GPSlike signal. The NEO-M8T and LEA-M8T modules can be configured to
receive and demodulate the signal to provide an in-door location estimate.
This service is authorized and available only in Japan.
IMES reception is disabled by default
1.7.4 Differential GPS (D-GPS)
The use of Differential-GPS data improves GPS position accuracy using real time data from a nearby reference
receiver or network. D-GPS starts on receipt of valid data according RTCM 10402.3: “RECOMMENDED
STANDARDS FOR DIFFERENTIAL GNSS”. RTCM cannot be used together with SBAS and is applicable only to GPS
signals in the NEO-M8T and LEA-M8T. The RTCM implementation supports the following RTCM 2.3 messages:
Message Type
Description
1
Differential GPS Corrections
2
Delta Differential GPS Corrections
3
GPS Reference Station Parameters
9
GPS Partial Correction Set
Table 3: Supported RTCM 2.3 messages
For more details see the u-blox 8 / u-blox M8 Receiver Description Including Protocol Specification [3].
1.8 Precision timing, raw data and low duty-cycle operation
1.8.1 Time mode
The NEO-M8T and LEA-M8T support:
a special fixed-position mode improving timing stability in stationary applications
optional single-SV time tracking for difficult RF environments (available in fixed-position mode only)
Receiver Autonomous Integrity Monitoring (RAIM) indication for timing
dual configurable 0.25 Hz to 10 MHz time-pulse outputs
Improved timing performance can be delivered by using the fixed-position mode in stationary applications. In this
mode, positioning uncertainties are eliminated from the calculation of time which reduces the error and variation
in the phase of the TIMEPULSE signal outputs. The known position also reduces the minimum number of
measurements and hence good satellite signals required to enable Receiver Autonomous Integrity Monitoring
(RAIM), reported in message UBX-TIM-TP.
Operation with as few as one single satellite signal is supported in this mode, enabling continuity of timing in
situations with extremely limited sky view. The minimum number of signals required may be increased using
message UBX-CFG-NAVX5.
Fixed-position mode is configured with the message CFG-TMODE2 according to Table 4 below either by
initiating a survey-in process (which can take some time to complete accurately) or by entering the position of
the antenna if known. The survey-in process may be performed during discontinuous (on/off low duty-cycle)
operation if necessary. In this case the receiver should be allowed to make several fixes during each cycle to
avoid excessive degradation of the survey-in accuracy.
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Time Mode Settings
Description
Disabled
Standard PVT operation
Survey-In
The receiver computes the average position over an extended time period until a predefined standard
deviation has been reached and the minimum observation time has passed by. Afterwards the receiver
will be automatically set to Fixed Mode and the timing features will be activated. Progress during survey
in can be monitored using the TIM-SVIN message.
Fixed Mode
Fixed Mode is initiated automatically at the completion of a survey-in process or when the receiver is
configured with its 3D position (and standard deviation of uncertainty). Fixed position coordinates can be
entered in ECEF (Earth Center Earth Fixed format) or as latitude, longitude and height.
Table 4: Time mode settings
A constellation-specific variant of Universal Coordinated Time (UTC) is used as the receiver's basis for conversion
from native GNSS time to UTC. The selection is explicitly specified in message CFG-NAV5. This is significant
when the time-pulse output has been configured (CFG-TP5) to be aligned with UTC rather than a GNSS time. In
this case, a version of UTC should be selected in CFG-NAV5 of which the receiver has knowledge (from aiding
messages or from the GNSS signals themselves). Other selections may result in relatively large timing
uncertainties until the offset between GNSS time and the selected UTC becomes available (from satellite signals
or aiding messages).
For more information see the u-blox 8 /u-blox M8 Receiver Description Including Protocol Specification [3].
1.8.2 Timepulse and frequency outputs
The NEO-M8T and LEA-M8T modules provide two time pulse outputs that can be configured in rate from
0.25 Hz up to 10 MHz by message CFG-TP5. Time pulse alignment can be configured to UTC or GNSS time
according to the standard used in signals being received or to an alternate standard where inter-standard
calibration data is available (from the signals themselves or by aiding). The time pulses are generated on edges of
an asynchronous clock; for pulse rates below 2 Hz, the exact phase of the TIMEPULSE output is reported before
each pulse in the TIM-TP message.
Times reported in navigation messages such as NAV-PVT report the time of the preceding pulse.
1.8.3 Time mark
The NEO-M8T and LEA-M8T modules can be used for precise time measurements with sub-microsecond
resolution using the external interrupt pins (EXTINT0 and EXTINT1). Rising and falling edges of these signals
are time-stamped to GNSS or UTC time, counted and the results reported in message TIM-TM2. The reference
time is the same as set for TIMEPULSE with CFG-TP5.
For more information see the u-blox 8 / u-blox M8 Receiver Description Including Protocol Specification
[3].
1.8.4 Timing integrity and availability
The NEO-M8T and LEA-M8T modules include the following measures to support applications requiring excellent
timing integrity:
Time uncertainty estimation
The receiver estimates the uncertainty of the time-pulse and time report based on the observed signal
characteristics. The time and uncertainties are reported together for each standards-specific time-base in
NAV-TIME messages. Under poor signal conditions the estimate of uncertainty may include unresolved
ambiguities; for example for GPS these might be Epoch (millisecond), Bit (20 ms) and Sub-frame (6 s). Where
the output time-base standard is derived from a different constellation (e.g. GPS-time from GLONASS), the
estimate of uncertainty includes inter-constellation offset uncertainties. The estimate of uncertainty is used
to disable or modify the time-pulse output by comparison with the tAcc parameter (after conversion to
distance) configured in message CFG-NAV5.
