OptConnect EMA-L4-1-XX-A-A Installation instructions

OptConnect ema™
Hardware Guide
V1.1 Updated: September 2019

© OptConnect Management, LLC 2019. All rights reserved. Revision 1.1
2
© OptConnect Management, LLC 2019. All rights reserved.
OptConnect Management, LLC provides this documentation in support of its products for the internal use of its current and prospective
customers. The publication of this document does not create any other right or license in any party to use any content contained in or
referred to in this document and any modification or redistribution of this document is not permitted.
While efforts are made to ensure accuracy, typographical and other errors may exist in this document. OptConnect Management, LLC
reserves the right to modify or discontinue its products and to modify this and any other product documentation at any time.
All OptConnect products are sold subject to its published Terms and Conditions, subject to any separate terms agreed with its
customers. No warranty of any type is extended by publication of this documentation, including, but not limited to, implied warranties
of merchantability, fitness for a particular purpose and non-infringement.
OptConnect is a trademark, and OptConnect ema™ is a trademark, of OptConnect Management, LLC. All trademarks, service marks and
similar designations referenced in this document are the property of their respective owners.

© OptConnect Management, LLC 2019. All rights reserved. Revision 1.1
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Table of Contents
Table of Contents 3
1. Introduction 5
1.1 Scope 5
1.2 Contact Information 5
1.3 Orderable Part Numbers 5
1.4 Additional Resources 5
1.5 Product Overview 6
1.6 Block Diagram 7
2. Technical Specifications 8
2.1 Electrical Specifications 8
2.1.1 Absolute Maximum Ratings 8
2.1.2 Typical Power Consumption 8
2.1.3 Module Pinout for Connectors J1 and J2 9
2.1.4 Module Pinout for Connectors J3, X1, X2 12
2.2 RF Specifications 12
2.2.1 TX Power 12
2.2.2 RX Sensitivity 13
2.2.3 4G LTE Uplink and Downlink Speeds 13
2.3 Mechanical Characteristics 13
2.3.1 Mechanical Specifications 13
2.3.2 Mating Connectors 14
2.3.3 Mechanical Drawings 14
2.3.3.1 Modem Dimensions 14
2.3.3.2 SIM Card Rib Drawings 15
2.3.4 Device Placement 15
2.3.5 Environmental Specifications 15
3. Design Considerations 15
3.1 Power Supply Requirements 16
3.1.1 Power Supply Design Guidelines 16
3.2 Serial Communications 17
3.2.1 OptConnect ema™ Management UART 17
3.2.2 OptConnect ema™ Modem UART Interface 18
3.2.3 USB Interface 18
3.3 VREF 18
3.4 Power Control 19

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3.4.1 ON_OFF 19
3.4.2 Shutdown 19
3.4.3 nRESET_REQUEST 19
3.5 Network Status Monitoring 19
3.6 Firmware Updates Over the Air (FOTA) 20
3.7 Cellular Antenna Requirements 20
3.7.1 Primary Antenna Requirements 20
3.7.2 Diversity Antenna Requirements 21
3.7.3 Antenna Placement 22
3.7.4 Recommended Antennas 22
3.8 Reference Designs 23
4. Basic Modem Operation 23
4.0 Power up 23
4.1 Standard operation 23
4.2 AT Commands Not to Use 23
5. Mounting Guidelines 24
5.0 Board-to-Board Connectors 24
5.0.1 Mechanical Retention 24
5.1 Solder to Board Connection 25
6. Regulatory Information 26
6.0 Carrier Specific Certifications 26
6.1 Export Control Classification Number (ECCN) 26
6.2 Harmonized Tariff Schedule Code 26
6.3 RoHS Compliance 26
6.4 Interference Statement 27
6.5 FCC & IC Compliance 27
6.6 Wireless Notice 27
6.7 Modification Statement 28
6.8 End Product Labeling Requirements 28
7. Revision History 29

