Telit Wireless Solutions LE51-868 S User Manual

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LE51-868 S RF Module User Guide

1VV0301131 Rev.0 – 2014-01-16

LE51-868 S RF Module User Guide

1VV0301131Rev.0 – 2014-01-16

APPLICABILITY TABLE

PRODUCT

LE51-868 S

SPECIFICATIONS SUBJECT TO CHANGE WITHOut Notice

Notice

While reasonable efforts have been made to assure the accuracy of this document, Telit assumes no liability resulting from any inaccuracies or omissions in this document, or from use of the information obtained herein. The information in this document has been carefully checked and is believed to be entirely reliable. However, no responsibility is assumed for inaccuracies or omissions. Telit reserves the right to make changes to any products described herein and reserves the right to revise this document and to make changes from time to time in content hereof with no obligation to notify any person of revisions or changes. Telit does not assume any liability arising out of the application or use of any product, software, or circuit described herein; neither does it convey license under its patent rights or the rights of others.

It is possible that this publication may contain references to, or information about Telit products (machines and programs), programming, or services that are not announced in your country. Such references or information must not be construed to mean that Telit intends to announce such Telit products, programming, or services in your country.

LE51-868 S RF Module User Guide

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Copyrights

This instruction manual and the Telit products described in this instruction manual may be, include or describe copyrighted Telit material, such as computer programs stored in semiconductor memories or other media. Laws in the Italy and other countries preserve for Telit and its licensors certain exclusive rights for copyrighted material, including the exclusive right to copy, reproduce in any form, distribute and make derivative works of the copyrighted material. Accordingly, any copyrighted material of Telit and its licensors contained herein or in the Telit products described in this instruction manual may not be copied, reproduced, distributed, merged or modified in any manner without the express written permission of Telit. Furthermore, the purchase of Telit products shall not be deemed to grant either directly or by implication, estoppel, or otherwise, any license under the copyrights, patents or patent applications of Telit, as arises by operation of law in the sale of a product.

Computer Software Copyrights

The Telit and 3rd Party supplied Software (SW) products described in this instruction manual may include copyrighted Telit and other 3rd Party supplied computer programs stored in semiconductor memories or other media. Laws in the Italy and other countries preserve for Telit and other 3rd Party supplied SW certain exclusive rights for copyrighted computer programs, including the exclusive right to copy or reproduce in any form the copyrighted computer program. Accordingly, any copyrighted Telit or other 3rd Party supplied SW computer programs contained in the Telit products described in this instruction manual may not be copied (reverse engineered) or reproduced in any manner without the express written permission of Telit or the 3rd Party SW supplier. Furthermore, the purchase of Telit products shall not be deemed to grant either directly or by implication, estoppel, or otherwise, any license under the copyrights, patents or patent applications of Telit or other 3rd Party supplied SW, except for the normal non-exclusive, royalty free license to use that arises by operation of law in the sale of a product.

LE51-868 S RF Module User Guide

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Usage and Disclosure Restrictions License Agreements

The software described in this document is the property of Telit and its licensors. It is furnished by express license agreement only and may be used only in accordance with the terms of such an agreement.

Copyrighted Materials

Software and documentation are copyrighted materials. Making unauthorized copies is prohibited by law. No part of the software or documentation may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language or computer language, in any form or by any means, without prior written permission of Telit

High Risk Materials

Components, units, or third-party products used in the product described herein are NOT fault-tolerant and are NOT designed, manufactured, or intended for use as on-line control equipment in the following hazardous environments requiring fail-safe controls: the operation of Nuclear Facilities, Aircraft Navigation or Aircraft Communication Systems, Air Traffic Control, Life Support, or Weapons Systems (High Risk Activities"). Telit and its supplier(s) specifically disclaim any expressed or implied warranty of fitness for such High Risk Activities.

Trademarks

TELIT and the Stylized T Logo are registered in Trademark Office. All other product or service names are the property of their respective owners.

