Ublox SARA-G3 Quick setup guide

SARA-G3 and SARA-U2 series
GSM/GPRS and GSM/EGPRS/HSPA
Cellular Modules
System Integration Manual
Abstract
This document describes the features and the system integration of
the SARA-G3 series GSM/GPRS cellular modules and the SARA-U2
GSM/EGPRS/HSPA cellular modules.
These modules are complete and cost efficient solutions offering
voice and/or data communication over diverse cellular radio access
technologies in the same compact SARA form factor: the SARA-G3
series support up to 4-band GSM/GPRS while the SARA-U2 series
support 2-band high-speed HSPA and up to 2-band GSM/EGPRS.
www.u-blox.com
UBX-13000995 - R08

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Document Information
Title
SARA-G3 and SARA-U2 series
Subtitle
GSM/GPRS and GSM/EGPRS/HSPA
Cellular Modules
Document type
System Integration Manual
Document number
UBX-13000995
Revision, date
R08
29-Apr-2014
Document status
Objective Specification
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
Firmware version
PCN / IN
SARA-G300
SARA-G300-00S-00
08.58
GSM.G2-TN-13007
SARA-G310
SARA-G310-00S-00
08.58
GSM.G2-TN-13007
SARA-G340
SARA-G340-00S-00
08.49
UBX-14000382
SARA-G350
SARA-G350-00S-00
08.49
GSM.G2-TN-13002
SARA-G350 ATEX
SARA-G350-00X-00
08.49
GSM.G2-TN-13002
SARA-U260
SARA-U260-00S-00
TBD
TBD
SARA-U270
SARA-U270-00S-00
TBD
TBD
SARA-U280
SARA-U280-00S-00
TBD
TBD
SARA-U290
SARA-U290-00S-00
TBD
TBD
SARA-U290-60S-00
TBD
TBD
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, please visit www.u-blox.com.
Copyright © 2014, u-blox AG
Trademark Notice
Microsoft and Windows are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries.
All other registered trademarks or trademarks mentioned in this document are property of their respective owners.

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Preface
u-blox Technical Documentation
As part of our commitment to customer support, u-blox maintains an extensive volume of technical
documentation for our products. In addition to our product-specific technical data sheets, the following manuals
are available to assist u-blox customers in product design and development.
AT Commands Manual: This document provides the description of the AT commands supported by the
u-blox cellular modules.
System Integration Manual: This document provides the description of u-blox cellular modules’ system
from the hardware and the software point of view, it provides hardware design guidelines for the optimal
integration of the cellular modules in the application device and it provides information on how to set up
production and final product tests on application devices integrating the cellular modules.
Application Notes: These documents provide guidelines and information on specific hardware and/or
software topics on u-blox cellular modules. See Related documents for a list of application notes related to
your cellular module.
How to use this Manual
The SARA-G3 and SARA-U2 series System Integration Manual provides the necessary information to successfully
design in and configure these u-blox cellular modules.
This manual has a modular structure. It is not necessary to read it from the beginning to the end.
The following symbols are used to highlight important information within the manual:
An index finger points out key information pertaining to module integration and performance.
A warning symbol indicates actions that could negatively impact or damage the module.
Questions
If you have any questions about u-blox cellular Integration:
Read this manual carefully.
Contact our information service on the homepage http://www.u-blox.com
Technical Support
Worldwide Web
Our website (www.u-blox.com) is a rich pool of information. Product information and technical documents can
be accessed 24h a day.
By E-mail
If you have technical problems or cannot find the required information in the provided documents, contact the
closest Technical Support office. To ensure that we process your request as soon as possible, use our service pool
email addresses rather than personal staff email addresses. Contact details are at the end of the document.
Helpful Information when Contacting Technical Support
When contacting Technical Support, have the following information ready:
Module type (e.g. SARA-G350) and firmware version
Module configuration
Clear description of your question or the problem
A short description of the application
Your complete contact details

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Contents
Preface ................................................................................................................................3
Contents..............................................................................................................................4
1System description.......................................................................................................8
1.1 Overview .............................................................................................................................................. 8
1.2 Architecture........................................................................................................................................ 10
1.2.1 Internal blocks ............................................................................................................................. 12
1.3 Pin-out ............................................................................................................................................... 13
1.4 Operating modes................................................................................................................................ 18
1.5 Supply interfaces ................................................................................................................................ 20
1.5.1 Module supply input (VCC) ......................................................................................................... 20
1.5.2 RTC supply input/output (V_BCKP) .............................................................................................. 29
1.5.3 Generic digital interfaces supply output (V_INT)........................................................................... 30
1.6 System function interfaces.................................................................................................................. 31
1.6.1 Module power-on ....................................................................................................................... 31
1.6.2 Module power-off ....................................................................................................................... 34
1.6.3 Module reset ............................................................................................................................... 36
1.6.4 External 32 kHz signal input (EXT32K) ......................................................................................... 37
1.6.5 Internal 32 kHz signal output (32K_OUT) .................................................................................... 37
1.7 Antenna interface............................................................................................................................... 38
1.7.1 Antenna RF interface (ANT) ......................................................................................................... 38
1.7.2 Antenna detection interface (ANT_DET) ...................................................................................... 39
1.8 SIM interface ...................................................................................................................................... 39
1.8.1 (U)SIM card interface................................................................................................................... 39
1.8.2SIM card detection interface (SIM_DET) ....................................................................................... 39
1.9 Serial interfaces .................................................................................................................................. 40
1.9.1 Asynchronous serial interface (UART)........................................................................................... 40
1.9.2 Auxiliary asynchronous serial interface (UART AUX) ..................................................................... 53
1.9.3 USB interface............................................................................................................................... 53
1.9.4 DDC (I2C) interface ...................................................................................................................... 55
1.10 Audio interface ............................................................................................................................... 57
1.10.1 Analog audio interface ................................................................................................................ 57
1.10.2 Digital audio interface ................................................................................................................. 59
1.10.3 Voice-band processing system ..................................................................................................... 61
1.11 General Purpose Input/Output (GPIO) ............................................................................................. 64
1.12 Reserved pins (RSVD) ...................................................................................................................... 68
1.13 System features............................................................................................................................... 69
1.13.1 Network indication ...................................................................................................................... 69
1.13.2 Antenna detection ...................................................................................................................... 69
1.13.3 Jamming detection ...................................................................................................................... 69