© OptConnect Management, LLC 2019. All rights reserved. Revision 1.1
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1. Introduction
1.1 Scope
This document serves as a hardware guide for the OptConnect ema™ cellular modem.
1.2 Contact Information
For more information regarding OptConnect ema™ contact OptConnect Sales at 1.877.678.3343 ext. 2020
during normal business hours. For technical support contact OptConnect Customer Care Center at
1.877.678-3343 ext. 2021 from 8 am till 9 pm MST Monday through Saturday.
1.3 Orderable Part Numbers
Orderable
Device
Modem
Firmware
Revision
Operating
Temperature
LTE Bands
3G
UMTS
Network
Region
EMA-L4-1-XX-A-A
20.00.005
-40 to +85˚C
FDD B2, B4, B5,
B12, B13
B2, B5
AT&T,
Verizon
North America
EMA-L4-1-US-B-A
20.00.005
-40 to +85˚C
FDD B2, B4, B5,
B12, B13
B2, B5
AT&T,
Verizon
United States
Unless instructed otherwise EMA-L4-1-XX-A-A will utilize AT&T as the primary carrier and Verizon as the
secondary carrier. Unless instructed otherwise, EMA-L4-1-US-B-A will utilize Verizon as the primary carrier
and AT&T as the secondary carrier.
Orderable
Device
Description
Operating
Temperature
Region
EMA-ZZ-1-XX-Z-B
ema: Play Evaluation Kit, OptConnect ema™ evaluation
platform
-40 to +85˚C
North America
EMA-L4-1-XX-A-B
ema: Play Evaluation Kit, OptConnect ema™ evaluation
platform, EMA-L4-1-XX-A-A ema modem included
-40 to +85˚C
North America
EMA-L4-1-US-B-B
ema: Play Evaluation Kit, OptConnect ema™ evaluation
platform, ema EMA-L4-1-US-B-A ema modem included
-40 to +85˚C
United States
1.4 Additional Resources
OptConnect ema™ is supported by a full range of documentation in addition to this Hardware Guide;
including User Guides and Application Notes as well as an ema: Play Evaluation Kit User Guide and related
code samples. The latest versions of these resources can be found at http://optconnect.com/ema .

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1.5 Product Overview
OptConnect ema™ is a fully end user certified modem with built in intelligence for autonomous
monitoring, management, and self-healing. Its Embedded Managed Modem Architecture enables
customers to rapidly design and deploy cellular connected solutions while eliminating the delays and
complexities of typical IoT deployments. Each OptConnect ema™ modem comes integrated with an
industry leading suite of OptConnect managed services that include:
⚫OptConnect SIM cards
⚫Cellular data plans
⚫Connectivity monitoring and management
⚫Device management portal
⚫24x7x365 technical support
⚫Warranty replacement services
⚫Simple ready-to-use back office API cloud integrations
⚫Logistics
⚫Fast fulfillment
OptConnect ema™ is fully certified as an end user modem and eliminates the need for a customer’s host
board and equipment to be certified by carriers. By using the OptConnect ema™ modem, customers can
introduce new board designs as often as necessary and never have to send their designs through a time
consuming and costly certification process. OptConnect ema™ is a complete solution for a headache-free
IoT strategy.