Multi-GNSS signal reception
Particularly where sky-view is limited, the timing accuracy is improved by combining measurements from two
constellations. Inter-GNSS timing offsets are derived locally by the receiver whenever a timing fix can be
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achieved independently from each constellation (locally derived offsets automatically account for antenna,
filter and cable dispersion). These offsets are then used for subsequent combined fixes. Where inter-GNSS
offsets cannot be derived locally, offsets broadcast by the constellation satellites are used where available.
Fix redundancy (RAIM)
The receiver automatically and continually adjusts the significance of individual signal measurements in the
reported estimate of time according to its quality and consistency. This ensures that the integrity of the
reported time is protected from individual faulty signals or measurements so long as there are more signals
in use than the minimum required. The minimum number changes depending on the situation but
whenever it is exceeded raim active is set in message TIM-TP to indicate that this protection is active.
Aiding
While a GNSS receiver may be able to achieve a vernier (sub-microsecond) time-fix even under poor signal
conditions it may be slow or unable to resolve higher order ambiguities (especially whole milliseconds for
GPS). Sub-millisecond time aiding may be applied to u-blox NEO-M8T and LEA-M8T modules by means of a
pulse to one of the EXTINT pins in conjunction with a MGA-INI-TIME message, enabling immediate
resolution of ambiguities as well as accelerating time to fix.
1.8.5 Raw Data
The NEO/LEA-M8T modules provide raw measurement data for civil L1 band GPS, GLONASS and BeiDou signals
including pseudo-range and carrier phase, Doppler and message payloads. The data contained in the RXM-
RAWX message follows the conventions of a multi-GNSS RINEX 3 observation file and includes pseudo-range,
carrier phase and Doppler measurements along with measurement quality data. The RXM-SFRBX message
provides the demodulated, parity-checked navigation and signaling message bits for each satellite currently
tracked by the receiver including GPS, GLONASS and BeiDou constellations, SBAS satellites, the QZSS L1S signal
and IMES beacons.
Raw measurement data are available once the receiver has established data bit synchronization and time-of-
week. Message data are available for all signals tracked at a sufficient level to achieve data bit and frame
synchronization. For more information see the u-blox 8 / M8 Receiver Description Including Protocol Specification
[3].
1.8.6 Low duty cycle operation
The NEO-M8T and LEA-M8T low power timing modules support energy-saving automatic on/off interval low
duty-cycle operation in conjunction with their precision timing features. On/off low duty-cycle operation is
enabled with the Power Save Mode setting in message CFG-RXM and on/off mode in message CFG-PM2.
Through a set of period and time-out parameters defined in the CFG-PM2 message the receiver can be
configured to deliver a new time fix at intervals with a limit on total energy consumed for searches if no fix can
be achieved. Note that the time-pulse output is not available while the receiver is in the off section of each
cycle.
The duty-cycle of operation may be reduced significantly by:
provision of sub-millisecond time-aiding to accelerate ambiguity resolution (see 1.8.4 above),
provision of ephemeris aiding (message MGA-GPS-EPH) to avoid the need to receive new data transmissions
from the satellites themselves.
Survey-in is supported in conjunction with low duty cycle operation providing the accuracy benefits of a long
observation interval without the need to keep the receiver continuously powered. To achieve the best sensitivity
on first deployment at a new site, the receiver should be allowed to operate continuously until the first fix is
achieved (up to 20 minutes in very poor signal conditions) before engaging low duty cycle operation.
For more information see the u-blox 8 / u-blox M8 Receiver Description Including Protocol Specification
[3].
1.9 TIMEPULSE
Two configurable time pulse signals (TIMEPULSE, TIMPULSE2) are available with u-blox NEO-M8T and LEA-
M8T timing modules. The TIMEPULSE outputs generate pulse trains synchronized with GNSS or UTC time grid
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with intervals configurable over a wide frequency range. Thus it may be used as a low frequency time
synchronization pulse or as a high frequency reference signal.
The TIMEPULSE2 (TP2) pin should not be held LO during start-up.
By default the primary time pulse signal is enabled and configured to 1 pulse per second. For more information
see the u-blox 8 / u-blox M8 Receiver Description including Protocol Specification [3].
1.10 Odometer
The odometer provides information on travelled ground distance (in meters) using solely the position and
Doppler-based velocity of the navigation solution. For each computed travelled distance since the last odometer
reset, the odometer estimates a 1-sigma accuracy value. The total cumulative ground distance is maintained and
saved in the BBR memory.
The odometer feature is disabled by default. For more details see the u-blox 8 / u-blox M8 Receiver
Description Including Protocol Specification [3].
1.11 Data logging
The u-blox NEO-M8T and LEA-M8T receivers can be used in data logging applications. The data logging feature
enables continuous storage of position, velocity and time information to an onboard SQI flash memory. It can
also log the distance from the odometer. The information can be downloaded from the receiver later for further
analysis or for conversion to a mapping tool. For more information see the u-blox 8 / u-blox M8 Receiver
Description Including Protocol Specification [3].