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1.13.4 TCP/IP and UDP/IP ....................................................................................................................... 70
1.13.5 FTP .............................................................................................................................................. 70
1.13.6 HTTP ........................................................................................................................................... 70
1.13.7 SMTP........................................................................................................................................... 70
1.13.8 SSL .............................................................................................................................................. 71
1.13.9 Dual stack IPv4/IPv6 ..................................................................................................................... 71
1.13.10 Smart temperature management ............................................................................................. 72
1.13.11 AssistNow clients and GNSS integration................................................................................... 74
1.13.12 Hybrid positioning and CellLocateTM ......................................................................................... 75
1.13.13 Firmware upgrade Over AT (FOAT) .......................................................................................... 77
1.13.14 Firmware upgrade Over The Air (FOTA).................................................................................... 77
1.13.15 In-Band modem (eCall / ERA-GLONASS) .................................................................................. 78
1.13.16 SIM Access Profile (SAP)........................................................................................................... 78
1.13.17 Power saving ........................................................................................................................... 80
2Design-in.....................................................................................................................81
2.1 Overview ............................................................................................................................................ 81
2.2 Supply interfaces ................................................................................................................................ 82
2.2.1 Module supply (VCC) .................................................................................................................. 82
2.2.2 RTC supply (V_BCKP)................................................................................................................... 93
2.2.3 Interface supply (V_INT)............................................................................................................... 95
2.3 System functions interfaces ................................................................................................................ 96
2.3.1 Module power-on (PWR_ON) ...................................................................................................... 96
2.3.2 Module reset (RESET_N) .............................................................................................................. 97
2.3.3 32 kHz signal (EXT32K and 32K_OUT)......................................................................................... 98
2.4 Antenna interface............................................................................................................................. 100
2.4.1 Antenna RF interface (ANT) ....................................................................................................... 100
2.4.2 Antenna detection interface (ANT_DET) .................................................................................... 105
2.5 SIM interface .................................................................................................................................... 108
2.6 Serial interfaces ................................................................................................................................ 114
2.6.1 Asynchronous serial interface (UART)......................................................................................... 114
2.6.2 Auxiliary asynchronous serial interface (UART AUX) ................................................................... 119
2.6.3 Universal Serial Bus (USB) .......................................................................................................... 121
2.6.4 DDC (I2C) interface .................................................................................................................... 123
2.7 Audio interface................................................................................................................................. 129
2.7.1 Analog audio interface .............................................................................................................. 129
2.7.2 Digital audio interface ............................................................................................................... 135
2.8 General Purpose Input/Output (GPIO) ............................................................................................... 138
2.9 Reserved pins (RSVD) ........................................................................................................................ 139
2.10 Module placement ........................................................................................................................ 139
2.11 Module footprint and paste mask ................................................................................................. 140
2.12 Thermal guidelines ........................................................................................................................ 141
2.13 ESD guidelines .............................................................................................................................. 143
2.13.1 ESD immunity test overview ...................................................................................................... 143

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2.13.2 ESD immunity test of u-blox SARA-G3 and SARA-U2 reference designs..................................... 143
2.13.3 ESD application circuits.............................................................................................................. 144
2.14 SARA-G350 ATEX integration in explosive atmospheres applications ............................................ 146
2.14.1 General guidelines..................................................................................................................... 146
2.14.2 Guidelines for VCC supply circuit design ................................................................................... 147
2.14.3 Guidelines for antenna RF interface design................................................................................ 148
2.15 Schematic for SARA-G3 and SARA-U2 series module integration .................................................. 149
2.15.1 Schematic for SARA-G300 / SARA-G310 modules integration ................................................... 149
2.15.2 Schematic for SARA-G340 / SARA-G350 modules integration ................................................... 150
2.15.3 Schematic for SARA-U2 series modules integration ................................................................... 151
2.16 Design-in checklist ........................................................................................................................ 152
2.16.1 Schematic checklist ................................................................................................................... 152
2.16.2 Layout checklist ......................................................................................................................... 153
2.16.3 Antenna checklist ...................................................................................................................... 153
3Handling and soldering ...........................................................................................154
3.1 Packaging, shipping, storage and moisture preconditioning ............................................................. 154
3.2 Handling........................................................................................................................................... 154
3.3 Soldering .......................................................................................................................................... 155
3.3.1 Soldering paste.......................................................................................................................... 155
3.3.2 Reflow soldering ....................................................................................................................... 155
3.3.3 Optical inspection...................................................................................................................... 156
3.3.4 Cleaning.................................................................................................................................... 156
3.3.5 Repeated reflow soldering......................................................................................................... 157
3.3.6 Wave soldering.......................................................................................................................... 157
3.3.7 Hand soldering .......................................................................................................................... 157
3.3.8 Rework...................................................................................................................................... 157
3.3.9 Conformal coating .................................................................................................................... 157
3.3.10 Casting...................................................................................................................................... 157
3.3.11 Grounding metal covers ............................................................................................................ 157
3.3.12 Use of ultrasonic processes........................................................................................................ 157
4Approvals..................................................................................................................158
4.1 Product certification approval overview............................................................................................. 158
4.2 Federal Communications Commission and Industry Canada notice ................................................... 159
4.2.1 Safety warnings review the structure ......................................................................................... 159
4.2.2 Declaration of conformity –United States only .......................................................................... 159
4.2.3 Modifications ............................................................................................................................ 160
4.3 R&TTED and European conformance CE mark .................................................................................. 161
4.4 Anatel certification ........................................................................................................................... 162
4.5 SARA-G350 ATEX conformance for use in explosive atmospheres .................................................... 163
5Product testing .........................................................................................................164
5.1 u-blox in-series production test......................................................................................................... 164
5.2 Test parameters for OEM manufacturer ............................................................................................ 164

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5.2.1 “Go/No go” tests for integrated devices.................................................................................... 165
5.2.2 Functional tests providing RF operation ..................................................................................... 165
Appendix ........................................................................................................................168
AMigration between LISA and SARA-G3 modules ...................................................168
A.1 Overview .......................................................................................................................................... 168
A.2 Checklist for migration ..................................................................................................................... 169
A.3 Software migration........................................................................................................................... 170
A.4 Hardware migration.......................................................................................................................... 170
A.4.1 Supply interfaces ....................................................................................................................... 170
A.4.2 System functions interfaces ....................................................................................................... 171
A.4.3 Antenna interface ..................................................................................................................... 172
A.4.4 SIM interface ............................................................................................................................. 173
A.4.5 Serial interfaces ......................................................................................................................... 173
A.4.6 Audio interfaces ........................................................................................................................ 174
A.4.7 GPIO pins .................................................................................................................................. 174
A.4.8 Reserved pins ............................................................................................................................ 174
A.4.9 Pin-out comparison between LISA and SARA-G3....................................................................... 175
BMigration between SARA-G3 and SARA-U2...........................................................180
B.1 Overview .......................................................................................................................................... 180
B.2 Pin-out comparison between SARA-G3 and SARA-U2 ...................................................................... 181
B.3 Schematic for SARA-G3 and SARA-U2 integration............................................................................ 183
CGlossary ....................................................................................................................184
Related documents.........................................................................................................186
Revision history..............................................................................................................187
Contact............................................................................................................................188