Contents

LE51-868 S RF Module User Guide

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1. Introduction ................................................. 7

1.1. Scope ..................................................... 7

1.2. Audience .................................................. 7

1.3. Contact Information, Support .............................. 7

1.4. Document Organization ..................................... 7

1.5. Text Conventions .......................................... 8

1.6. Related Documents ......................................... 9

2. Requirements ................................................ 10

2.1. General Requirements ..................................... 10

2.2. 868 MHz band Requirements ................................ 10

2.3. Other Requirements ....................................... 11

2.4. Functional Requirements .................................. 11

2.5. Software ................................................. 12

2.6. Temperature Requirements ................................. 12

3. General Characteristics ..................................... 13

3.1. Mechanical Characteristics ............................... 13

3.2. Mechanical dimensions .................................... 14

3.3. Recommended Land pattern ................................. 15

3.4. DC Characteristics ....................................... 15

3.5. LE51-868 S Functional Characteristics .................... 16

3.6. Digital Characteristic ................................... 18

3.7. Absolute Maximum Ratings ................................. 18

3.8. Ordering Information ..................................... 19

4. Technical Description ....................................... 21

4.1. Module Top View (cover side) ............................. 21

4.2. Pin-out of the module LE51-868 S ......................... 22

4.3. Pin-out of the DIP Interface ............................. 23

4.4. Pin-out correspondence table ............................. 24

4.5. Description of the signals ............................... 25

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5. Process Information ......................................... 26

5.1. Delivery ................................................. 26

5.2. Storage .................................................. 27

5.3. Soldering pad pattern .................................... 27

5.4. Solder past .............................................. 27

5.5. Placement ................................................ 28

5.6. Soldering Profile (RoHS Process) ......................... 28

6. Board Mounting Recommendation ............................... 30

6.1. Electrical environment ................................... 30

6.2. Power supply decoupling on LE51-868 S module ............. 30

6.3. RF layout considerations ................................. 31

6.4. Antenna connections on printed circuit boards ............ 32

6.5. LE51-868 S Interfacing ................................... 33

7. Safety Recommendations ...................................... 36

8. Glossary .................................................... 37

9. Document History ............................................ 38

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1. Introduction

1.1. Scope

Scope of this document is to present the features and the application of the Telit LE51-868 S radio modules.

1.2. Audience

This document is intended for developers using Telit LE51-868 S radio modules.

1.3. Contact Information, Support

For general contact, technical support, to report documentation errors and to order manuals, contact Telit Technical Support Center (TTSC) at:

TS-SRD@telit.com TS-NORTHAMERICA@telit.com TS-LATINAMERICA@telit.com TS-APAC@telit.com

Alternatively, use:

http://www.telit.com/en/products/technical-support-center/contact.php

For detailed information about where you can buy the Telit modules or for recommendations on accessories and components visit:

http://www.telit.com

To register for product news and announcements or for product questions contact Telit Technical Support Center (TTSC).

Our aim is to make this guide as helpful as possible. Keep us informed of your comments and suggestions for improvements.

Telit appreciates feedback from the users of our information.

1.4. Document Organization

This document contains the following chapters

“Chapter 1: “Introduction” provides a scope for this document, target audience, contact and

support information, and text conventions.

“Chapter 2: “Requirements” gives an overview of the limitations imposed by Reference

standards.

“Chapter 3: “General Characteristics” describes in detail the characteristics of the product.

“Chapter 4: “Technical Description” describes in detail the signals and pin-out of the product. “Chapter 5: “Process information” describes in detail the delivery, storage, soldering and

placement of the product.

“Chapter 6: “Board Mounting Recommendations” describes in detail the interface and

coupling of the product.

“Chapter 8: “Glossary” shows acronyms used in the document. “Chapter 9: “Document history” describes the revision history of the document.

1.5. Text Conventions

Danger – This information MUST be followed or catastrophic equipment failure or bodily injury may occur.

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Caution or Warning – Alerts the user to important points about integrating the module, if these points are not followed, the module and end user equipment may fail or malfunction.