1.12 Geofencing
The u-blox NEO-M8T and LEA-M8T modules support up to four circular geofencing areas defined on the Earth’s
surface using a 2D model. Geofencing is active when at least one geofence is defined, the current status can be
found by polling the receiver. A GPIO pin can be nominated to indicate status or wake up a host on activation.
1.13 Message Integrity Protection
The NEO-M8T and LEA-M8T provide a function to detect third party interference with the UBX message stream
sent from receiver to host. The security mechanism signs nominated messages via a subsequent UBX message.
This message signature is then compared with one generated by the host to determine if the message data has
been altered.
1.14 Spoofing Detection
Spoofing is a process whereby a malicious third party tries to control the reported position via a fake GNSS
broadcast signal. This may result in the form of reporting incorrect position, velocity or time. To combat against
this, the NEO-M8T and LEA-M8T modules include spoofing detection measures to alert the host when signals
appear to be suspicious. The receiver combines a number of checks on the received signals looking for
inconsistencies across several parameters.
1.15 EXTINT: External interrupt
The NEO-M8T and LEA-M8T receivers feature two EXTINT pins, each of which can be used to switch the receiver
on and off or for aiding.
For more information about how to implement and configure these features, see the u-blox 8 / u-blox M8
Receiver Description including Protocol Specification [3] and the relevant Hardware Integration Manual [1] or [2].
1.15.1 Power control
The power control feature allows overriding the automatic active / inactive cycle of Power Save Mode. The state
of the receiver can be controlled through an EXTINT pin.
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The receiver can also be forced OFF using EXTINT when Power Save Mode is not active.
1.15.2 Aiding
An EXTINT pin can be used to supply time or frequency aiding data to the receiver.
For time aiding, hardware time synchronization can be achieved by connecting an accurate time pulse to the
EXTINT pin.
Frequency aiding can be implemented by connecting a periodic rectangular signal with a frequency up to
500 kHz and arbitrary duty cycle (low/high phase duration must not be shorter than 50 ns) to an EXTINT pin. The
applied frequency value is provided to the receiver using UBX messages.
For more information see the u-blox 8 / u-blox M8 Receiver Description Including Protocol Specification
[3].
1.16 Protocols and interfaces
Protocol
Type
NMEA 0183, version 4.0 (V2.3 or V4.1 configurable)
Input/output, ASCII, 0183, version 4.0
UBX
Input/output, binary, u-blox proprietary
RTCM
Input message, 1, 2, 3, 9
Table 5: Available Protocols
All protocols are available on UART, USB, DDC (I2C compliant) and SPI. For specification of the various protocols
see the u-blox 8 / u-blox M8 Receiver Description Including Protocol Specification [3].
1.17 Interfaces
A number of interfaces are provided for data communication. The embedded firmware uses these interfaces
according to their respective protocol specifications.
1.17.1 UART
The NEO-M8T and LEA-M8T modules include one UART interface, which can be used for communication to a
host. It supports configurable baud rates. For supported baud rates see the u-blox 8 / u-blox M8 Receiver
Description Including Protocol Specification [3].
Designs must allow access to the UART and the SAFEBOOT_N function pin for future service, updates
and reconfiguration.
1.17.2 USB
A USB interface, which is compatible to USB version 2.0 FS (Full Speed, 12 Mbit/s), can be used for
communication as an alternative to the UART. The pull-up resistor on pin USB_DP is integrated to signal a full-
speed device to the host. The VDD_USB pin supplies the USB interface. The u-blox USB (CDC-ACM) driver
supports Windows Vista plus Windows 7 and 8 operating systems. A separate driver (CDC-ACM) is not required
for Windows 10 which has a built-in USB-serial driver. However, plugging initially into an internet connected
Windows 10 PC, will down-load the u-blox combined sensor and VCP driver package.
USB drivers can be down-loaded from the u-blox web site, www.u-blox.com.
1.17.3 SPI
The SPI interface is designed to allow communication to a host CPU. The interface can be operated in slave
mode only. The maximum transfer rate using SPI is 125 kB/s and the maximum SPI clock frequency is 5.5 MHz
(see Figure 5). Note that SPI is not available in the default configuration, because its pins are shared with the
UART and DDC interfaces. The SPI interface can be enabled by connecting D_SEL (Pin 2) to ground (see section
3.1)
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1.17.4 Display Data Channel (DDC)
An I2C compliant DDC interface is available for communication with an external host CPU or u-blox cellular
modules. The interface can be operated in slave mode only. The DDC protocol and electrical interface are fully
compatible with Fast-Mode of the I2C industry standard. Since the maximum SCL clock frequency is 400 kHz, the
maximum transfer rate is 400 kb/s.
1.18 Clock generation
1.18.1 Oscillators
The NEO-M8T and LEA-M8T GNSS timing modules incorporate a TCXO for accelerated weak signal acquisition
and stable timing output. The TCXO is carefully selected and screened for stability and against frequency
perturbations across the full operating range (40° to +85°C).
1.18.2 Real-Time Clock (RTC) and Hardware Backup mode
The RTC can be maintained by a secondary 32 kHz oscillator using an RTC crystal. If the main supply voltage is
removed, a battery connected to V_BCKP allows the RTC to continue to run with very low power consumption.
The same supply also maintains a static back-up memory for current configuration information, recent
ephemeris, location and auxiliary data necessary to ensure the fastest re-acquisition when the primary power
supply is restored.