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1System description
1.1 Overview
SARA-G3 series GSM/GPRS cellular modules and SARA-U2 series GSM/EGPRS/HSPA cellular modules are versatile
solutions offering voice and/or data communication over diverse radio access technologies in the same miniature
SARA LGA form factor (26 x 16 mm) that allows seamless drop-in migration between the two SARA-G3 and
SARA-U2 series and easy migration to u-blox LISA-U series GSM/EGPRS/HSPA+ modules, LISA-C2 series CDMA
modules, TOBY-L1 series LTE modules and to TOBY-L2 series GSM/EGPRS/DC-HSPA+/LTE modules.
SARA-G350 and SARA-G340 are respectively quad-band and dual-band full feature GSM/GPRS cellular modules
with a comprehensive feature set including an extensive set of internet protocols and access to u-blox GNSS
positioning chips and modules, with embedded A-GPS (AssistNow Online and AssistNow Offline) functionality.
SARA-G310 and SARA-G300 are respectively quad-band and dual-band GSM/GPRS cellular modules targeted for
high volume cost sensitive applications, providing GSM/GPRS functionalities with a reduced set of additional
features to minimize the customer’s total cost of ownership.
SARA-U2 series include variants supporting band combination for North America and band combination for
Europe, Asia and other countries. For each combination, a complete UMTS/GSM variant and a cost-saving
UMTS-only variant are available. All SARA-U2 series modules provide a rich feature set including an extensive set
of internet protocols, dual-stack IPv4 / IPv6 and access to u-blox GNSS positioning chips and modules, with
embedded A-GPS (AssistNow Online and AssistNow Offline) functionality.
Table 1 describes a summary of interfaces and features provided by SARA-G3 and SARA-U2 series modules.
Module
Data rate
Bands
Interfaces
Audio
Functions
3G Up-Link [Mb/s]
3G Down-Link [Mb/s]
2G Up-Link [kb/s]
2G Down-Link [kb/s]
3G bands [MHz]
2G bands [MHz]
UART
SPI
USB
DDC (I2C)
GPIO
Analog audio
Digital audio over USB
Digital audio over I2S
Network indication
Antenna supervisor
Jamming detection
Embedded TCP / UDP
Embedded HTTP, FTP
Embedded SSL / TLS
GNSS via Modem
AssistNow Software
CellLocate
FW update via serial
eCall / ERA-GLONASS
Low power idle-mode
ATEX certification
Dual stack IPv4/IPv6
SARA-G300
42.8
85.6
900/1800
2
•
E
SARA-G310
42.8
85.6
4-band
2
•
E
SARA-G340
42.8
85.6
900/1800
2
1
4
1
1
•
•
•
•
•
•
•
•
•
•
•
SARA-G350
42.8
85.6
4-band
2
1
4
1
1
•
•
•
•
•
•
•
•
•
•
•
SARA-G350 ATEX
42.8
85.6
4-band
2
1
4
1
1
•
•
•
•
•
•
•
•
•
•
•
•
SARA-U260
5.76
7.2
85.6
236.8
850/1900
850/1900
1
1
1
9
F
1
•
•
•
•
•
•
•
•
•
•
•
•
SARA-U270
5.76
7.2
85.6
236.8
900/2100
900/1800
1
1
1
9
F
1
•
•
•
•
•
•
•
•
•
•
•
•
•
SARA-U280
5.76
7.2
850/1900
1
1
1
9
F
1
•
•
•
•
•
•
•
•
•
•
•
•
SARA-U290
5.76
7.2
900/2100
1
1
1
9
F
1
•
•
•
•
•
•
•
•
•
•
•
•
•
E = 32 kHz signal at EXT32K input pin is required for low power idle-mode
F = not supported by initial FW release
Table 1: SARA-G3 series
1
and SARA-U2 series
2
features summary
1
SARA-G350 ATEX modules provide the same feature set of the SARA-G350 modules plus the certification for use in potentially explosive
atmospheres. Unless otherwise specified, SARA-G350 refers to all SARA-G350 ATEX modules and SARA-G350 modules.
2
SARA-U290 modules include ‘00’ and ‘60’ FW versions: SARA-U290-60S is approved and locked for SoftBank Japanese network operator.

