u-blox LEA-M8T, NEO-M8T User Manual

Abstract

Technical data sheet describing the NEO/LEA-M8T modules with concurrent reception of
GPS/QZSS, GLONASS, BeiDou, and Galileo. They provide optimized accuracy and availability with
survey-in and single-satellite timing. The modules feature market leading acquisition and tracking
sensitivity, minimized power consumption with low duty-cycle operation, and maximized reliability
with integrity monitoring and alarms.

www.u-blox.com

UBX-15025193 - R05

NEO/LEA-M8T

u-blox M8 concurrent GNSS timing modules

Data sheet

NEO/LEA-M8T - Data sheet

Title

NEO/LEA-M8T

Subtitle

u-blox M8 concurrent GNSS timing modules

Document type

Data sheet

Document number

UBX-15025193

Revision and date

R05

2-Jun-2020

Document status

Production Information

Product status

Corresponding content status

In development /
Prototype

Objective specification

Target values. Revised and supplementary data will be published later.

Engineering sample

Advance information

Data based on early testing. Revised and supplementary data will be published later.

Initial production

Early production information

Data from product verification. Revised and supplementary data may be published later.

Mass production /
End of life

Production information

Document contains the final product specification.

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-0-11

Flash FW 3.01 TIM 1.10

UBX-20013367

LEA-M8T

LEA-M8T-1-00

Flash FW 3.01 TIM 1.11

N/A

u-blox or third parties may hold intellectual property rights in the products, names, logos and designs included in this
document. Copying, reproduction, modification or disclosure to third parties of this document or any part thereof is only
permitted with the express written permission of u-blox.
The information contained herein is provided “as is” and u-blox assumes no liability for its use. No warranty, either express or
implied, is given, including but not limited to, 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 without notice. For the most recent
documents, visit www.u-blox.com.
Copyright © u-blox AG.

Document information

This document applies to the following products:

UBX-15025193 - R05 Document information Page 2 of 36
Production Information

NEO/LEA-M8T - Data sheet

Contents

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 AssistNow

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 ................................................................................................................................................ 14

1.10 Odometer .................................................................................................................................................... 14

1.11 Data logging ............................................................................................................................................... 14

1.12 Geofencing .................................................................................................................................................. 14

1.13 Message integrity protection ................................................................................................................. 14

1.14 Spoofing detection ................................................................................................................................... 15

1.15 EXTINT: External interrupt ...................................................................................................................... 15

1.15.1 Power control ..................................................................................................................................... 15

1.15.2 Aiding .................................................................................................................................................. 15

1.16 Protocols and interfaces ......................................................................................................................... 15

1.17 Interfaces .................................................................................................................................................... 15

1.17.1 UART ................................................................................................................................................... 16

1.17.2 USB ...................................................................................................................................................... 16

1.17.3 SPI ........................................................................................................................................................ 16

1.17.4 Display data channel (DDC) ............................................................................................................ 16

TM

Autonomous .............................................................................................................. 10

UBX-15025193 - R05 Contents Page 3 of 36
Production Information

NEO/LEA-M8T - Data sheet

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

1.19.2 Continuous mode .............................................................................................................................. 17

1.19.3 On/off interval power save mode ................................................................................................... 17

1.20 Antenna ....................................................................................................................................................... 18

1.20.1 Antenna type ..................................................................................................................................... 18

1.20.2 Antenna supervision ........................................................................................................................ 18

2 Pin definition ........................................................................................................................................ 19

2.1 NEO-M8T pin assignment ....................................................................................................................... 19

2.2 LEA-M8T pin assignment ....................................................................................................................... 20

3 Configuration management ............................................................................................................ 22

3.1 Interface selection (D_SEL) .................................................................................................................... 22

4 Electrical specification ..................................................................................................................... 23

4.1 Absolute maximum rating ....................................................................................................................... 23

4.2 Operating conditions ................................................................................................................................ 24

4.3 Indicative current requirements ............................................................................................................ 24

4.4 SPI timing diagrams ................................................................................................................................. 25

4.4.1 Timing recommendations ............................................................................................................... 25

4.5 DDC timing diagrams ............................................................................................................................... 25

5 Mechanical specifications ............................................................................................................... 26

5.1 NEO-M8T .................................................................................................................................................... 26

5.2 LEA-M8T ..................................................................................................................................................... 27