1.19 Power management
u-blox GNSS Timing product technology offers a power-optimized architecture with built-in autonomous power
saving functions to minimize power consumption at any given time. Furthermore, the receivers can be used in
three operating modes: Continuous mode for best performance or one of two Power Save Modes for optimized
power consumption. A high efficiency DC/DC converter is integrated to minimize power consumption and
dissipation across the range of supported power supply voltages.
For best GNSS performance use the Power Management Setup message UBX-CFG-PMS to configure Full
Power mode.
1.19.1 Operating modes
The NEO-M8T and LEA-M8T modules have two operating modes:
Continuous Mode for best GNSS performance
On/off duty-cycle Mode to reduce energy-use in discontinuous operation
Timing and raw data features are not fully supported in Cyclic Power Save Mode. There is limited support
for GLONASS, BeiDou and Galileo signals in On/off duty-cycle mode, notably in efficient reception and use
of ephemeris data.
1.19.1.1 Continuous Mode
Continuous Mode uses the acquisition engine at full performance resulting in the shortest possible TTFF and the
highest sensitivity. It searches for all possible satellites until the Almanac is completely downloaded. The receiver
then switches to the tracking engine to lower power consumption.
Thus, a lower tracking current consumption level will be achieved when:
A valid GNSS position is obtained
The entire Almanac has been downloaded
The Ephemeris for each satellite in view is valid
1.19.1.2 On/off Interval Power Save Mode
Where an application requires only intermittent navigation or timing information an On/off low duty-cycle power
save mode can be employed. In this mode the receiver starts at intervals configurable between a few seconds
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and several hours. Alternatively the receiver can be re-started on demand by a hardware signal applied to either
EXTINT input or activity on the UART. An EXTINT pin can also be configured (by CFG-PM2) to define durations
when the receiver should be held on or off by hardware control.
With each start, the receiver stays on for long enough to deliver a new fix or down-load new ephemeris if
necessary to make a fix. The receiver makes use of one or more of the following sources of aiding to reduce the
duration of each fix and thereby minimize overall energy use:
built-in RTC (time-aiding) or fine time-aiding delivered to an EXTINT pin (see MGA-INI-TIME messages)
last known or fixed position (see MGA-INI and CFG-TMODE2 messages)
ephemeris and auxiliary aiding data messages (see MGA-GPS, MGA-GLO and MGA-BDS messages)
On/off duty-cycle Power Save Mode may not provide the minimum energy use when GLONASS, BeiDou or
Galileo signal reception is enabled without ephemeris aiding.
For more information about power management strategies, see the u-blox 8 / u-blox M8 Receiver
Description Including Protocol Specification [3].
1.20 Antenna
1.20.1 Antenna type
The NEO-M8T includes a SAW filter and an additional LNA and is suitable for use with both passive
10
and active
11
antennas. The LEA-M8T includes a SAW filter and is suitable for use with active antennas and antenna
distribution systems. Within the recommended range below, lower overall gain can improve immunity to
interference in most situations; higher gain offers slightly better sensitivity.
Parameter
Specification
Antenna Type
Passive and active antenna
Active Antenna Recommendations
Minimum gain
Maximum gain
Maximum noise figure
5 dB (at module input)
40 dB12 (at module input)
1.5 dB
Table 6: Antenna Specifications
1.20.2 Antenna supervision
The LEA-M8T includes a built in antenna bias supply for nominal 3 V antennas enabled by linking the filtered
VCC_RF supply output pin to the V_ANT antenna supply input pin with a series resistor. The module then
controls the power supply to the antenna, applying power whenever the receiver is active and removing power
during power-save idle times and if a short-circuit is detected. Short-circuit is detected if the voltage at the
antenna supply falls close to zero and is indicated as an alarm in message MON-HW.
Optionally the EXTINT1 pin may be reassigned to antenna supervision, allowing an external circuit to indicate to
the module that the antenna is open-circuit. This condition is then reported in message MON-HW.
The NEO-M8T provides a control output for an external antenna supply switch. Antenna supervision is
configurable in both modules using message CFG-ANT.
Antenna supervision is configurable in both modules using message CFG-ANT.
For more details on antenna supervision in NEO-M8T or LEA-M8T see the relevant Hardware Integration
Manual [1] or [2].
10
For integration of M8T modules with Cellular products, see the NEO-8Q / NEO-M8 Hardware Integration Manual [1].
11
For information on using active antennas with NEO-M8T modules, see the NEO-8Q / NEO-M8 Hardware Integration Manual [1].
12
Gain above 20 dB should be avoided unless interference in the band 1463 MHz to 1710 MHz is adequately controlled.