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Table 2 reports a summary of 2G cellular characteristics of SARA-G3 and SARA-U2 series modules.
Item
SARA-U260
SARA-U270
SARA-G300 / SARA-G340
SARA-G310 / SARA-G350
Protocol stack
3GPP Release 7
3GPP Release 7
3GPP Release 99
3GPP Release 99
MS class
Class B3
Class B3
Class B3
Class B3
Bands4
GSM 850 MHz
PCS 1900 MHz
E-GSM 900 MHz
DCS 1800 MHz
E-GSM 900 MHz
DCS 1800 MHz
GSM 850 MHz
E-GSM 900 MHz
DCS 1800 MHz
PCS 1900 MHz
Power class
Class 4 (33 dBm)
for 850 band
Class 1 (30 dBm)
for 1900 band
Class 4 (33 dBm)
for 900 band
Class 1 (30 dBm)
for 1800 band
Class 4 (33 dBm)
for 900 band
Class 1 (30 dBm)
for 1800 band
Class 4 (33 dBm)
for 850/900 bands
Class 1 (30 dBm)
for 1800/1900 bands
PS data rate5
GPRS multi-slot class 126
CS 1-4, 85.6 kb/s DL
CS 1-4, 85.6 kb/s UL
EDGE multi-slot class 126
MCS 1-9, 236.8 kb/s DL
MCS 1-4, 70.4 kb/s UL
GPRS multi-slot class 126
CS 1-4, 85.6 kb/s DL
CS 1-4, 85.6 kb/s UL
EDGE multi-slot class 126
MCS 1-9, 236.8 kb/s DL
MCS 1-4, 70.4 kb/s UL
GPRS multi-slot class 107
CS 1-4, 85.6 kb/s DL
CS 1-4, 42.8 kb/s UL5
GPRS multi-slot class 107
CS 1-4, 85.6 kb/s DL
CS 1-4, 42.8 kb/s UL
CS data rate5
Up to 9.6 kb/s DL/UL
Transparent mode
Non transparent mode
Up to 9.6 kb/s DL/UL
Transparent mode
Non transparent mode
Up to 9.6 kb/s DL/UL
Transparent mode
Non transparent mode
Up to 9.6 kb/s DL/UL
Transparent mode
Non transparent mode
Table 2: SARA-G3 series and SARA-U2 series 2G characteristics summary
Table 3 reports a summary of 3G cellular characteristics of SARA-U2 series modules.
Item
SARA-U260
SARA-U270
SARA-U280
SARA-U290
Protocol stack
3GPP Release 7
3GPP Release 7
3GPP Release 7
3GPP Release 7
UE class
Class A8
Class A8
Class A8
Class A8
Bands
Band V (850 MHz)
Band II (1900 MHz)
Band VIII (900 MHz)
Band I (2100 MHz)
Band V (850 MHz)
Band II (1900 MHz)
Band VIII (900 MHz)
Band I (2100 MHz)
Power class
Class 3 (24 dBm)
for all bands
Class 3 (24 dBm)
for all bands
Class 3 (24 dBm)
for all bands
Class 3 (24 dBm)
for all bands
PS data rate5
HSUPA category 6
5.76 Mb/s UL
HSDPA category 8
7.2 Mb/s DL
HSUPA category 6
5.76 Mb/s UL
HSDPA category 8
7.2 Mb/s DL
HSUPA category 6
5.76 Mb/s UL
HSDPA category 8
7.2 Mb/s DL
HSUPA category 6
5.76 Mb/s UL
HSDPA category 8
7.2 Mb/s DL
CS data rate5
Up to 64 kb/s DL/UL
Up to 64 kb/s DL/UL
Up to 64 kb/s DL/UL
Up to 64 kb/s DL/UL
Table 3: SARA-U2 series 3G characteristics summary
3
Device can be attached to both GPRS and GSM services (i.e. Packet Switch and Circuit Switch mode) using one service at a time.
4
The 2G 850 / 1900 MHz and 3G 850 / 1900 MHz bands are mainly operative in America. The 2G 900 / 1800 MHz and 3G 900 / 2100 MHz
bands are mainly operative in Europe, Asia and other countries.
5
The maximum bit rate of the module depends on the actual network environmental conditions and settings.
6
GPRS/EDGE multi-slot class 12 implies a maximum of 4 slots in DL (reception) and 4 slots in UL (transmission) with 5 slots in total.
7
GPRS multi-slot class 10 implies a maximum of 4 slots in DL (reception) and 2 slots in UL (transmission) with 5 slots in total.
8
Device can work simultaneously in Packet Switch and Circuit Switch mode: voice calls are possible while the data connection is active
without any interruption in service.

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1.2 Architecture
Figure 1 summarizes the architecture of SARA-G300 and SARA-G310 modules, while Figure 2 summarizes the
architecture of SARA-G340 and SARA-G350 modules, describing the internal blocks of the modules, consisting
of the RF, Baseband and Power Management main sections, and the available interfaces.
Memory
V_BCKP (RTC)
V_INT (I/O)
32 kHz
26 MHz
RF
Transceiver
Power
Management
ANT SAW
Filter
Switch
VCC (Supply)
32 kHz
Auxiliary UART
SIM
UART
Power-On
Reset
Cellular
BaseBand
Processor
PA
Figure 1: SARA-G300 and SARA-G310 modules block diagram
Memory
V_BCKP (RTC)
V_INT (I/O)
26 MHz 32.768 kHz
RF
Transceiver
Power
Management
Cellular
BaseBand
Processor
ANT SAW
Filter
Switch
PA
VCC (Supply)
Auxiliary UART
DDC (for GNSS)
SIM Card Detection
SIM
UART
Power-On
Reset
Digital Audio
Analog Audio
GPIO
Antenna Detection
Figure 2: SARA-G340 and SARA-G350 modules block diagram

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Figure 3 summarizes the architecture of SARA-U260 and SARA-U270 modules, while Figure 4 summarizes the
architecture of SARA-U280 and SARA-U290 modules, describing the internal blocks of the modules, consisting
of the RF, Baseband and Power Management main sections, and the available interfaces.
Memory
V_BCKP (RTC)
V_INT (I/O)
RF
Transceiver
Power
Management
Cellular
BaseBand
Processor
ANT
VCC (Supply)
USB
DDC (I2C)
SIM card detection
SIM
UART
Power-On
Reset
Digital audio (I2S)
GPIO
Antenna detection
3G PA
26 MHz
Duplexer
Filter
Switch
2G PA
LNA
32.768 kHz
Figure 3: SARA-U260 and SARA-U270 modules block diagram
Memory
V_BCKP (RTC)
V_INT (I/O)
RF
Transceiver
Power
Management
Cellular
BaseBand
Processor
ANT
VCC (Supply)
USB
DDC (I2C)
SIM card detection
SIM
UART
Power-On
Reset
Digital audio (I2S)
GPIO
Antenna detection
3G PA
26 MHz
Duplexer
Filter
Switch
LNA
32.768 kHz
Figure 4: SARA-U280 and SARA-U290 modules block diagram