Tip or Information – Provides advice and suggestions that may be useful when integrating the module.

All dates are in ISO 8601 format, i.e. YYYY-MM-DD.

1.6. Related Documents

• [1] EN 300 220-2 v2.4.1, ETSI Standards for SRD , May 2012

• [2] ERC Rec 70-03, ERC Recommendation for SRD, October 2012

• [3] 2002/95/EC, Directive of the European Parliament and of the Council, 27 January 2003

• [4] SR Tool User Guide, 1vv0300899

• [5] 2006/771/EC, Harmonization of the radio spectrum for use by short-range devices

• [6] 2009/381/EC, Amending Decision 2006/771/EC on harmonization of the radio

spectrum for use by short-range devices

• [7] Sigfox Stand-Alone Module User Guide, 1vv0301109

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Band g3

869.400

– 869.650

500 25 kHz or the whole band

2. Requirements

2.1. General Requirements

The LE51-868 S module is a multi-channel radio board, delivering up to 35 mW in the 868 MHz ISM band (unlicensed frequency band).

It is delivered with preloaded protocol stack:

• LE51-868 S SIGFOX™ Network Software.

LE51-868 S is pin-to-pin compatible with LE, NE and ME modules working at different frequencies.

LE51-868 S is also pin-to-pin compatible with Telit ZE Family (ZigBee 2007 and ZigBee PRO stack).

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2.2. 868 MHz band Requirements

The “ERC recommendation 70-03” describes the different usable sub-bands in the 868 MHz license free band, in terms of bandwidth, maximum power, duty cycle and channel spacing. LE51-868 S can operate on Annex 1, g1 band where “ERC recommendation 70-03” gives the following limitations:

ERC recommendation 70-03

Band Frequency band

(MHz)

Annex 1 g1 868.0 – 868.6 25 No channel spacing specified 1

This band is free to use but the module and the user must respect some limitations. Most of these restrictions are integrated in the conception of the module, except the duty cycle. For example, the g1 sub-band from 868.000 to 868.600 MHz band is limited to a 1% duty cycle. This means that each module is limited to a total transmit time of 36 seconds per hour. It is the responsibility of the user to respect the duty cycle. Sigfox has also a limitation on this band to ensure unsaturated network.

In order to fulfil the ETSI 70-03 specification requirement regarding duty cycle on ISM band and to be aligned with Sigfox network management, each hour the application can send up to 72 Bytes (e.g., 6 messages of 12 bytes each).

Maximum radiated power (mW)

Channel spacing (kHz)

Duty cycle (%)

Furthermore, the module complies with the ETSI 300-220-2 v2.3.1 standards (specific for SRD) whose main requirements are described in Appendix 1.

Finally, the module complies with the European Directive 2002/95/EC concerning the Restrictive Usage of Hazardous Substances (RoHS).

Country

Restriction

Reason/Remark

Spain

Limited implementation

to the band 863

868 MHz

The Netherlands

Not Implemented

Under stu

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National Restrictions for non specific SR devices Annex 1 band g1-g4:

Band G

Austria Not Implemented Planned Finland Limited Implementation

Audio, video and voice not allowed Planned 2011

Georgia Not Implemented

Sweden Not Implemented

Ukraine Limited implementation

Band G1

Georgia Russian Federation

Not Implemented Not Implemented

863-865 / 868-868.6 / 868.6-868.7 /

869.2-869.25 MHz

Ukraine Not Implemented e.i.r.p. ≤25 mW

2.3. Other Requirements

The module complies with the European Directive 2002/95/EC concerning the Restrictive Usage of Hazardous Substances (RoHS).

2.4. Functional Requirements

The LE51-868 S module is a complete solution from serial interface to RF interface. The LE51-868 module has a digital part and a RF part. The radio link on Sigfox network is a mono-directional link, since RX features are not required to be compliant with the network protocol.