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2 Pin definition
2.1 NEO-M8T pin assignment
Figure 3: NEO-M8T Pin Assignment
No
Name
I/O
Description
1
TP2/SAFEBOOT_N
I/O
Timepulse 2 / SAFEBOOT_N (for future service, updates and reconfiguration, must not
be held LO during start-up)
2
D_SEL
I
Interface select
3
TIMEPULSE
O
Time pulse (1PPS)
4
EXTINT0
I
External Interrupt Pin 0
5
USB_DM
I/O
USB Data
6
USB_DP
I/O
USB Data
7
VDD_USB
I
USB Supply
8
RESET_N
I
RESET_N
9
VCC_RF
O
Output Voltage RF section
10
GND
I
Ground
11
RF_IN
I
GNSS signal input
12
GND
I
Ground
13
GND
I
Ground
14
LNA_EN13
O
Enable external LNA / Antenna control
15
EXTINT1
I
External Interrupt Pin 1
16
Reserved
-
Reserved
17
Reserved
-
Reserved
18
SDA
SPI CS_N
I/O
DDC Data if D_SEL =1 (or open)
SPI Chip Select if D_SEL = 0
19
SCL
SPI CLK
I/O
DDC Clock if D_SEL =1(or open)
SPI Clock if D_SEL = 0
20
TXD
SPI MISO
O
Serial Port if D_SEL =1(or open)
SPI MISO if D_SEL = 0
21
RXD
SPI MOSI
I
Serial Port if D_SEL =1(or open)
SPI MOSI if D_SEL = 0
22
V_BCKP
I
Backup voltage supply
23
VCC
I
Supply voltage
24
GND
I
Ground
Table 7: NEO-M8T Pinout
Pins designated Reserved should not be used. For more information about Pinouts see the NEO-8Q /
NEO-M8 Hardware Integration Manual [1].
13
Compatible with pin labelled ANT_ON in predecessor products
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2.2 LEA-M8T pin assignment
Figure 4: LEA-M8T Pin Assignment
No
Name
I/O
Description
1
SDA
SPI CS_N
I/O
DDC Data if D_SEL =1 (or open)
SPI Chip Select if D_SEL = 0
2
SCL
SPI CLK
I/O
DDC Clock if D_SEL =1(or open)
SPI Clock if D_SEL = 0
3
TXD
SPI MISO
O
Serial Port if D_SEL =1(or open)
SPI MISO if D_SEL = 0
4
RXD
SPI MOSI
I
Serial Port if D_SEL =1(or open)
SPI MOSI if D_SEL = 0
5
D_SEL
I
Interface Select
6
VCC
I
Supply voltage
7
GND
-
Ground
8
VCC_OUT
O
Output Voltage (VCC)
9
Reserved
-
Reserved
10
RESET_N
I
RESET_N
11
V_BCKP
I
Backup voltage supply
12
TP2/SAFEBOOT_N
I/O
Timepulse 2 / SAFEBOOT_N (must not be held LO during start-up)
13
GND
-
Ground
14
GND
-
Ground
15
GND
-
Ground
16
RF_IN
I
GPS signal input
17
GND
-
Ground
18
VCC_RF
O
Output Voltage RF section
19
V_ANT
I
Active Antenna Voltage Supply
20
EXTINT114
I
External Interrupt Pin 1, can be configured as active antenna open circuit detection
pin: ANT_DET_N
21
Reserved
-
Reserved
22
Reserved
-
Reserved
23
Reserved
-
Reserved
24
VDD_USB
I
USB Supply
25
USB_DM
I/O
USB Data
26
USB_DP
I/O
USB Data
27
EXTINT0
I
External Interrupt Pin 0
28
TIMEPULSE
O
Timepulse (1 PPS)
Table 8: LEA-M8T Pinout
Pins designated Reserved should not be used. For more information about Pinouts see the LEA-M8S / M8T
Hardware Integration Manual [2].
14
Compatible with pin labelled AADET_N/EXTINT1 in predecessor products
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3 Configuration management
Configuration settings can be modified with UBX configuration messages. The modified settings remain effective
until power-down or reset. Settings can also be saved in battery-backed RAM, Flash or both using the UBX-CFG-
CFG message. If settings have been stored in battery-backed RAM then the modified configuration will be
retained as long as the backup battery supply is not interrupted. Settings stored in Flash memory will remain
effective even after power-down and do not require backup battery supply.
3.1 Interface selection (D_SEL)
At startup, the D_SEL pin determines which data interfaces are used for communication. If D_SEL is set high or
left open, UART and DDC become available. If D_SEL is set low, i.e. connected to ground, the modules can
communicate to a host via SPI.
PIN NUMBER
NEO-M8T
PIN NUMBER
LEA-M8T
D_SEL=”1”
(left open)
D_SEL =”0”
(connected to GND)
20
3
UART TX
SPI MISO
21
4
UART RX
SPI MOSI
19
2
DDC SCL
SPI CLK
18
1
DDC SDA
SPI CS_N
Table 9: Data interface selection by D_SEL
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4 Electrical specification
The limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress
above one or more of the limiting values may cause permanent damage to the device. These are stress
ratings only and operation of the device at these or at any other conditions above those given in the
characteristics sections of the specification is not implied. Exposure to these limits for extended periods
may affect device reliability.
Where application information is given, it is advisory only and does not form part of the specification. For
more information see the NEO-8Q / NEO-M8 Hardware Integration Manual [1] and LEA-M8S / M8T
Hardware Integration Manual [2].
4.1 Absolute maximum rating
Parameter
Symbol
Module
Condition
Min
Max
Units
Power supply voltage
VCC
All
0.5
3.6
V
Backup battery voltage
V_BCKP
All
0.5
3.6
V
USB supply voltage
VDD_USB
All
0.5
3.6
V
Input pin applied DC voltage
Vin
All
0.5
3.6
V
Vin_usb
All
0.5
VDD_USB
V
Vrfin
NEO-M8T
LEA-M8T15
0
-
0
-
V
DC current trough any digital I/O pin
(except supplies)
Ipin
10
mA
VCC_RF output current
ICC_RF
All
100
mA
Input power at RF_IN
Prfin
All
source impedance
= 50 ,
continuous wave
13
dBm
Antenna bias voltage
V_ANT
6
V
Antenna bias current
I_ANT
100
mA
Storage temperature
Tstg
All
40
85
°C
Table 10: Absolute maximum ratings
Stressing the device beyond the “Absolute Maximum Ratings” may cause permanent damage.