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1.2.1 Internal blocks
SARA-G3 and SARA-U2 series modules internally consist of the RF, Baseband and Power Management sections
here described with more details than the simplified block diagrams of Figure 1, Figure 2, Figure 3 and Figure 4.
RF section
The RF section is composed of the following main elements:
2G / 3G RF transceiver performing modulation, up-conversion of the baseband I/Q signals, down-conversion
and demodulation of the RF received signals. The RF transceiver includes:
Constant gain direct conversion receiver with integrated LNAs
Highly linear RF quadrature GMSK demodulator
Digital Sigma-Delta transmitter GMSK modulator
Fractional-N Sigma-Delta RF synthesizer
3.8 GHz VCO
Digital controlled crystal oscillator
2G / 3G Power Amplifier, which amplifies the signals modulated by the RF transceiver
RF switch, which connects the antenna input/output pin (ANT) of the module to the suitable RX/TX path
RX diplexer SAW (band pass) filters
26 MHz crystal, connected to the digital controlled crystal oscillator to perform the clock reference in
active-mode or connected-mode
Baseband and Power Management section
The Baseband and Power Management section is composed of the following main elements:
Baseband processor, a mixed signal ASIC which integrates:
Microprocessor for controller functions
DSP core for 2G / 3G Layer 1 and audio processing
Dedicated peripheral blocks for parallel control of the digital interfaces
Audio analog front-end
Memory system in a multi-chip package integrating two devices:
NOR flash non-volatile memory
RAM volatile memory
Voltage regulators to derive all the system supply voltages from the module supply VCC
Circuit for the RTC clock reference in low power idle-mode:
SARA-G340, SARA-G350 and SARA-U2 series modules are equipped with an internal 32.768 kHz crystal
connected to the oscillator of the RTC (Real Time Clock) block that gives the RTC clock reference needed
to provide the RTC functions as well as to reach the very low power idle-mode (with power saving
configuration enabled by the AT+UPSV command).
SARA-G300 and SARA-G310 modules are not equipped with an internal 32.768 kHz crystal: a proper
32 kHz signal must be provided at the EXT32K input pin of the modules to give the RTC clock reference
and to provide the RTC functions as well as to reach the very low power idle-mode (with power saving
configuration enabled by AT+UPSV). The 32K_OUT output pin of SARA-G300 and SARA-G310 provides
a 32 kHz reference signal suitable only to feed the EXT32K input pin, furnishes the reference clock for
the RTC, and allows low power idle-mode and RTC functions support with modules switched on.

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1.3 Pin-out
Table 4 lists the pin-out of the SARA-G3 and SARA-U2 series modules, with pins grouped by function.
Function
Pin Name
Module
Pin No
I/O
Description
Remarks
Power
VCC
All
51, 52, 53
I
Module supply
input
VCC pins are internally connected each other.
VCC supply circuit affects the RF performance and
compliance of the device integrating the module
with applicable required certification schemes.
See section 1.5.1 for functional description and
requirements for the VCC module supply.
See section 2.2.1 for external circuit design-in.
GND
All
1, 3, 5, 14,
20-22, 30,
32, 43, 50,
54, 55,
57-61,
63-96
N/A
Ground
GND pins are internally connected each other.
External ground connection affects the RF and
thermal performance of the device.
See section 1.5.1 for functional description.
See section 2.2.1 for external circuit design-in.
V_BCKP
All
2
I/O
Real Time Clock
supply
input/output
V_BCKP = 2.3 V (typical) on SARA-G3 series.
V_BCKP = 1.8 V (typical) on SARA-U2 series.
V_BCKP is generated by internal low power linear
regulator when valid VCC supply is present.
See section 1.5.2 for functional description.
See section 2.2.2 for external circuit design-in.
V_INT
All
4
O
Generic Digital
Interfaces supply
output
V_INT = 1.8 V (typical), generated by internal DC/DC
regulator when the module is switched on.
See section 1.5.3 for functional description.
See section 2.2.3 for external circuit design-in.
System
PWR_ON
All
15
I
Power-on input
High input impedance: input voltage level has to be
properly fixed, e.g. adding external pull-up.
See section 1.6.1 for functional description.
See section 2.3.1 for external circuit design-in.
RESET_N
All
18
I
External reset
input
A series Schottky diode is integrated in the module
as protection, and then an internal 10 kpull-up
resistor to V_INT is provided.
See section 1.6.3 for functional description.
See section 2.3.2 for external circuit design-in.
EXT32K
SARA-G300
SARA-G310
31
I
32 kHz input
Input for RTC reference clock, needed to enter the
low power idle-mode and provide RTC functions.
See section 1.6.4 for functional description.
See section 2.3.3 for external circuit design-in.
32K_OUT
SARA-G300
SARA-G310
24
O
32 kHz output
32 kHz output suitable only to feed the EXT32K
input giving the RTC reference clock, allowing low
power idle-mode and RTC functions support.
See section 1.6.5 for functional description.
See section 2.3.3 for external circuit design-in.
Antenna
ANT
All
56
I/O
RF input/output
for antenna
50 nominal characteristic impedance.
Antenna circuit affects the RF performance and
compliance of the device integrating the module
with applicable required certification schemes.
See section 1.7 for functional description and
requirements for the antenna RF interface.
See section 2.4 for external circuit design-in.
ANT_DET
SARA-G340
SARA-G350
SARA-U2
62
I
Input for antenna
detection
ADC input for antenna detection function.
See section 1.7.2 for functional description.
See section 2.4.2 for external circuit design-in.

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Function
Pin Name
Module
Pin No
I/O
Description
Remarks
SIM
VSIM
All
41
O
SIM supply output
VSIM = 1.80 V typ. or 2.85 V typ. automatically
generated according to the connected SIM type.
See section 1.8 for functional description.
See section 2.5 for external circuit design-in.
SIM_IO
All
39
I/O
SIM data
Data input/output for 1.8 V / 3 V SIM
Internal 4.7 kpull-up to VSIM.
See section 1.8 for functional description.
See section 2.5 for external circuit design-in.
SIM_CLK
All
38
O
SIM clock
3.25 MHz clock output for 1.8 V / 3 V SIM
See section 1.8 for functional description.
See section 2.5 for external circuit design-in.
SIM_RST
All
40
O
SIM reset
Reset output for 1.8 V / 3 V SIM
See section 1.8 for functional description.
See section 2.5 for external circuit design-in.
SIM_DET
All
42
I /
I/O
SIM detection /
GPIO
1.8 V input for SIM presence detection function.
Pin configurable also as GPIO on SARA-U2 series.
See section 1.8.2 for functional description.
See section 2.5 for external circuit design-in.
UART
RXD
All
13
O
UART data output
1.8 V output, Circuit 104 (RXD) in ITU-T V.24,
for AT, data, FOAT on SARA-G3 series modules,
for AT, data, FOAT, FW upgrade via EasyFlash tool
and diagnostic on SARA-U2 series modules.
See section 1.9.1 for functional description.
See section 2.6.1 for external circuit design-in.
TXD
All
12
I
UART data input
1.8 V input, Circuit 103 (TXD) in ITU-T V.24,
for AT, data, FOAT on SARA-G3 series modules,
for AT, data, FOAT, FW upgrade via EasyFlash tool
and diagnostic on SARA-U2 series modules.
Internal active pull-up to V_INT.
See section 1.9.1 for functional description.
See section 2.6.1 for external circuit design-in.
CTS
All
11
O
UART clear to
send output
1.8 V output, Circuit 106 (CTS) in ITU-T V.24.
See section 1.9.1 for functional description.
See section 2.6.1 for external circuit design-in.
RTS
All
10
I
UART ready to
send input
1.8 V input, Circuit 105 (RTS) in ITU-T V.24.
Internal active pull-up to V_INT.
See section 1.9.1 for functional description.
See section 2.6.1 for external circuit design-in.
DSR
All
6
O
UART data set
ready output
1.8 V output, Circuit 107 (DSR) in ITU-T V.24.
See section 1.9.1 for functional description.
See section 2.6.1 for external circuit design-in.
RI
All
7
O
UART ring
indicator output
1.8 V output, Circuit 125 (RI) in ITU-T V.24.
See section 1.9.1 for functional description.
See section 2.6.1 for external circuit design-in.
DTR
All
9
I
UART data
terminal ready
input
1.8 V input, Circuit 108/2 (DTR) in ITU-T V.24.
Internal active pull-up to V_INT.
See section 1.9.1 for functional description.
See section 2.6.1 for external circuit design-in.
DCD
All
8
O
UART data carrier
detect output
1.8 V input, Circuit 109 (DCD) in ITU-T V.24.
See section 1.9.1 for functional description.
See section 2.6.1 for external circuit design-in.