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1.6 Block Diagram

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2. Technical Specifications
2.1 Electrical Specifications
2.1.1 Absolute Maximum Ratings
Parameter
Signal
Maximum Rating
Main Power Supply
VCC
4.5V
I/O Voltage Reference
VREF
5.5V
2.1.2 Typical Power Consumption1
Mode
Signal
Attenuation
(dB)
RSRQ
RSRQ
Peak
Current
(mA)
Average
Current
(mA)
Charge
Consumed
(mAh)
Measurement Notes
Active
Socket Dial
0
-57
-8
248.636
139.666
75.070
(µAh)
Tested at: 3.8V
Time elapsed: 1.935 s
Test: Open socket, HTTP POST,
read HTTP response, close socket.
20
-75
-8
722.435
169.771
95.968
(µAh)
(µAh)(µA
Tested at: 3.8V
Time elapsed: 2.035 s
Test: Open socket, HTTP POST,
read HTTP response, close socket.
40
-95
-8
647.929
178.169
101.457
(µAh)
Tested at: 3.8V
Time elapsed: 2.050 s
Test: Open socket, HTTP POST,
read HTTP response, close socket.
Idle,
Registered
on network.
0
-57
-8
555.222
67.915
5.638
Tested at: 3.8V
Time elapsed: 300 s
Test: 300 second measurement
while modem is registered on
network.
Off
0
N/A
N/A
16.259
16.259
16.259
Tested at: 3.8V
Time elapsed: 300 s
Test: Module powered off with
AT#SHDN.
1. The measurements presented here were taken from Engineering Samples and are subject to
change.

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2.1.3 Module Pinout for Connectors J1 and J2
The following table details the pinout of the OptConnect ema™ modem and lists the recommended
ratings for the modem interface on connectors J1 and J2. More details and design requirements for these
pins are documented in Section 3.
Pin
Name
Direction
Description
Min
Typ.
Max
1
(J1-1)
VCC
Input
Main power supply pin.
3.4V
3.8V
4.2V
2
(J1-2)
DOUT
Output
Modem UART data
out, I/O level tied to
VREF.
VOL
0
0.60V
VOH
VREF x
0.7
VREF
3
(J1-3)
DIN
Input
Modem UART data in,
I/O level tied to VREF.
VREF Range
VIL (max)
VIH (min)
1.8V to 1.95V
VREF x
0.35V
VREF x
0.65
2.3V to 2.7V
0.7V
1.7V
3.0V to 3.6V
0.8V
2V
4.5V to 5.5V
VREF x
0.3V
VREF x
0.7
4
(J1-4)
GND
Input
Ground Pin.
0V
5
(J1-5)
nRESET_
REQUEST
Input
Reset request signal.
VIL
0V
0.50V
VIH
1.30V
1.8V

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6
(J1-6)
VUSB
Input
USB connection detection.
4.4V
5.0V
5.25V
Pin
Name
Direction
Description
Min
Typ.
Max
7
(J1-7)
USB_P
I/O
USB differential data bus (+).
Requires differential impedance of 90Ω.
0V
5.25V
8
(J1-8)
USB_N
I/O
USB differential data bus (-).
Requires differential impedance of 90Ω.
0V
5.25V
9
(J1-9)
DTR
Input
“Data Terminal Ready”
hardware flow control
input.
VREF Range
VIL (max)
VIH (min)
1.8V to 1.95V
VREF x
0.35V
VREF x
0.65
2.3V to 2.7V
0.7V
1.7V
3.0V to 3.6V
0.8V
2V
4.5V to 5.5V
VREF x
0.3V
VREF x
0.7
10
(J1-10)
GND
Input
Ground Pin.
0V
11
(J2-1)
GND
Input
Ground Pin.
0V
12
(J2-2)
CTS
Output
“Clear to Send”
hardware flow control
output.
VOL
0
0.60V
VOH
VREF x
0.7
VREF
13
(J2-3)
STATUS
Output
Status pin. High when
modem is ready for
use.
VOL
0
0.60V
VOH
VREF x
0.7
VREF