The digital part has the following functionalities:

• Communication interface

• I/O management

• Micro controller with embedded Telit Software Stack supporting Sigfox protocol

The RF part has the following functionalities:

• Frequency synthesis

• Front-end

• Power amplification

Operating

LE51-868 S RF Module User Guide

• Packet handling

2.5. Software

The LE51-868 S module is provided pre-flashed with one of the available Telit in-house Protocol Stack.

Please refer to Protocol Stack User Guide [7] for detailed information.

2.6. Temperature Requirements

Minimum Typical Maximum Unit

Temperature - 40 25 + 85 °C Relative humidity @

25°C

Storage

Temperature - 40 25 + 85 °C

20 75 %

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3. General Characteristics

3.1. Mechanical Characteristics

Size :

Height :

Weight :

PCB thickness:

Cover* :

Components :

Connectors :

Mounting :

Number of pins :

Rectangular 25.8 x 15 mm

3 mm

1.7 g

0.8 mm

• Dimensions : 25 x 14.2 x 2.2mm

• Thickness : 200µm

All SMD components, on one side of the PCB.

The terminals allowing conveying I/O signals are LGA

• SMD

• LGA on the 4 external sides

*: The metallic shield used on LE51-868 S covers all the SMD components

3.2. Mechanical dimensions

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LE51-868 S RF Module User Guide

3.3. Recommended Land pattern

3.4. DC Characteristics

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Measured on DIP interface with T = 25°C, Vdd = 3V, 50Ω impedance and default power register setting if nothing else noted.

Max limits apply over the entire operating range, T=-40°C to +85°C, Vdd=2V to 3.6V and all channels.

Characteristics LE51-868 S Min. Typ. Max. Power Supply

(VDD): Consumption

Stand-by (32.768 kHz On) :

I/O low level : I/O high level :

Transmission:

Command/Data mode

Reception :

+2.0V +3.0V +3.6V

55mA@25mW 66mA@35mW 11mA 13mA TBD < 2uA

GND - 0.2x V

0.8x V

- V

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3.5. LE51-868 S Functional Characteristics

Measured on DIP interface with T = 25°C, Vdd = 3V, 50Ω impedance and default power register setting if nothing else noted.

Frequency Band 868.178 MHz – 868.222 MHz

RF Data Rate 100 bps Number of channels 1 Total slot number 480 Slot Width 100 Hz Blacklisted slots Center Frequency 868.2 MHz Total Bandwidth 48 kHz

Modulation Format (D)BPSK Technology Sigfox Protocol RF Output Power

0 to 19; 221 to 259; 460 to 480

Transmission

Up to 30mW @3.0 Volts

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Limits allowed by ETSI Standard are reported in the table below:

3.6. Digital Characteristic

Function Characteristics

• 128 kB + 8 kB in system programmable flash

µC

Serial link

• 8 kB RAM

• 2 kB E2PROM

• RS232 TTL Full Duplex

• 1200 to 115200 bps

• 7 or 8 bits

• Parity management

• Flow control

o Hardware (RTS/CTS)

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Embedded software functionality

• Flexibility:

o Pre flashed o Customization capability o Download over the air

3.7. Absolute Maximum Ratings

Voltage applied to Vcc, VDD :

Voltage applied to “TTL” Input :

-0.3V to +3.6V

-0.3V to VDD+0.3V

3.8. Ordering Information

The following equipments can be ordered:

• The SMD version (LE51-868 S)

• The DIP interface version (LE51-868 S)

• The Demo Case (LE51-868 S) composed by n.1 evaluation boards, n.1 DIP interface

boards, RF antennas, serial cable, battery.

The versions below are considered standard and should be readily available. For other versions, please contact Telit. Please make sure to give the complete part number when ordering.

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LE51

868 S

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Equipment

SMD Version

LE51-868 S/SMD

DIP Version

Demo Case

D LE51-868 S

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4. Technical Description

4.1. Module Top View (cover side)

CAUTION: reserved pins must not be connected

CAUTION: In case you want to use in the same application Telit ZE51 or ZE61 modules J9 and J8 should not be connected, since reserved on these modules (see foot notes on PinOut tables.