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Function
Pin Name
Module
Pin No
I/O
Description
Remarks
Auxiliary
UART
RXD_AUX
SARA-G3
28
O
Auxiliary UART
data output
1.8 V output, Circuit 104 (RXD) in ITU-T V.24,
for FW upgrade via EasyFlash tool and diagnostic.
Access by external test-point is recommended.
See section 1.9.2 for functional description.
See section 2.6.2 for external circuit design-in.
TXD_AUX
SARA-G3
29
I
Auxiliary UART
data input
1.8 V input, Circuit 103 (TXD) in ITU-T V.24,
for FW upgrade via EasyFlash tool and diagnostic.
Access by external test-point is recommended.
Internal active pull-up to V_INT.
See section 1.9.2 for functional description.
See section 2.6.2 for external circuit design-in.
USB
VUSB_DET
SARA-U2
17
I
USB detect input
High-Speed USB 2.0 interface input for VBUS (5 V
typical) USB supply sense. USB available for AT, data,
FOAT, FW upgrade via EasyFlash tool and diagnostic.
See section 1.9.3 for functional description.
See section 2.6.3 for external circuit design-in.
USB_D-
SARA-U2
28
I/O
USB Data Line D-
High-Speed USB 2.0 interface data line for AT, data,
FOAT, FW upgrade via EasyFlash tool and diagnostic.
90 nominal differential impedance.
Pull-up, pull-down and series resistors as required by
USB 2.0 specifications [14] are part of the USB pin
driver and need not be provided externally.
See section 1.9.3 for functional description.
See section 2.6.3 for external circuit design-in.
USB_D+
SARA-U2
29
I/O
USB Data Line D+
High-Speed USB 2.0 interface data line for AT, data,
FOAT, FW upgrade via EasyFlash tool and diagnostic.
90 nominal differential impedance.
Pull-up, pull-down and series resistors as required by
USB 2.0 specifications [14] are part of the USB pin
driver and need not be provided externally.
See section 1.9.3 for functional description.
See section 2.6.3 for external circuit design-in.
DDC
SCL
SARA-G340
SARA-G350
SARA-U2
27
O
I2C bus clock line
1.8 V open drain, for the communication with the
u-blox positioning modules / chips. Communication
with other external I2C-slave devices as an audio
codec is additionally supported by SARA-U2 series.
External pull-up required.
See section 1.9.4 for functional description.
See section 2.6.4 for external circuit design-in.
SDA
SARA-G340
SARA-G350
SARA-U2
26
I/O
I2C bus data line
1.8 V open drain, for the communication with
u-blox positioning modules / chips. Communication
with other external I2C-slave devices as an audio
codec is additionally supported by SARA-U2 series.
External pull-up required.
See section 1.9.4 for functional description.
See section 2.6.4 for external circuit design-in.

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Function
Pin Name
Module
Pin No
I/O
Description
Remarks
Analog
Audio
MIC_BIAS
SARA-G340
SARA-G350
46
O
Microphone
supply output
Supply output (2.2 V typ) for external microphone.
See section 1.10.1 for functional description.
See section 2.7.1 for external circuit design-in.
MIC_GND
SARA-G340
SARA-G350
47
I
Microphone
analog reference
Local ground for the external microphone (reference
for the analog audio uplink path).
See section 1.10.1 for functional description.
See section 2.7.1 for external circuit design-in.
MIC_N
SARA-G340
SARA-G350
48
I
Differential
analog audio
input (negative)
Differential analog audio signal input (negative)
shared for all the analog uplink path modes:
handset, headset, hands-free mode.
No internal DC blocking capacitor.
See section 1.10.1 for functional description.
See section 2.7.1 for external circuit design-in.
MIC_P
SARA-G340
SARA-G350
49
I
Differential
analog audio
input (positive)
Differential analog audio signal input (positive)
shared for all the analog uplink path modes:
handset, headset, hands-free mode.
No internal DC blocking capacitor.
See section 1.10.1 for functional description.
See section 2.7.1 for external circuit design-in.
SPK_P
SARA-G340
SARA-G350
44
O
Differential
analog audio
output (positive)
Differential analog audio signal output (positive)
shared for all the analog downlink path modes:
earpiece, headset and loudspeaker mode.
See section 1.10.1 for functional description.
See section 2.7.1 for external circuit design-in.
SPK_N
SARA-G340
SARA-G350
45
O
Differential
analog audio
output (negative)
Differential analog audio signal output (negative)
shared for all the analog downlink path modes:
earpiece, headset and loudspeaker mode.
See section 1.10.1 for functional description.
See section 2.7.1 for external circuit design-in.
Digital
Audio
I2S_CLK
SARA-G340
SARA-G350
SARA-U2
36
O /
I/O
I2S clock /
GPIO
1.8 V serial clock for PCM / normal I2S modes.
Pin configurable also as GPIO on SARA-U2 series.
See section 1.10.2 for functional description.
See section 2.7.2 for external circuit design-in.
I2S_RXD
SARA-G340
SARA-G350
SARA-U2
37
I /
I/O
I2S receive data /
GPIO
1.8 V data input for PCM / normal I2S modes.
Pin configurable also as GPIO on SARA-U2 series.
Internal active pull-down to GND.
See section 1.10.2 for functional description.
See section 2.7.2 for external circuit design-in.
I2S_TXD
SARA-G340
SARA-G350
SARA-U2
35
O /
I/O
I2S transmit data /
GPIO
1.8 V data output for PCM / normal I2S modes.
Pin configurable also as GPIO on SARA-U2 series.
See section 1.10.2 for functional description.
See section 2.7.2 for external circuit design-in.
I2S_WA
SARA-G340
SARA-G350
SARA-U2
34
O /
I/O
I2S word alignment /
GPIO
1.8 V word alignment for PCM / normal I2S modes
Pin configurable also as GPIO on SARA-U2 series.
See section 1.10.2 for functional description.
See section 2.7.2 for external circuit design-in.
CODEC_CLK
SARA-U2
19
O
Clock output
1.8 V master clock output for external audio codec
See section 1.10.2 for functional description.
See section 2.7.2 for external circuit design-in