© OptConnect Management, LLC 2019. All rights reserved. Revision 1.1
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14
(J2-4)
VREF
Input
Voltage reference for offboard I/O
signals.
1.8V
5.5V
15
(J2-5)
GND
Input
Ground Pin.
0V
Pin
Name
Direction
Description
Min
Typ.
Max
16
(J2-6)
RTS
Input
“Request to Send”
hardware flow control
input.
VREF Range
VIL (max)
VIH (min)
1.8V to 1.95V
VREF x
0.35V
VREF x
0.65
2.3V to 2.7V
0.7V
1.7V
3.0V to 3.6V
0.8V
2V
4.5V to 5.5V
VREF x
0.3V
VREF x
0.7
17
(J2-7)
ema_DOUT
Output
Management MCU
serial data output
signal.
VOL
0
0.60V
VOH
VREF x
0.7
VREF
18
(J2-8)
ema_DIN
Input
Management MCU
serial data input signal.
VREF Range
VIL (max)
VIH (min)
1.8V to 1.95V
VREF x
0.35V
VREF x
0.65
2.3V to 2.7V
0.7V
1.7V
3.0V to 3.6V
0.8V
2V
4.5V to 5.5V
VREF x
0.3V
VREF x
0.7
19
(J2-9)
RING_IND
Output
“Ring Indicator”
output pin.
VOL
0
0.60V

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VOH
VREF x
0.7
VREF
20
(J2-10)
ON_OFF
Input
On/Off signal.
Internally pulled up to
1.8V.
VIL
0V
0.50V
VIH
1.30V
1.8V
Additional information on OptConnect ema™ pinout is available in Section 3.
2.1.4 Module Pinout for Connectors J3, X1, X2
Connector Designator
Description
Connector Location
J3
Dual Micro SIM Connector
Bottom Side of Modem
X1
Primary Cellular Antenna Connection
Top side of Modem
X2
Diversity Cellular Antenna Connection
Top side of Modem
2.2 RF Specifications
2.2.1 TX Power
Available Cellular Technologies and Output Power
4G LTE Technology
4G LTE CAT 4
4G LTE TX Output Power
0.2 W (Class 3)
23 dBm
3G Technology
WCDMA
3G TX Output Power
(all bands)
0.25 W (Class 3)
24 dBm

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2.2.2 RX Sensitivity
Available Cellular Technologies and RX Sensitivity
4G
LTE FDD B2
-103.0 dBm
LTE FDD B4
-102.5 dBm
LTE FDD B5
-103.0 dBm
LTE FDD B12
-103.0 dBm
LTE FDD B13
-103.0 dBm
3G
WCDMA FDD B2
-113.0 dBm
WCDMA FDD B5
-113.0 dBm
2.2.3 4G LTE Uplink and Downlink Speeds
4G LTE Peak Uplink and Downlink Speeds
Uplink
50 Mbps*
Downlink
150 Mbps*
Actual network speeds will depend on local network conditions
2.3 Mechanical Characteristics
2.3.1 Mechanical Specifications
Parameter
Typical
Unit
Dimensions
29.00 x 33.78 x 10.67
mm
1.14 x 1.33 x 0.42
inches
Weight
12
Grams
0.4
oz
Socket Insertion/Removal
hundreds
Cycles

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2.3.2 Mating Connectors
Connector
Designator
Manufacturer
Populated on ema
Recommended
Mate
Mate Manufacturer
J1, J2
3M
951110-2530-AR-PR
950510-6102-AR
3M
Acceptable alternate:
NPPN101BFCN-RC
Sullins Connector
Solutions
X1, X2
Hirose
U.FL-R-SMT(10)
CAB.011
Taoglas
2.3.3 Mechanical Drawings
2.3.3.1 Modem Dimensions

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2.3.3.2 SIM Card Rib Drawings
2.3.4 Device Placement
⚠Make sure the OptConnect ema™ modem is installed in the correct orientation
into the host board. Failure to do so will damage the device and void the
warranty.
2.3.5 Environmental Specifications
Parameter
Min
Typical
Max
Unit
Note
Operating
Temperature
-40
+25
+85
˚C
Storage Temperature
-40
+25
+85
˚C
Operating Humidity
20
90
%
Non-condensing
3. Design Considerations
The following sections detail various design considerations that system designers should follow when
designing an OptConnect ema™ modem into their system. OptConnect offers reference schematics and
PCB layout designs, and can review designs for customers integrating an OptConnect ema™ modem into
their system. For more details please reach out to OptConnect’s product support team at 1.877.678.3343.