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4.2. Pin-out of the module LE51-868 S

Pin Pin name Pin type Signal level Function

J30 GND Gnd RF Ground connection for external antenna J29 Ext_Antenna RF RF I/O connection to external antenna J28 GND Gnd RF Ground connection for external antenna J27 GND Gnd Ground J26 GND Gnd Ground J25 VDD Power Digital and Radio part power supply pin J24 CTS I TTL Clear To Send J23 RESET I TTL µC reset ( Active low with internal pull-up ) J22 RTS O TTL Request To Send J21 RXD I TTL RxD UART – Serial Data Reception J20 GND Gnd Ground J19 TXD O TTL TxD UART – Serial Data Transmission J18 WAKEUP I TTL Wake-up (Active high with internal pull-down: when set to 1 the

J17 GND Gnd Ground J16 PROG I TTL Signal for serial µC flashing (Active high with internal pull-down) J15 GND Gnd Ground J14 PDI_DATA I/O TTL Program and Debug Interface DATA J13 GND Gnd Ground J12 GND Gnd Ground J11 GND Gnd Ground J10 PDI_CLK I TTL Program and Debug Interface CLOCK

IO91

IO8_A

J7 IO7_A I/O analog Analog Input N°7 (Logic I/O capability) J6 IO6_A I/O analog Analog Input N°6 (Logic I/O capability) J5 IO5_A I/O analog Analog Input N°5 (Logic I/O capability) J4 IO4_A I/O analog Analog Input N°4 (Logic I/O capability) J3 IO3_A I/O analog Analog Input N°3 (Logic I/O capability) J2 STANDBY

STATUS

J1 RADIO STATUS O TTL

I/O I/O

O TTL

TTL

analog

module is awakened)

Digital I/O N°9 with interrupt Analog Input I/O N°8 with interrupt (Logic I/O capability)

Signal indicating stand-by status

Signal indicating reception or transmission of radio frame

1, 2

In case you want to use in the same application Telit ZE51 or ZE61 modules J9 and J8 should not be connected, since

reserved on these modules.

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4.3. Pin-out of the DIP Interface

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4.4. Pin-out correspondence table

Pin-Out correspondence between LE51-868 S/DIP and LE51-868 S/SMD.

LE51-868 S/DIP LE51-868 S/SMD Comments

Connector Pin Name Pin Pin Name

1 2 GND 3 P1 J5 IO5_A 4 P2 J9 IO9_I Reserved Pin

RF connection

5 P3 J2 STANDBY STATUS 6 P4 J1 RADIO STATUS 7 P5 J4 IO4_A 8 P6 J3 IO3_A 9 GND 10 J25 VDD

11 J16 PROG 12 J22 RTS 13 J24 CTS 14 J23 RESET 15 J21 RxD 16 J19 TxD 17 J18 WAKEUP 18 J22 RTS 19 P7 J6 IO6_A 20 GND

1 J14 PDI_DATA 2 J10 PDI_CLK 3 J23 RESET 4 J25 VDD 5 GND

J7 IO7_A J8 IO8_AD_DA Reserved Pin

SMA connector

J29

Ext_Antenna (Unbalanced RF)

J4 Connector for debugging

A 50 Ohm coplanar wave guide and a matching network connect J29 to J3

and flashing

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4.5. Description of the signals

Signals Description

RESET

TXD, RXD

CTS

RTS

WAKEUP

RADIO STATUS

STANDBY STATUS

External hardware reset of the radio module. Active on low state.

Serial link signals, format NRZ/TTL: TXD is for outgoing data. RXD is for incoming data. The ‘1’ is represented by a high state.

Incoming signal. Indicates whether the module can send serial data to user (Active, on low state) or not (inactive, on high state).

Outgoing signal. Indicates whether the user can transmit serial data (active, on low state) or not (inactive, on high state).

I/O, configurable as input or as output.

Input signal which indicates to the module to wake up from low-power mode.

Output signal which indicates the status of the radio. Set to VCC during radio transmission or as soon as a radio frame is detected with correct synchronization word. The signals returns to GND at the end of transmission or as soon as the frame reception is finished.