6 Reliability tests and approvals ....................................................................................................... 28

6.1 Reliability tests .......................................................................................................................................... 28

6.2 Approvals .................................................................................................................................................... 28

7 Product handling and soldering ..................................................................................................... 29

7.1 Packaging ................................................................................................................................................... 29

7.1.1 Reels .................................................................................................................................................... 29

7.1.2 NEO-M8T tapes ................................................................................................................................ 29

7.1.3 LEA-M8T tapes ................................................................................................................................. 30

7.2 Shipment, storage and handling ........................................................................................................... 30

7.2.1 Moisture sensitivity levels .............................................................................................................. 30

7.2.2 Reflow soldering ................................................................................................................................ 30

7.2.3 ESD handling precautions .............................................................................................................. 31

8 Default messages ............................................................................................................................... 32

9 Labeling and ordering information ............................................................................................... 33

9.1 NEO-M8T product labeling ..................................................................................................................... 33

9.2 LEA-M8T product labeling ...................................................................................................................... 33

9.3 Explanation of codes ................................................................................................................................ 34

UBX-15025193 - R05 Contents Page 4 of 36
Production Information

NEO/LEA-M8T - Data sheet

9.4 Ordering codes ........................................................................................................................................... 34

UBX-15025193 - R05 Contents Page 5 of 36
Production Information

NEO/LEA-M8T - Data sheet

Model

Category

GNSS

Supply

Interfaces

Features

Grade

Standard Precision GNSS

High Precision GNSS

Dead Reckoning Timing GPS / QZSS GLONASS

Galileo BeiDou Number of concurrent

GNSS

2.7 V

– 3.6 V

UART USB SPI

DDC (I

2

C compliant)

Programmable (flash) Data logging Carrier phase output Additional

SAW

Additional LNA VCTCXO Timepulse Frequency output Standard Professional Automotive

NEO-M8T

●

●

●

●

● 3 ●

●

●

●

●

●

●

●

●

● 2

●

LEA-M8T

●

●

●

●

● 3 ●

●

●

●

●

●

●

●

● 2 ●

C = Crystal / T = TCXO

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

UBX-15025193 - R05 Functional description Page 6 of 36
Production Information

NEO/LEA-M8T - Data sheet

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-First­Fix1

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°

0.3°

0.3°

0.4°

0.5°

0.5°

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

1

2

3

4

5

6

7

8

9

1.3 Performance

Table 1: NEO/LEA-M8T performance in different GNSS modes (default: concurrent reception of GPS and GLONASS)

All satellites at -130 dBm
Demonstrated with a good external LNA
Time: 1s, Position: 1km, Almanac, Ephemeris
CEP, 50%, 24 hours static, -130 dBm, > 6 SVs
To be confirmed when Galileo reaches full operational capability
50% at 30 m/s
Rates with SBAS disabled for > 98% fix report rate under typical conditions
1-sigma
Assuming Airborne < 4 g platform

UBX-15025193 - R05 Functional description Page 7 of 36
Production Information

NEO/LEA-M8T - Data sheet

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.

UBX-15025193 - R05 Functional description Page 8 of 36
Production Information

NEO/LEA-M8T - Data sheet

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.

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, 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.

UBX-15025193 - R05 Functional description Page 9 of 36
Production Information

NEO/LEA-M8T - Data sheet

1.6.1 AssistNow

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.

TM

Online

☞ The AssistNow Online service provides data for GPS, GLONASS, BeiDou, Galileo and QZSS.

1.6.2 AssistNow

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.

TM

Offline

☞ AssistNow Offline service provides data for GPS and GLONASS only, BeiDou and Galileo are not

currently supported.

1.6.3 AssistNow

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.

TM

Autonomous

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 the 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

UBX-15025193 - R05 Functional description Page 10 of 36
Production Information

NEO/LEA-M8T - Data sheet

Message type

Description

1

Differential GPS corrections

2

Delta differential GPS corrections

3

GPS reference station parameters

9

GPS partial correction set

in better availability especially under challenging signal conditions, for example, in urban canyons. The
L1- SAIF signal provided by QZSS can be enabled for reception via a GNSS configuration message.

1.7.3 IMES

The Japanese Indoor Messaging System (IMES) system is used for indoor position reporting using
low-power transmitters which broadcast a GPS–like 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:

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 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

UBX-15025193 - R05 Functional description Page 11 of 36
Production Information