These are stress ratings only. The product is not protected against overvoltage or reversed
voltages. If necessary, voltage spikes exceeding the power supply voltage specification, given in
table above, must be limited to values within the specified boundaries by using appropriate
protection diodes.
15
Antenna bias is supplied by LEA-M8T module
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4.2 Operating conditions
All specifications are at an ambient temperature of 25°C. Extreme operating temperatures can
significantly impact specification values. Applications operating near the temperature limits should be
tested to ensure the specification.
Parameter
Symbol
Module
Min
Typical
Max
Units
Condition
Power supply voltage
VCC
All
2.7
3.0
3.6
V
Supply voltage USB
VDDUSB
All
3.0
3.3
3.6
V
Backup battery voltage
V_BCKP
All
1.4
3.6
V
Backup battery current
I_BCKP
NEO-M8T
15
µA
V_BCKP = 1.8 V,
VCC = 0 V
LEA-M8T
17
SW backup current
I_SWBCKP
NEO-M8T
30
µA
VCC = 3 V
LEA-M8T
50
Input pin voltage range
Vin
All
0
VCC+0.5
V
Digital IO Pin Low level input voltage
Vil
All
0
0.2*VCC
V
Digital IO Pin High level input voltage
Vih
All
0.7*VCC
VCC
V
Digital IO Pin Low level output voltage
Vol
All
0.4
V
Iol = 4 mA
Digital IO Pin High level output voltage
Voh
All
VCC0.4
V
Ioh = 4 mA
Pull-up resistor for RESET_N (internal)
Rpu
All
11
k
USB_DM, USB_DP
VinU
All
Compatible with USB with 27 series resistance
V_ANT antenna bias voltage
V_ANT
LEA-M8T
2.7
5.5
V
IANT < 50 mA
Antenna bias voltage drop
V_ANT_DROP
LEA-M8T
0.1
V
ICC_RF =50 mA
VCC_RF voltage
VCC_RF
All
VCC0.1
V
VCC_RF output current
ICC_RF
All
50
mA
Receiver Chain Noise Figure 16
NFtot
NEO-M8T
2.0
dB
LEA-M8T
4.7
Operating temperature
Topr
All
40
85
°C
Table 11: Operating conditions
Operation beyond the specified operating conditions can affect device reliability.
4.3 Indicative current requirements
Table 12 lists examples of the total system supply current for a possible application.
Values in Table 12 are provided for customer information only as an example of typical power
requirements. Values are characterized on samples, actual power requirements can vary depending on FW
version used, external circuitry, number of SVs tracked, signal strength, type of start as well as time,
duration and conditions of test.
Parameter
Symbol
Module
Typ
GPS
Typ
GPS / GLONASS /
QZSS / SBAS
Max
Units
Condition
Max. supply current 17
Iccp
All
67
mA
Average supply current 18, 19
Icc
NEO-M8T
25
32
mA
Estimated at 3 V
LEA-M8T
21
28
mA
Table 12: Indicative power requirements at VCC = 3.0 V
16
Only valid for the GPS band
17
Use this figure to dimension maximum current capability of power supply. Measurement of this parameter with 1 Hz bandwidth.
18
Use this figure to determine required battery capacity.
19
Simulated GNSS constellation using power levels of -130 dBm. VCC = 3.0 V
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For more information about power requirements, see the relevant M8T Hardware Integration Manual [1]
or [2].
For more information on how to noticeably reduce current consumption, see the Power Management
Application Note [5].
4.4 SPI timing diagrams
In order to avoid incorrect operation of the SPI, the user needs to comply with certain timing conditions. The
following signals need to be considered for timing constraints:
Symbol
Description
SPI CS_N (SS_N)
Slave select signal
SPI CLK (SCK)
Slave clock signal
Table 13: Symbol description
Figure 5: SPI timing diagram
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4.4.1 Timing recommendations
The recommendations below are based on a firmware running from Flash memory.
Parameter
Description
Recommendation
tINIT
Initialization Time
>10 s
tDES
Deselect Time
1 ms.
tbit
Minimum bit time
180 ns (5.5 MHz max bit frequency)
tbyte
Minimum byte period
8 s (125 kHz max byte frequency)
Table 14: SPI timing recommendations
The values in the above table result from the requirement of an error-free transmission. By allowing just a
few errors and disabling the glitch filter, the bit rate can be increased considerably.
4.5 DDC timing diagrams
The DDC interface is I2C Fast Mode compliant. For timing parameters consult the I2C standard.
The maximum bit rate is 400 kb/s. The interface stretches the clock when slowed down when serving
interrupts, so real bit rates may be slightly lower.
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5 Mechanical specifications
5.1 NEO-M8T
Figure 6: Dimensions
For information about the paste mask and footprint, see the NEO-8Q / NEO-M8 Hardware Integration
Manual [1].
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5.2 LEA-M8T
Figure 7: LEA Dimensions
For information about the paste mask and footprint, see the LEA-M8S / M8T Hardware Integration
Manual [2].
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6 Reliability tests and approvals
6.1 Reliability tests
The NEO-M8T and LEA-M8T modules are based on AEC-Q100 qualified GNSS chips.