The ‘STAND BY STATUS’ output signal is set to logical ‘1’ while the module is operating and return to ‘0’ during stand by periods.

5. Process Information

5.1. Delivery

LE51-868 S modules are delivered in plastic tray packaging, each tray including 50 units. The dimensions of the tray are the following: 329 mm x 176 mm x 5.6 mm. Each unit is placed in a 26.6 mm x 16 mm location. An empty tray weights 45 g and a loaded tray weights around 130 g.

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5.2. Storage

The optimal storage environment for LE51-868 S modules should be dust free, dry and the temperature should be included between -40°C and +85°C.

In case of a reflow soldering process, LE51-868 S radio modules must be submitted to a drying bake at +60°C during 24 hours. The drying bake must be used prior to the reflow soldering process in order to prevent a popcorn effect. After being submitted to the drying bake, LE modules must be soldered on host boards within 168 hours.

Also, it must be noted that due to some components, LE51-868 S modules are ESD sensitive device. Therefore, ESD handling precautions should be carefully observed.

5.3. Soldering pad pattern

The surface finished on the printed circuit board pads should be made of Nickel/Gold surface. The recommended soldering pad layout on the host board for the LE51-868 S is shown in the diagram below:

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All dimensions in mm

Neither via-holes nor wires are allowed on the PCB upper layer in area occupied by the module.

5.4. Solder past

LE51-868 S module is designed for surface mounting using half-moon solder joints (see diagram below). For proper module assembly, solder paste must be printed on the target surface of the host board. The solder paste should be eutectic and made of 95.5% of SN, 4% of Ag and 0.5% of Cu. The recommended solder paste height is 180 µm.

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The following diagram shows mounting characteristics for ME integration on host PCB:

5.5. Placement

The LE51-868 S module can be automatically placed on host boards by pick-and-place machines like any integrated circuit.

5.6. Soldering Profile (RoHS Process)

It must be noted that LE51-868 S module should not be allowed to be hanging upside down during the reflow operation. This means that the module has to be assembled on the side of the printed circuit board that is soldered last.

The recommendation for lead-free solder reflow in IPC/JEDEC J-STD-020D Standard should be followed.

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The barcode label located on the module shield is able to withstand the reflow temperature.

CAUTION - It must also be noted that if the host board is submitted to a wave soldering after the reflow operation, a solder mask must be used in order to protect the LE51-868 S radio module’s metal shield from being in contact with the solder wave.

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6. Board Mounting Recommendation

6.1. Electrical environment

The best performances of the LE51-868 S module are obtained in a “clean noise” environment. Some basic recommendations must be followed:

• Noisy electronic components (serial RS232, DC-DC Converter, Display, Ram, buses,

...) must be placed as far as possible from the LE51-868 S module.

• Switching components circuits (especially RS-232/TTL interface circuit power

supply) must be decoupled with a 100 µF tantalum capacitor. And the decoupling capacitor must be as close as possible to the noisy chip.

6.2. Power supply decoupling on LE51-868 S

module

The power supply of LE51-868 S module must be nearby decoupled. A LC filter must be placed as close as possible to the radio module power supply pin, VDD.

Power Supply

Symbols Reference Value Manufacturer

L1 LQH31MN1R0K03 1µH Murata

C1 GRM31CF51A226ZE01 22µF Murata

C2 Ceramic CMS 25V 100nF Multiple

C1 C2

Vdd

LE51-868 S RF Module User Guide

6.3. RF layout considerations

Basic recommendations must be followed to achieve a good RF layout:

• It is recommended to fill all unused PCB area around the module with ground plane

• The radio module ground pin must be connected to solid ground plane.

• If the ground plane is on the bottom side, a via (plated hole) must be used in front of

each ground pad. Especially J28 and J30 (RF Gnd) pins should be grounded by means of several holes to be located right next to the pins, thus minimizing inductance and preventing mismatch and losses.