© OptConnect Management, LLC 2019. All rights reserved. Revision 1.1
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3.1 Power Supply Requirements
OptConnect ema™ modems will regularly consume significant amounts of current on the main power
supply input Pin 1 (VCC). For LTE and WCDMA transmits and receives, this current consumption can be up
to 1 A.
The baseboard power supply should be designed to support peak currents of at least 1.5 Amps to ensure
enough power is available for the modem during high current operations.
A 0.1 µF & 100 µF low ESR ceramic capacitor should be placed near Pin 1 (VCC) of the modem to ensure
that a local energy supply is available, with a low inductance path to the VCC pin.
Parameter
Value
Nominal Supply Voltage
3.8V
Operating Voltage Range
3.40V to 4.20V
OptConnect ema™ modems have a normal operating voltage range of 3.40V to 4.20V, with a
recommended input voltage of 3.80V.
Extreme care must be taken when operating the modem to ensure it stays within its operating voltage
range. If there is a voltage drop or overshoot that exceeds the limits of the operating voltage range, it
may cause damage to the modem and void the modem’s warranty.
Customers should thoroughly test their power supply systems to ensure they are capable of meeting the
rigorous current demands of an LTE modem without falling outside of the operating voltage range.
3.1.1 Power Supply Design Guidelines
When designing the power supply for an OptConnect ema™ modem it is recommended to adhere to the
following design guidelines:
⚫For most applications, a switching power supply is recommended to supply power to the modem.
This is because switching power supplies are able to rapidly respond to the sudden current
demands of an LTE modem. To ensure compatibility with OptConnect ema™ modems, it is
recommended to use a switching regulator capable of supporting up to 1.5A. Example designs
using a switching DC/DC regulator can be found in OptConnect ema™ reference designs.
⚫To reduce EMI from the switching regulator, it is important to follow the design guidelines from
the device manufacturer.
⚫Bypass ceramic capacitors (low ESR) with adequate capacity must be placed near the input to Pin
1 (VCC) of the modem. It is recommended that the capacitor have a rated voltage of at least 2x
the input voltage to the modem. A minimum of a 100 µF & 0.1 µF capacitor is recommended. The
0.1 µF capacitor should be placed as close as possible to Pin 1 (VCC) of the modem, followed by
the 100 μF capacitor.

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⚫The PCB traces from the power regulator and the bypass capacitors must be at least 80 mils to
ensure that there is a low impedance power delivery circuit available to the modem. This ensures
that no significant voltage drops occur. Try to keep the trace(s) as short as possible.
⚫A dedicated ground plane is recommended.
⚫Direct connect from pours should be used in the power supply sections.
⚫Power supply input cables should be kept away from noise sensitive lines, such as antennas.
OptConnect offers the ema:Play Evaluation Kit in order to assist customers with their designs. Reference
schematics and layout examples can be found at http://optconnect.com/ema .
While prototyping with the OptConnect ema™ modem, it is recommended to use the ema:Play Evaluation
Kit, as opposed to a breadboard setup.
Prototyping with Cellular Modems and Modules:
Power supply and power management are critical to the performance of production cellular
products and to their pre-production prototypes. The OptConnect ema:Play Evaluation Kit
implements the necessary power management techniques to enable customers to easily prototype
their equipment that will incorporate an OptConnect ema™ modem. OptConnect strongly
recommends that prototype designers do not utilize a simple breadboard setup to test their
designs as improper power management can make the ema modem temporarily or permanently
inoperable. In addition to the necessary power management features, the OptConnect ema:Play
Evaluation Kit includes assets to allow robust firmware development and debugging, sensors for
example instrumentation, and source code for example applications.
3.2 Serial Communications
OptConnect ema™ modems have two UART interfaces; one for the modem and one for the OptConnect
ema™ management Microcontroller Unit (MCU). OptConnect ema™ modems also support a USB
connection. Customers integrating the OptConnect ema™ modem are required to connect to the
OptConnect ema™ Management UART interface and either one of the modem’s UART or USB interfaces.
The modem’s UART interface is targeted for applications using lower speed 8/16/32 bit MCU’s that do not
have a USB interface or easily available USB interface drivers. The modem’s USB interface is intended for
use by higher end systems with a native USB interface controller or operating system (Single board
computers, Linux/Windows, etc.).
For designs that are not using the modem’s USB interface, it is recommended that designers include test
points or a non-populated USB connector footprint in their designs as well. This allows for future access
to the modem’s USB interface to enable easy debugging and firmware updates.
3.2.1 OptConnect ema™ Management UART
The OptConnect ema™ Management UART resides on Pins 17 (ema_DOUT) and 18 (ema_DIN). This
interface connects to the OptConnect ema™ Management MCU on the modem that controls the behind
the scenes operations of the modem. This interface serves as a status and control interface for the
OptConnect ema™ modem’s Management MCU. Host systems must monitor this interface for URC’s