Tests for product family qualifications are according to ISO 16750 "Road vehicles environmental conditions
and testing for electrical and electronic equipment”, and appropriate standards.
6.2 Approvals
Products marked with this lead-free symbol on the product label comply with the
"Directive 2002/95/EC of the European Parliament and the Council on the Restriction of
Use of certain Hazardous Substances in Electrical and Electronic Equipment" RoHS).
All u-blox M8 GNSS modules are RoHS compliant.
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7 Product handling & soldering
7.1 Packaging
NEO-M8T and LEA-M8T GNSS modules are delivered as hermetically sealed, reeled tapes in order to enable
efficient production, production lot set-up and tear-down. For more information see the u-blox Package
Information Guide [4].
7.1.1 Reels
NEO-M8T and LEA-M8T GNSS modules are both deliverable in quantities of 250 pcs on a reel. NEO-M8T and
LEA-M8T receivers are shipped on Reel Type B, as specified in the u-blox Package Information Guide [4].
7.1.2 NEO-M8T Tapes
The dimensions and orientations of the tapes for NEO-M8T modules are specified in Figure 8.
Figure 8: Dimensions and orientation for NEO-M8T modules on tape
NEO/LEA-M8T - Data Sheet
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7.1.3 LEA-M8T Tapes
The dimensions and orientations of the tapes for LEA-M8T modules are specified in Figure 9.
Pin 1 Sprocket Hole
Feed direction
Figure 9: Dimensions and orientation for LEA-M8T modules on tape
7.2 Shipment, storage and handling
For important information regarding shipment, storage and handling see the u-blox Package Information Guide
[4].
7.2.1 Moisture sensitivity levels
The Moisture Sensitivity Level (MSL) relates to the packaging and handling precautions required. NEO-M8T and
LEA-M8T modules are rated at MSL level 4.
For MSL standard see IPC/JEDEC J-STD-020, which can be downloaded from www.jedec.org.
For more information regarding MSL see the u-blox Package Information Guide [4].
7.2.2 Reflow soldering
Reflow profiles are to be selected according u-blox recommendations (see the relevant Hardware Integration
Manual [1] or [2]).
NEO/LEA-M8T - Data Sheet
UBX-15025193 - R03 Production Information Product handling & soldering
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7.2.3 ESD handling precautions
NEO-M8T and LEA-M8T modules are Electrostatic Sensitive Devices (ESD). Observe precautions
for handling! Failure to observe these precautions can result in severe damage to the GNSS
receiver!
GNSS receivers are Electrostatic Sensitive Devices (ESD) and require special precautions when handling. Particular
care must be exercised when handling patch antennas, due to the risk of electrostatic charges. In addition to
standard ESD safety practices, the following measures should be taken into account whenever handling the
receiver:
Unless there is a galvanic coupling between the
local GND (i.e. the work table) and the PCB GND,
then the first point of contact when handling the
PCB must always be between the local GND and
PCB GND.
Before mounting an antenna patch, connect
ground of the device
When handling the RF pin, do not come into
contact with any charged capacitors and be
careful when contacting materials that can
develop charges (e.g. patch antenna ~10 pF, coax
cable ~50-80 pF/m, soldering iron, …)
To prevent electrostatic discharge through the RF
input, do not touch any exposed antenna area. If
there is any risk that such exposed antenna area is
touched in non ESD protected work area,
implement proper ESD protection measures in the
design.
When soldering RF connectors and patch
antennas to the receiver’s RF pin, make sure to
use an ESD safe soldering iron (tip).
NEO/LEA-M8T - Data Sheet
UBX-15025193 - R03 Production Information Default messages
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8 Default messages
Interface
Settings
UART Output
9600 Baud, 8 bits, no parity bit, 1 stop bit
Configured to transmit both NMEA and UBX protocols, but only the following NMEA (and no UBX)
messages have been activated at start-up:
GGA, GLL, GSA, GSV, RMC, VTG, TXT, ZDA
USB Output
Configured to transmit both NMEA and UBX protocols, but only the following NMEA (and no UBX)
messages have been activated at start-up:
GGA, GLL, GSA, GSV, RMC, VTG, TXT, ZDA
USB Power Mode: Bus Powered
UART Input
9600 Baud, 8 bits, no parity bit, 1 stop bit, Autobauding disabled
Automatically accepts following protocols without need of explicit configuration:
UBX, NMEA, RTCM
The GNSS receiver supports interleaved UBX and NMEA messages.
USB Input
Automatically accepts following protocols without need of explicit configuration:
UBX, NMEA
The GPS receiver supports interleaved UBX and NMEA messages.
USB Power Mode: Bus Powered
DDC
Fully compatible with the I2C industry standard, available for communication with an external host CPU or
u-blox cellular modules, operated in slave mode only. Default messages activated.
NMEA and UBX are enabled as input messages, only NMEA as output messages.
Maximum bit rate 400 kb/s.
SPI
Allow communication to a host CPU, operated in slave mode only. Default messages activated. SPI is not
available in the default configuration.
TIMEPULSE
(1 Hz Nav)
1 pulse per second, synchronized at rising edge, pulse length 100 ms
Table 15: Default messages
Refer to the u-blox 8 / u-blox M8 Receiver Description Including Protocol Specification [3] for information
about further settings.