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Function
Pin Name
Module
Pin No
I/O
Description
Remarks
GPIO
GPIO1
SARA-G340
SARA-G350
SARA-U2
16
I/O
GPIO
1.8 V GPIO by default configured as pin disabled.
See section 1.11 for functional description.
See section 2.8 for external circuit design-in.
GPIO2
SARA-G340
SARA-G350
SARA-U2
23
I/O
GPIO
1.8 V GPIO by default configured to provide the
custom GNSS supply enable function.
See section 1.11 for functional description.
See section 2.8 for external circuit design-in.
GPIO3
SARA-G340
SARA-G350
SARA-U2
24
I/O
GPIO
1.8 V GPIO by default configured to provide the
custom GNSS data ready function.
See section 1.11 for functional description.
See section 2.8 for external circuit design-in.
GPIO4
SARA-G340
SARA-G350
SARA-U2
25
I/O
GPIO
1.8 V GPIO by default configured to provide the
custom GNSS RTC sharing function.
See section 1.11 for functional description.
See section 2.8 for external circuit design-in.
Reserved
RSVD
All
33
N/A
RESERVED pin
This pin must be connected to ground.
See section 2.9
RSVD
SARA-G3
17, 19
N/A
RESERVED pin
Leave unconnected.
See section 2.9
RSVD
SARA-G340
SARA-G350
SARA-U2
31
N/A
RESERVED pin
Internally not connected. Leave unconnected.
See section 2.9
RSVD
SARA-G300
SARA-G310
16, 23,
25-27,
34-37
N/A
RESERVED pin
Pin disabled. Leave unconnected.
See section 2.9
RSVD
SARA-G300
SARA-G310
SARA-U2
44-49
N/A
RESERVED pin
Leave unconnected.
See section 2.9
RSVD
SARA-G300
SARA-G310
62
N/A
RESERVED pin
Leave unconnected.
See section 2.9
Table 4: SARA-G3 and SARA-U2 series modules pin definition, grouped by function

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1.4 Operating modes
SARA-G3 modules have several operating modes. The operating modes defined in Table 5 and described in
detail in Table 6 provide general guidelines for operation.
General Status
Operating Mode
Definition
Power-down
Not-Powered Mode
VCC supply not present or below operating range: module is switched off.
Power-Off Mode
VCC supply within operating range and module is switched off.
Normal Operation
Idle-Mode
Module processor core runs with 32 kHz reference, that is generated by:
The internal 32 kHz oscillator (SARA-G340, SARA-G350 and SARA-U2 series)
The 32 kHz signal provided at the EXT32K pin (SARA-G300 and SARA-G310)
Active-Mode
Module processor core runs with 26 MHz reference generated by the internal oscillator.
Connected-Mode
Voice or data call enabled and processor core runs with 26 MHz reference.
Table 5: Module operating modes definition
Operating
Mode
Description
Transition between operating modes
Not-Powered
Module is switched off.
Application interfaces are not accessible.
Internal RTC operates on SARA-G340/G350,
SARA-U2 if a valid voltage is applied to V_BCKP.
Additionally, a proper external 32 kHz signal
must be fed to EXT32K on SARA-G300/G310
modules to let internal RTC timer running.
When VCC supply is removed, the module enters not-powered mode.
When in not-powered mode, the modules cannot be switched on by
PWR_ON, RESET_N or RTC alarm.
When in not-powered mode, the modules can be switched on applying
VCC supply (see 2.3.1) so that the module switches from not-powered
to active-mode.
Power-Off
Module is switched off: normal shutdown by an
appropriate power-off event (see 1.6.2).
Application interfaces are not accessible.
Internal RTC operates on SARA-G340/G350,
SARA-U2 as V_BCKP is internally generated.
A proper external 32 kHz signal must be fed to
the EXT32K pin on SARA-G300/G310 to let RTC
timer running that otherwise is not in operation.
When the module is switched off by an appropriate power-off event
(see 1.6.2), the module enters power-off mode from active-mode.
When in power-off mode, the modules can be switched on by
PWR_ON, RESET_N or RTC alarm (see 2.3.1): the module switches
from power-off to active-mode.
When VCC supply is removed, the module switches from power-off
mode to not-powered mode.
Idle
The module is not ready to communicate with
an external device by means of the application
interfaces as configured to reduce consumption.
The module automatically enters idle-mode
whenever possible if power saving is enabled by
the AT+UPSV command (see u-blox AT
Commands Manual [3]), reducing power
consumption (see section 1.5.1.4).
The CTS output line indicates when the UART
interface is disabled/enabled due to the module
idle/active-mode according to power saving and
HW flow control settings (see 1.9.1.3, 1.9.1.4).
Power saving configuration is not enabled by
default: it can be enabled by AT+UPSV (see the
u-blox AT Commands Manual [3]).
A proper 32 kHz signal must be fed to the
EXT32K pin of SARA-G300/G310 modules to let
idle-mode that otherwise cannot be reached
(this is not needed for the other SARA-G3 and
SARA-U2 series modules).
The module automatically switches from active-mode to idle-mode
whenever possible if power saving is enabled (see sections 1.5.1.4,
1.9.1.4 and to the u-blox AT Commands Manual [3], AT+UPSV).
The module wakes up from idle to active mode in the following events:
Automatic periodic monitoring of the paging channel for the
paging block reception according to network conditions (see
1.5.1.4, 1.9.1.4)
Automatic periodic enable of the UART interface to receive and
send data, if AT+UPSV=1 power saving is set (see 1.9.1.4)
RTC alarm occurs (see u-blox AT Commands Manual [3], +CALA)
Data received on UART interface, according to HW flow control
(AT&K) and power saving (AT+UPSV) settings (see 1.9.1.4)
RTS input line set to the ON state by the DTE, if HW flow control
is disabled by AT&K3 and AT+UPSV=2 is set (see 1.9.1.4)
DTR input line set to the ON state by the DTE, if AT+UPSV=3
power saving is set (see 1.9.1.4)
USB detection, applying 5 V (typ.) to VUSB_DET input (see 1.9.3)
The connected USB host forces a remote wakeup of the module
as USB device (see 1.9.3)
GNSS data ready: when the GPIO3 pin is informed by the
connected u-blox GNSS receiver that it is ready to send data over
the DDC (I2C) communication interface (see 1.11, 1.9.4)