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(Unsolicited Result Codes) that will indicate modem status and behaviors. This interface defaults to 19200
8N1 baud. This interface is also reserved for future feature support. Please reference the OptConnect
ema™ Management UART AT Command Manual for further details.
3.2.2 OptConnect ema™ Modem UART Interface
The modem UART interface resides on Pins 2 (DOUT) and 3 (DIN) and is a serial interface into the cellular
module on the modem. This interface can be used to send and receive data over the cellular network.
The baud rate defaults to 115200 Baud 8N1. If a different baud rate is required, it can be changed with the
AT+IPR command as defined in the AT command manual. The modem also supports RTS/CTS flow
control on Pins 12 (CTS) and 16 (RTS).
By default, the modem has flow control enabled. To modify the flow control setting, please see the
AT+IFC command in the AT command manual. It is recommended that any designs using the modem
UART interface connect the RTS/CTS flow control lines to the host and enable them in their application.
3.2.3 USB Interface
The OptConnect ema™ modem also supports a USB 2.0 interface on Pins 6 (VUSB), 7 (USB_P), and 8
(USB_N) which connects into the cellular module on the modem. Monitoring of the OptConnect ema™
Management MCU is not available through this interface.
Systems connecting to the modem’s USB interface must observe proper design practices for connecting
to a high-speed USB device including, but not limited to, the following:
⚫The USB D± traces should be routed as a 90-ohm impedance differential pair.
⚫The USB D± traces should be length matched.
⚫USB trace lengths should be minimized.
⚫USB differential pairs should be carefully routed to ensure they have a continuous return path
beneath the traces. Do not route differential pairs over splits in ground or power planes.
⚫If the USB signals will be used off-board, ESD protection should be implemented near the off-
board connector.
Pin 6 (VUSB) is used to detect if a USB host controller has been connected to the modem. This pin has an
internal pulldown and must have a voltage between 4.4V and 5.25V applied to it in order to activate the
USB interface. The VUSB pin will draw less than 5mA when connected. VUSB must be disconnected or
asserted to ground before activating Power Saving Mode.
3.3 VREF
Pin 14 (VREF) drives the input voltage side of onboard buffers which convert external I/O voltages from
the VREF range to the modem’s internal voltage range in order to interface with the modem’s systems.
System designers should connect the reference voltage of their system to this pin. The VREF signal will
draw less than 5mA when the modem is powered.