NEO/LEA-M8T - Data Sheet
UBX-15025193 - R03 Production Information Labeling and ordering information
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9 Labeling and ordering information
9.1 NEO-M8T product labeling
The labeling of u-blox M8 GNSS modules includes important product information. The location of the NEO-M8T
product type number is shown in Figure 10.
Figure 10: Location of product type number on u-blox NEO-M8T module label
9.2 LEA-M8T product labeling
The labeling of u-blox M8 GNSS modules includes important product information. The location of the LEA-M8T
product type number is shown in Figure 11.
Figure 11: Location of product type number on u-blox LEA-M8T module label
9.3 Explanation of codes
Three different product code formats are used. The Product Name is used in documentation such as this data
sheet and identifies all u-blox M8 products, independent of packaging and quality grade. The Ordering Code
includes options and quality, while the Type Number includes the hardware and firmware versions. Table 16
shows the structure of these three different formats.
Format
Structure
Product Name
PPP-TGV
Ordering Code
PPP-TGV-T
Type Number
PPP-TGV-T-XX
Table 16: Product Code Formats
NEO/LEA-M8T - Data Sheet
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Page 33 of 35
The parts of the product code are explained in Table 17.
Code
Meaning
Example
PPP
Product Family
NEO
TG
Platform
M8 = u-blox M8
V
Variant
Function set (A-Z), T = Timing, R = DR, etc.
T
Option / Quality Grade
Describes standardized functional element or quality grade
0 = Default variant, A = Automotive
XX
Product Detail
Describes product details or options such as hard- and software revision, cable length, etc.
Table 17: part identification code
9.4 Ordering codes
Ordering No.
Product
LEA-M8T-0
u-blox M8 GNSS Module, Timing, TCXO, flash, SAW, 17x22.4 mm, 250 pcs/reel
NEO-M8T-0
u-blox M8 GNSS Module, Timing, TCXO, flash, SAW, LNA, 12.2x16 mm, 250 pcs/reel
Table 18: Product ordering codes
Product changes affecting form, fit or function are documented by u-blox. For a list of Product Change
Notifications (PCNs) see our website.
NEO/LEA-M8T - Data Sheet
UBX-15025193 - R03 Production Information Related documents
Page 34 of 35
Related documents
[1] NEO-8Q / NEO-M8 Hardware Integration Manual, Doc. No. UBX-15029985
[2] LEA-M8S / LEA-M8T Hardware Integration Manual, Docu. No. UBX-15030060
[3] u-blox 8 / u-blox M8 Receiver Description Including Protocol Specification (Public version), Docu. No.
UBX-13003221
[4] u-blox Package Information Guide, Docu. No. UBX-14001652
[5] Power Management Application Note, Docu. No. UBX-13005162
[6] MGA Services User Guide, Docu. No. UBX-13004360
For regular updates to u-blox documentation and to receive product change notifications, register on our
website (http://www.u-blox.com).
Revision history
Revision
Date
Name
Status / Comments
R01
28-Oct-2015
amil
Objective Specification
R02
03-May-2016
amil
Advance Information
R03
21-Jun-2016
amil
Production Information, minor update in Table 1and Table 8, removed reference to message
UBX-CFG-TM2
NEO/LEA-M8T - Data Sheet
UBX-15025193 - R03 Production Information Contact
Page 35 of 35
Contact
For complete contact information visit us at www.u-blox.com
u-blox Offices
North, Central and South America
u-blox America, Inc.
Phone: +1 703 483 3180
E-mail: info_us@u-blox.com
Regional Office West Coast:
Phone: +1 408 573 3640
E-mail: info_us@u-blox.com
Technical Support:
Phone: +1 703 483 3185
E-mail: support_us@u-blox.com
Headquarters
Europe, Middle East, Africa
u-blox AG
Phone: +41 44 722 74 44
E-mail: info@u-blox.com
Support: support@u-blox.com
Asia, Australia, Pacific
u-blox Singapore Pte. Ltd.
Phone: +65 6734 3811
E-mail: info_ap@u-blox.com
Support: support_ap@u-blox.com
Regional Office Australia:
Phone: +61 2 8448 2016
E-mail: info_anz@u-blox.com
Support: support_ap@u-blox.com
Regional Office China (Beijing):
Phone: +86 10 68 133 545
E-mail: info_cn@u-blox.com
Support: support_cn@u-blox.com
Regional Office China (Chongqing):
Phone: +86 23 6815 1588
E-mail: info_cn@u-blox.com
Support: support_cn@u-blox.com
Regional Office China (Shanghai):
Phone: +86 21 6090 4832
E-mail: info_cn@u-blox.com
Support: support_cn@u-blox.com
Regional Office China (Shenzhen):
Phone: +86 755 8627 1083
E-mail: info_cn@u-blox.com
Support: support_cn@u-blox.com
Regional Office India:
Phone: +91 80 4050 9200
E-mail: info_in@u-blox.com
Support: support_in@u-blox.com
Regional Office Japan (Osaka):
Phone: +81 6 6941 3660
E-mail: info_jp@u-blox.com
Support: support_jp@u-blox.com
Regional Office Japan (Tokyo):
Phone: +81 3 5775 3850
E-mail: info_jp@u-blox.com
Support: support_jp@u-blox.com
Regional Office Korea:
Phone: +82 2 542 0861
E-mail: info_kr@u-blox.com
Support: support_kr@u-blox.com
Regional Office Taiwan:
Phone: +886 2 2657 1090
E-mail: info_tw@u-blox.com
Support: support_tw@u-blox.com

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