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Operating
Mode
Description
Transition between operating modes
Active
The module is ready to communicate with an
external device by means of the application
interfaces unless power saving configuration is
enabled by the AT+UPSV command (see
sections 1.5.1.4, 1.9.1.4 and to the u-blox AT
Commands Manual [3]).
When the module is switched on by an appropriate power-on event
(see 2.3.1), the module enters active-mode from not-powered or
power-off mode.
If power saving configuration is enabled by the AT+UPSV command,
the module automatically switches from active to idle-mode whenever
possible and the module wakes up from idle to active-mode in the
events listed above (see idle to active transition description).
When a voice call or a data call is initiated, the module switches from
active-mode to connected-mode.
Connected
A voice call or a data call is in progress.
The module is ready to communicate with an
external device by means of the application
interfaces unless power saving configuration is
enabled by the AT+UPSV command (see
sections 1.5.1.4, 1.9.1.4 and the u-blox AT
Commands Manual [3]).
When a voice call or a data call is initiated, the module enters
connected-mode from active-mode.
When a voice call or a data call is terminated, the module returns to
the active-mode.
Table 6: Module operating modes description
Figure 5 describes the transition between the different operating modes.
Switch ON:
•Apply VCC
If power saving is enabled
and there is no activity for
a defined time interval
Any wake up event described
in the module operating
modes summary table above
Incoming/outgoing call or
other dedicated device
network communication
No RF Tx/Rx in progress,
Call terminated,
Communication dropped
Remove VCC
Switch ON:
•PWR_ON
•RTC alarm
•RESET_N
(SARA-U2)
Not
powered
Power off
ActiveConnected Idle
Switch OFF:
•AT+CPWROFF
•PWR_ON
(SARA-U2)
Figure 5: Operating modes transition

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1.5 Supply interfaces
1.5.1 Module supply input (VCC)
The modules must be supplied via the three VCC pins that represent the module power supply input.
The VCC pins are internally connected to the RF power amplifier and to the integrated Power Management Unit:
all supply voltages needed by the module are generated from the VCC supply by integrated voltage regulators,
including V_BCKP Real Time Clock supply, V_INT digital interfaces supply and VSIM SIM card supply.
During operation, the current drawn by the SARA-G3 and SARA-U2 series modules through the VCC pins can
vary by several orders of magnitude. This ranges from the high peak of current consumption during GSM
transmitting bursts at maximum power level in connected-mode (as described in section 1.5.1.2), to the low
current consumption during low power idle-mode with power saving enabled (as described in section 1.5.1.4).
1.5.1.1 VCC supply requirements
Table 7 summarizes the requirements for the VCC module supply. See section 2.2.1 for all the suggestions to
properly design a VCC supply circuit compliant to the requirements listed in Table 7.
VCC supply circuit affects the RF compliance of the device integrating SARA-G3 and SARA-U2
series modules with applicable required certification schemes as well as antenna circuit design.
Compliance is guaranteed if the VCC requirements summarized in the Table 7 are fulfilled.
For the additional specific requirement for SARA-G350 ATEX modules integration in potentially explosive
atmospheres applications, see section 2.14.
Item
Requirement
Remark
VCC nominal voltage
Within VCC normal operating range:
3.35 V min. / 4.50 V max for SARA-G3 series
3.30 V min. / 4.40 V max for SARA-U2 series
The module cannot be switched on if VCC voltage value
is below the normal operating range minimum limit.
Ensure that the input voltage at VCC pins is above the
minimum limit of the normal operating range for at least
more than 3 s after the module switch-on.
VCC voltage during
normal operation
Within VCC extended operating range:
3.00 V min. / 4.50 V max for SARA-G3 series
3.10 V min. / 4.50 V max for SARA-U2 series
The module may switch off when VCC voltage drops
below the extended operating range minimum limit.
Operation above extended operating range limit is not
recommended and may affect device reliability.
VCC average current
Considerably withstand maximum average current
consumption value in connected-mode conditions
specified in the SARA-G3 series Data Sheet [1] and in
the SARA-U2 series Data Sheet [2].
The maximum average current consumption can be
greater than the specified value according to the actual
antenna mismatching, temperature and VCC voltage.
See 1.5.1.2, 1.5.1.3 for connected-mode current profiles.
VCC peak current
Withstand the maximum peak current consumption
specified in the SARA-G3 series Data Sheet [1] and in
the SARA-U2 series Data Sheet [2].
The specified maximum peak of current consumption
occurs during GSM single transmit slot in 850/900 MHz
connected-mode, in case of mismatched antenna.
See 1.5.1.2 for 2G connected-mode current profiles.
VCC voltage drop
during 2G Tx slots
Lower than 400 mV
VCC voltage drop directly affects the RF compliance with
applicable certification schemes.
Figure 7 describes VCC voltage drop during Tx slots.
VCC voltage ripple
during 2G/3G Tx
Lower than 30 mVpp if fripple ≤200 kHz
Lower than 10 mVpp if 200 kHz < fripple ≤400 kHz
Lower than 2 mVpp if fripple > 400 kHz
VCC voltage ripple directly affects the RF compliance with
applicable certification schemes.
Figure 7 describes VCC voltage ripple during Tx slots.
VCC under/over-shoot
at start/end of Tx slots
Absent or at least minimized
VCC under/over-shoot directly affects the RF compliance
with applicable certification schemes.
Figure 7 describes VCC voltage under/over-shoot.
Table 7: Summary of VCC supply requirements