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3.4 Power Control
3.4.1 ON_OFF
Pin 20 (ON_OFF) is used to trigger the modem to turn on and off. To turn the modem on, drive the
ON_OFF signal to ground and hold it there.
The ON_OFF signal is a 1.8V IO and must be driven with an open drain/collector output or external
discrete open drain/collector transistor. Do not power this pin or apply a pullup resistor, as doing so may
prevent the modem from booting, or may cause damage to the modem.
3.4.2 Shutdown
The modem must be shut down in a controlled manner, so as to gracefully disconnect it from the network
and to safely power down the cellular module on the modem. Failure to do so violates carrier
requirements. In rare events, failure to properly shut down the modem could render the modem
inoperable due to firmware corruption.
The modem can be gracefully shut down by releasing Pin 20 (ON_OFF) from ground. This method will
force the modem to issue a detach request to the network, which informs the network that the device will
be unreachable for an indefinite time. After issuing this request, the modem will power down.
3.4.3 nRESET_REQUEST
In the event that the modem becomes unresponsive, Pin 5 (nRESET_REQUEST) can be used to request the
OptConnect ema™ Management MCU to reset the modem.
To request a modem reset, the nRESET_REQUEST signal should be driven to ground for at least one (1)
second, and then released. The signal is internally pulled up to the modem’s internal 1.8V rail and should
be driven with an open drain/collector. Do not drive this signal high or apply a pull up resistor.
When the nRESET_REQUEST signal is detected by the OptConnect ema™ Management MCU, it will
attempt to properly reset the modem with a controlled shutdown. If that fails it will unconditionally
shutdown the modem.
Network providers request that a device gracefully detach from the network before shutting down.
Unconditional shutdowns violate this requirement. As such, the OptConnect ema™ management MCU
attempts to use an unconditional reset as an emergency reset only when the modem is not responding to
commands.
In high noise (high EMI) environments, it is recommended that designers place a 0.01 µF –0.1 µF
capacitor on the nRESET REQUEST signal near the J1 connector.
3.5 Network Status Monitoring
OptConnect ema™ modems feature a status LED that is controlled by the OptConnect ema™
Management MCU. The behavior of this LED is described in the table below:

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Device Status
LED Behavior
Device Off
Permanently off
Not Registered on Network
Permanently on
Registered on Network, Idling
Blinking, 1 second on, 2 seconds off
Registered on Network, and Power Saving
LED blinks in sync with network paging activity.
Depends on the active power saving mode.
3.6 Firmware Updates Over the Air (FOTA)
LTE networks are constantly being updated, improved, and enhanced with new features. As a result,
carriers are making frequent network changes. Most changes will not negatively affect devices connected
to those networks, but occasionally an update will prevent an unprepared device from re-connecting to
the network permanently.
To account for these future changes, FOTA (Firmware Over the Air) capability is added to cellular modules
by each module manufacturer. OptConnect ema™ supports this functionality, and automatically manages
the modems FOTA processes. The OptConnect ema™ modem has the capability to update the on-board
cellular module as well as the OptConnect ema™ Management MCU using microFOTA.
When a FOTA update is triggered, the modem will output FOTA specific URC’s over the OptConnect
ema™ Management UART interface to notify the host system that FOTA is in progress. When a FOTA
update is in progress the host system must keep the modem powered and connected until the process is
complete.
Failure to accommodate FOTA processes may result in interruptions in cellular connectivity in the event of
network changes. If a device can no longer access the network, FOTA cannot be used to remedy the
problem. The only way to recover functionality is to physically retrieve the device and update its firmware.
FOTA Instructions are available by contacting OptConnect’s product support team at 1.877.678.3343.
3.7 Cellular Antenna Requirements
The OptConnect ema™ modem supports a primary cellular antenna connection, and a diversity antenna
connection. These connectors are U.FL connectors, and are labeled as X1 and X2, respectively. To fulfill
carrier certification requirements, system integrators are required to use both the primary and diversity
antennas in their application.
Note: many antennas will require the use of a U.FL to SMA cable, such as the Taoglas CAB.011.
3.7.1 Primary Antenna Requirements
Depending on the frequency band(s) provided by the network operator, the customer shall use the most
suitable antenna for that/those band(s):