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6.4. Antenna connections on printed circuit

boards

Special care must be taken when connecting an antenna or a connector to the module. The RF output impedance is 50Ω, so the strip between the pad and the antenna or connector must be 50Ω following the tables below. Ground lines should be connected to the ground plane with as many vias as possible, but not too close to the signal line.

PCB material PCB thickness H (mm) Coplanar line W (mm) Coplanar line G (mm)

0.8 1 0.3

FR4

1.6 1 0.2

Table 1 : Values for double face PCB with ground plane around and under coplanar wave guide (recommended)

PCB material PCB thickness H (mm) Coplanar line W (mm) Coplanar line G (mm)

0.8 1 0.22

FR4

1.6 1 0.23

Table 2 : Values for simple face PCB with ground plane around coplanar wave guide (not recommended)

6.5. LE51-868 S Interfacing

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LE51-868 S RF Module User Guide

7. Safety Recommendations

READ CAREFULLY

Be sure the use of this product is allowed in the country and in the environment required. The use of this product may be dangerous and has to be avoided in the following areas:

• Where it can interfere with other electronic devices in environments such as hospitals,

airports, aircrafts, etc.

• Where there is risk of explosion such as gasoline stations, oil refineries, etc. It is

responsibility of the user to enforce the country regulation and the specific

environment regulation. Do not disassemble the product; any mark of tampering will compromise the warranty validity. We recommend following the instructions of the hardware user guides for a correct wiring of the product. The product has to be supplied with a stabilized voltage source and the wiring has to be conforming to the security and fire prevention regulations. The product has to be handled with care, avoiding any contact with the pins because electrostatic discharges may damage the product itself. Same cautions have to be taken for the SIM, checking carefully the instruction for its use. Do not insert or remove the SIM when the product is in power saving mode. The system integrator is responsible of the functioning of the final product; therefore, care has to be taken to the external components of the module, as well as of any project or installation issue, because the risk of disturbing the GSM network or external devices or having impact on the security. Should there be any doubt, please refer to the technical documentation and the regulations in force. Every module has to be equipped with a proper antenna with specific characteristics. The antenna has to be installed with care in order to avoid any interference with other electronic devices and has to guarantee a minimum distance from the body (20 cm). In case of this requirement cannot be satisfied, the system integrator has to assess the final product against the SAR regulation.

The European Community provides some Directives for the electronic equipments introduced on the market. All the relevant information’s are available on the European Community website:

http://ec.europa.eu/enterprise/sectors/rtte/documents/

The text of the Directive 99/05 regarding telecommunication equipments is available, while the applicable Directives (Low Voltage and EMC) are available at:

http://ec.europa.eu/enterprise/sectors/electrical/

1VV0301131Rev.0 – 2014-01-16

8. Glossary

LE51-868 S RF Module User Guide

1VV0301131Rev.0 – 2014-01-16

ACP AFA bps BPSK BW dB dBm E2PROM e.r.p ETSI GFSK I ISM kB kbps kcps kHz LBT LGA MHz mW O PER ppm RAM RF RoHS RxD SMD SRD TxD UART µC

Adjacent Channel Power Adaptive Frequency Agility Bits per second Binary Phase Shift Keying Bandwidth Decibel Power level in decibel milliwatt (10 log (P/1mW)) Electrically Erasable Programmable Read Only Memory Effective radiated power European Telecommunication Standard Institute Gaussian Frequency Shift Keying Input Industrial, Scientific and Medical KiloByte Kilobits per second Kilochips per second Kilo Hertz Listen Before Talk Land Grid Array Mega Hertz milliwatt Output Packet Error Rate Parts per million Random Access Memory Radio Frequency Restriction of Hazardous Substances Receive Data Surface Mounted Device Short Range Device Transmit Data Universal Asynchronous Receiver Transmitter microcontroller

9. Document History

Revision Date Changes

0 2014/01/16 First release

LE51-868 S RF Module User Guide

1VV0301131Rev.0 – 2014-01-16

Telit Wireless Solutions LE51-868 S User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual