Huawei MG301 Installation instructions

HUAWEI MG301 B2B Module
Hardware Guide
Issue 06
Date 2014-06-20

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HUAWEI MG301 B2B Module
HardwareGuide Contents
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6
Contents
1Introduction....................................................................................................................................8
1.1 Overview ...........................................................................................................................................8
2Overall Description ......................................................................................................................9
2.1 About This Chapter ........................................................................................................................... 9
2.2 Function Overview............................................................................................................................ 9
2.3 Application Block Diagram .............................................................................................................. 11
2.4 Circuit Block Diagram ..................................................................................................................... 11
3Description of the Application Interfaces .............................................................................13
3.1 About This Chapter ........................................................................................................................ 13
3.2 B2B Connector Interface ............................................................................................................... 13
3.3 Power Interface ............................................................................................................................. 16
3.3.1 Overview ............................................................................................................................... 16
3.3.2 VBAT Interface ...................................................................................................................... 17
3.3.3 VCOIN Interface ................................................................................................................... 18
3.3.4 VIO Interface ......................................................................................................................... 18
3.4 Power-On and Power-Off Time Sequence .................................................................................... 18
3.4.1 Overview ............................................................................................................................... 18
3.4.2 Power-On Time Sequence .................................................................................................... 19
3.4.3 Power-Off Time Sequence .................................................................................................... 20
3.4.4 RESET .................................................................................................................................. 20
3.5 Signal Control Interface ................................................................................................................. 20
3.5.1 Overview ............................................................................................................................... 20
3.5.2 Input Signal Control Pins ...................................................................................................... 21
3.5.3 Output Signal Control Pin ..................................................................................................... 22
3.6 UART Interface .............................................................................................................................. 23
3.6.1 Overview ............................................................................................................................... 23
3.6.2 Circuit Recommended for the UART Interface ..................................................................... 24
3.7 SIM Card Interface ........................................................................................................................ 25
3.7.1 Overview ............................................................................................................................... 25
3.7.2 Circuit Recommended for the SIM Card Interface ................................................................ 26
3.8 Audio Interface ............................................................................................................................... 27
4Antenna Interface .......................................................................................................................29

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4.1 About This Chapter ........................................................................................................................ 29
4.2 Antenna Installation ....................................................................................................................... 29
4.3 Coaxial Cable and RF Connector .................................................................................................. 30
4.4 ESD Protection for the Antenna Interface ...................................................................................... 32
4.5 RF Specifications of the Antenna Interface .................................................................................... 32
4.6 Specifications of the Antenna Interface ......................................................................................... 34
5Electrical and Reliability Features ..........................................................................................35
5.1 About This Chapter ........................................................................................................................ 35
5.2 Extreme Working Conditions ......................................................................................................... 35
5.3 Operating and Storage Temperatures and Humidity ...................................................................... 36
5.4 Electrical Criteria of Application Interfaces .................................................................................... 36
5.5 Power Supply Features ................................................................................................................. 40
5.5.1 Input Power Supply ............................................................................................................... 40
5.5.2 Working Current .................................................................................................................... 40
5.6 Reliability Features ........................................................................................................................ 42
5.7 ESD Features ................................................................................................................................ 44
6Mechanical Specifications ........................................................................................................45
6.1 Overview ....................................................................................................................................... 45
6.2 Dimensions .................................................................................................................................... 45
6.3 Dimensions of the B2B Connector ................................................................................................ 46
6.4 MG323 Module Installation Description ......................................................................................... 48
6.5 Specification Selection for Fasteners ............................................................................................. 50
7Appendix A Circuits of Typical Interfaces ............................................................................52
8Appendix B Acronyms and Abbreviations ............................................................................53
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HUAWEI MG301 B2B Module
HardwareGuide Introduction
8
1Introduction
1.1 Overview
This document describes the hardware application interfaces and air interfaces that
are provided when the Huawei MG301 B2B module (hereinafter referred to as
the MG323 module) is used.
The MG301 B2B module can pin to pin replace MG323 module
This document helps you to understand the interface specifications, electrical
features, and related product information of the MG301 B2B module.
MG301 B2B Front MG301 B2B Back
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HUAWEI MG301 B2B Module
HardwareGuide Overall Description
9
2Overall Description
2.1 About This Chapter
This chapter gives a general description of the MG301 B2B module and provides:
Function Overview
Application Block Diagram
Circuit Block Diagram
2.2 Function Overview
Table 2-1 Feature
Feature
Description
Working bands
Four supported frequency bands: GSM850 MHz/900 MHz/1800
MHz/1900 MHz
Maximum
transmission
power
GSM850 Class 4 (2 W)
EGSM900 Class 4 (2 W)
DCS1800 Class 1 (1 W)
PCS1900 Class 1 (1 W)
Receiver
sensitivity
< –107 dBm
Operating
Temperature
Normal operating temperature: –20°C to +70°C
Extended operating temperature[1]: –40°C to +85°C
Ambient
temperature for
storage
–40°C to +85°C
Power voltage
3.3 V to 4.8 V (3.8 V is recommended.)
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Feature
Description
Power
consumption
(current)
Power-off current: 50 µA
Average
standby current
DRX=2
< 3.0 mA
DRX=5
< 2.5 mA
DRX=9
< 2.0 mA
GPRS Class 10 (maximum): 455 mA
Protocols
GSM/GPRS Phase2/2+
AT commands
See the HUAWEI MG301 Series Wireless Module AT Command
Interface Specification.
Application
interface (50-
pin B2B
connector)
UART1 (supporting 8-wire UART) and UART0 (2-wire UART)
One standard Subscriber Identity Module (SIM) card interface
(Class B or Class C)
Interfaces for two analog audio channels
USB Interface
Network status light-emitting diode (LED) control interface
Antenna
interface
Hirose U.FL-R-SMT-1(80) 50 Ω antenna connector
Antenna pad
Voice services
Two analog voice channels
SMS
New message alert, text message receiving, and text message
sending
Management of text messages: read messages, delete
messages, storage status, and message list
Support for the protocol data unit (PDU) mode
GPRS
GPRS CLASS 10
Encoding schemes: CS 1, CS 2, CS 3, and CS 4
Maximum downlink transmission rate: 85.6 kbps
Maximum uplink transmission rate: 42.8 kbps
Packet Broadcast Control Channel (PBCCH)
Embedded with TCP/IP protocols, supporting multiple links
Circuit
Switched Data
(CSD) data
services
CSD data services at the maximum rate of 9.6 kbit/s
Physical
features

Dimensions (L × W × H): 35 mm × 32.5 mm × 3.05 mm

Weight: 5.8 g
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HardwareGuide Overall Description
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Feature
Description
Certification
information
Restriction of the use of certain Hazardous Substances (RoHS),
European Conformity (CE), Federal Communications
Commission (FCC), CMIIT, China Compulsory Certification
(CCC), GCF (GSM Certification Forum)
.
[1]:The temperatures outside of the range –20°C to +70°C; the module might slightly deviate
from 3GPP TS 45.005 specifications.
2.3 Application Block Diagram
Figure 2-1 shows the application block diagram of the MG301 B2B module.
Figure 2-1 Application block diagram of the MG301 B2B module
2.4 Circuit Block Diagram
The circuit block diagram and major functional units of the MG301 B2B module contain
the following parts:
Baseband controller
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HardwareGuide Overall Description
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Power management
Multi-chip package (MCP) memory
Radio frequency (RF) transceiver
26 MHz clock
32 kHz clock
RF front-end modules
Receive filter
Figure 2-2 Circuit block diagram of the MG301 B2B module
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HUAWEI MG301 B2B Module
HardwareGuide Description of the Application Interfaces
3Description of the Application Interfaces
3.1 About This Chapter
This chapter mainly describes the external application interfaces of the MG301
module, including:
B2B Connector Interface
Power Interface
Power-On and Power-Off Time Sequence
Signal Control Interface
UART Interface
SIM Card Interface
Audio Interface
USB Interface
3.2 B2B Connector Interface
The MG301 B2B module uses a 50-pin B2B connector as its external interface. For details
about the model and dimensions of the B2B connector, see “6.3 Dimensions of the
B2B Connector”.
Figure 3-1 shows the sequence and definitions of pins on the 50-pin B2B signal
interface of the MG301 B2B module.
Figure 3-1 Sequence and definitions of pins on the B2B signal interface
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HUAWEI MG301 B2B Module
HardwareGuide Description of the Application Interfaces
Table 3-1 Definitions of pins on the B2B connector
Pin
No.
Pin Name
I/O
Description
DC Characteristics (V)
Normal
MUX
Min.
Tpy.
Max
1
SIM_CLK
-
O
Clock signal of the SIM
card
-
1.80/2.90
-
2
INTEAR_N
-
AO
Negative pole of the
output of handset
speaker
-
-
-
3
VSIM
-
P
Power supply of the
SIM card
-
1.80/2.90
-
4
INTEAR_P
-
AO
Positive pole of the
output of handset
speaker
-
-
-
5
SIM_DATA
-
I/O
Data signal of the SIM
card
-
1.80/2.90
-
6
EXTEAR_P
-
AO
Positive pole of the
output of headset
speaker
-
-
-
7
SIM_RST
-
O
Reset signal of the SIM
card
-
1.80/2.90
-
8
EXTEAR_N
-
AO
Negative pole of the
output of headset
speaker
-
-
-
9
NC
-
-
Not connected, please
keep this pin open
-
-
-
10
INTMIC_N
-
AI
Negative pole of the
input of handset
microphone
-
-
-
11 NC
-
-
N- ot con
nected,
-
-
12
INTMIC_P
-
AI
Positive pole of the
input of handset
microphone
-
-
-
13
NC
-
-
Not connected, please
keep this pin open
-
-
-
14
EXTMIC_P
-
AI
Positive pole of the
input of headset
microphone
-
-
-
15
NC
-
-
Not connected, please
keep this pin open
-
-
-
16
EXTMIC_N
-
AI
Negative pole of the
input of headset
microphone
-
-
-
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HUAWEI MG301 B2B Module
HardwareGuide Description of the Application Interfaces
Pin
No.
Pin Name
I/O
Description
DC Characteristics (V)
Normal
MUX
Min.
Tpy.
Max
17
NC
-
-
Not connected, please
keep this pin open
-
-
-
18
GND
-
-
Ground
-
-
-
19
NC
-
-
Not connected, please
keep this pin open
-
-
-
20
TERM_ON
-
I
Power on/power off
control
-
internal
pulled up
-
21
NC
-
-
Not connected, please
keep this pin open
-
-
-
22
RESET
-
I
Hardware reset
–0.40
2.80
3.20
23
NC
-
-
Not connected, please
keep this pin open
-
-
-
24
UART1_DCD
-
O
DCE data carrier detect
–0.40
2.80
3.20
25
LED_STATUS
-
O
Network status
indication
–0.40
2.80
3.20
26
NC
-
-
Not connected, please
keep this pin open
-
-
-
27
NC
-
-
Not connected, please
keep this pin open
-
-
-
28
UART1_CTS
-
O
DCE clear to send
–0.40
2.85
3.25
29
UART1_RD
-
O
DCE transmit data
–0.40
2.85
3.25
30
NC
-
-
Not connected, please
keep this pin open
-
-
-
31
NC
-
-
Not connected, please
keep this pin open
-
-
-
32
UART1_DTR
-
I
DCE data terminal
ready
–0.40
2.80
3.20
33
UART1_TD
-
I
DCE receive data
–0.40
2.80
3.20
34
UART1_RTS
-
I
DCE request to send
–0.40
2.85
3.25
35
VCOIN
-
P
Standby power input of
the RTC
2.00
3.00
3.15
36
UART1_DSR
-
O
DCE data set ready
–0.40
2.80
3.20
37
NC
-
-
Not connected, please
keep this pin open
-
-
-
38
UART1_RING
-
O
DCE ring indicator
–0.40
2.80
3.20
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HUAWEI MG301 B2B Module
HardwareGuide Description of the Application Interfaces
Pin
No.
Pin Name
I/O
Description
DC Characteristics (V)
Normal
MUX
Min.
Tpy.
Max
39
NC
-
-
Not connected, please
keep this pin open
-
-
-
40
VIO
-
P
External power output
2.70
2.80
2.95
41
GND
-
-
Ground
-
-
-
42
VBAT
-
P
Power supply input
3.30
3.80
4.80
43
GND
-
-
Ground
-
-
-
44
VBAT
-
P
Power supply input
3.30
3.80
4.80
45
GND
-
-
Ground
-
-
-
46
VBAT
-
P
Power supply input
3.30
3.80
4.80
47
GND
-
-
Ground
-
-
-
48
VBAT
-
P
Power supply input
3.30
3.80
4.80
49
GND
-
-
Ground
-
-
-
50
VBAT
-
P
Power supply input
3.30
3.80
4.80
P indicates power pins; I indicates pins for digital signal input; O indicates pins for digital
signal output; AI indicates pins for analog signal input; AO indicates pins for analog signal
input.
The NC (Not Connected) pins are internally connected to the module. Therefore, these pins
should not be used, otherwise they may cause problems. Please contact us for more
details about this information.
3.3 Power Interface
3.3.1 Overview
The power supply part of the B2B interface of the MG301 B2B module contains:
VBAT interface for the power supply
VCOIN interface for the standby power supply of the real-time clock (RTC)
VIO interface for external power output
Table 3-2 lists the definitions of the pins on the power supply interface.
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HUAWEI MG301 B2B Module
HardwareGuide Description of the Application Interfaces
Table 3-2 Definitions of the pins on the power supply interface
Pin No.
Signal Name
I/O
Description
42, 44, 46, 48, 50
VBAT
P
Pins for Power supply input
41, 43, 45, 47, 49
GND
-
GND
35
VCOIN
P
Pin for standby power input of
the RTC
40
VIO
P
Pin for external power output
3.3.2 VBAT Interface
When the MG301 B2B module works normally, power is supplied through the VBAT
pins and the voltage ranges from 3.3 V to 4.8 V (typical value: 3.8 V). The 50-pin B2B
connector provides five VBAT pins and five GND pins for external power input. To
ensure that the MG301 module works normally, all the pins must be used efficiently.
When the MG301 B2B module is used for different external applications, pay special
attention to the design for the power supply. When the MG301 B2B module transmits
signals at the maximum power, the transient current may reach the transient peak
value of about 2.0 A due to the differences in actual network environments. In this
case, the VBAT voltage greatly drops. Make sure that the voltage does not decrease
below 3.3 V in any case. Otherwise, exceptions such as restart of the MG301 B2B
module may occur.
A low-dropout (LDO) regulator or switch power with current output of more than 2 A is
recommended for external power supply. Furthermore, At least five 220 µF storage
capacitors should be connected in parallel at the power interface of the MG301 B2B
module. In addition, to reduce the impact of channel impedance on voltage drop, you
are recommended to try to shorten the power supply circuit of the VBAT interface.
It is recommended to employ a ferrite bead in series on VBAT power circuit to
improve the EMI performance. And the rated current of the ferrite bead is required at
least 2 A.
Figure 3-2 shows the recommended power circuit of MG301 B2B module.
Figure 3-2 Recommended power circuit of MG301 B2B module
Module
(DCE)
VBAT
VBAT
+ + + + +
10 μF
100 nF 220 μF
220 μF 220 μF 220 μF 220 μF
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HUAWEI MG301 B2B Module
HardwareGuide Description of the Application Interfaces
3.3.3 VCOIN Interface
VCOIN is an interface for standby power input of the RTC in the MG301 B2B module.
If the VBAT interface is ready for power supply, it on priority supplies the RTC with
power. If the VBAT interface is not ready, the VCOIN interface provides standby
power input for the RTC. In this case, the MG301 B2B module needs 5 µA to maintain
the RTC function.
You can use an external battery to supply power through the VCOIN interface. The
recommended voltage is 3 V. You can also use an external capacitor if you do not
use a battery. The capacitance determines the duration of the RTC when the VBAT
interface is not ready.
The MG301 B2B module supports charging external standby batteries. When the
VBAT voltage is 3.8 V, the charging current is about 0.6 mA (typical value). Figure 3-3
shows two types of circuits for your reference.
Figure 3-3 VCOIN interface circuit
3.3.4 VIO Interface
Through the VIO interface, the MG301 B2B module can supply 2.8 V power externally
with an output current of 10 mA (typical value) for external level conversion or other
applications.
If the MG301 B2B module is in sleep mode, the VIO interface is in the low power
consumption state (< 500 µA ). If the MG301 B2B module is in power down mode, the
VIO is in the disabled state. If VIO pin is not in use, disconnect the pin and make sure
it is not grounded.
3.4 Power-On and Power-Off Time Sequence
3.4.1 Overview
The power-on, power-off, and reset control parts of the B2B interface of the MG301
B2B module includes power-on/power-off interface signal (TERM_ON) and the
hardware reset interface signal (RESET). Table 3-3 lists the definitions of the
interface pins.
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HardwareGuide Description of the Application Interfaces
Table 3-3 Definitions of pins of the power-on/power-off and reset interfaces
Pin No.
Signal Name
I/O
Description
20
TERM_ON
I
Pin for controlling power-on and power-off
22
RESET
I
Pin for resetting the hardware
3.4.2 Power-On Time Sequence
Make sure that the MG301 B2B module is powered on at the voltage and operating
temperature in the recommended range. Otherwise, the module may get
damaged or work improperly.
External application interfaces must be powered on after the module is powered
on.
You can power on the MG301 B2B module through the TERM_ON interface. The
software will report relevant information according to the actual settings after the module
is powered on. For example, the AT command automatically reports ^SYSSTART[1]. In
this case, the external VIO interface is enabled and supplies 2.8 V power.
[1] For specific setting information about the power-on/power-off software, see the HUAWEI
MG301 Series Wireless Module AT Command Interface Specification.
Figure 3-4 shows the power-on time sequence.
Figure 3-4 Power-on time sequence
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HUAWEI MG30 B2B Module
HardwareGuide Description of the Application Interfaces

Fetch Ext Code in the figure is a file system in the MG301 B2B module.

Before powering on the MG301 B2B , make sure that TERM_ON is in High-Z condition.
3.4.3 Power-Off Time Sequence
The MG301 B2B module supports power-off through the TERM_ON interface or the
AT^SMSO command. Figure 3-5 shows the power-off time sequence.
Figure 3-5 Power-off time sequence
The processing of the power-off event depends on the normal stop time of the file system
in the MG301 B2B module. The processing varies with the capacity of the file system.
Do not suddenly turn off the VBAT power when the module is working. It is recommended
to power-off the module before turning off the VBAT power.
3.4.4 RESET
The MG301 B2B module supports hardware reset function. If the software of the
MG301 B2B module stops responding, you can reset the hardware through the
RESET signal. After the hardware is reset, the software starts powering on the
module and reports relevant information according to the actual settings. For
example, the AT command automatically reports ^SYSSTART. In this case, the
external VIO interface is enabled and supplies 2.8 V power.
3.5 Signal Control Interface
3.5.1 Overview
The signal control part of the B2B interface in the MG301 B2B module consists of:
Power-on/off (TERM_ON) pin
Hardware reset (RESET) pin
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Network status LED (LED_STATUS) pin
Table 3-4 lists the pins on the signal control interface.
Table 3-4 Pins on the signal control interface
Pin No.
Signal Name
I/O
Description
20
TERM_ON
I
Pin for controlling power-on and power-off
22
RESET
I
Pin for resetting the hardware
25
LED_STATUS
O
Pin for network status LED
3.5.2 Input Signal Control Pins
The MG301 B2B module implements power-on and power-off and resets the hardware
through the input signal control pins.
The TERM_ON pin is used to implement power-on and power-off. If the TERM_ON
pin is pulled down for 1 second to 2 seconds, the module is powered on; if the
TERM_ON pin is pulled down for 1 second to 2 seconds again, the module is
powered off.
The RESET pin is used to reset the hardware. When the software stops responding,
the RESET pin can be pulled down for at least 10 ms to reset the hardware.
As the RESET and TERM_ON signals are relatively sensitive, it is recommended that
you install a 10 nF capacitor near the RESET and TERM_ON pins of the B2B
interface for filtering. In addition, when you design a circuit on the PCB of the
interface board, it is recommended that the circuit length not exceed 20 mm and that
the circuit be kept at a distance of 2.54 mm (100 mil) at least from the PCB edge.
Furthermore, you need to wrap the area adjacent to the signal wire with a ground wire.
Otherwise, the module may be reset due to interference.
Figure 3-6 shows the connections of the TERM_ON and RESET pins.
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HUAWEI MG301 B2B Module
HardwareGuide Description of the Application Interfaces
Figure 3-6 Connections of the TERM_ON and RESET pins
RESET
HUAWEI Module
(Modem)
TERM_ON
10 nF
10 nF
c b 2.2 kΩ
e
c 2.2 kΩ
b
e
Application Device
(Host）
3.5.3 Output Signal Control Pin
The MG301 B2B module provides a network status LED pin LED_STATUS. The pulse
signal output through this pin controls the status LED on the user interface board to
display the network status.
Different blinking modes of the status LED indicate different network status. Table 3-5
describes the status of the LED_STATUS pin.
Table 3-5 Status of the LED_STATUS pin
Working or Network Status
Output Status of the LED_STATUS Pin
Sleep mode
A low-level signal is output continuously.
Network-searching or non-network
status (including the case when the
SIM card is not inserted and the case
when the PIN number is unblocked)
A high-level signal is output for 0.1s in a
period of 1s.
Registered with a 2G network
A high-level signal is output for 0.1s in a
period of 3s.
GPRS data service
A high-level signal is output for 0.1s in a
period of 0.125s.
Voice call
A high-level signal is output
continuously.
In practical application, the LED_STATUS pin cannot be directly used to drive the
status LED. The LED_STATUS pin needs to be used with a triode. To select a
suitable current-limiting resistor for the LED, check the actual voltage drop and rated
current of the LED. Figure 3-7 shows the driving circuit.
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HUAWEI MG301 B2B Module
HardwareGuide Description of the Application Interfaces
Figure 3-7 Driving circuit
3.6 UART Interface
3.6.1 Overview
The MG301 B2B module provides the UART1 (8-wire UART) interface for one
asynchronous communication channel. As the UART1 interface supports signal
control through standard modem handshake, AT commands are entered and serial
communication is performed through the UART1 interface. The UART1 has the
following features:
Full-duplex
Baud rate clock generated by the system clock
Direct memory access (DMA) transmission
Baud rate ranging from 9600 bit/s to 230400 bit/s (115200 bit/s by default)
Self-adapted baud rate ranging from 9600 bit/s to 115200 bit/s
Table 3-6 lists the UART1 interface signals.
Table 3-6 UART1 interface signals
Pin No.
Signal Name
Description
Feature
Direction
29
UART1_RD
DCE transmit
data
The data terminal
equipment (DTE)
receives serial
data.
Data circuit-
terminating
equipment
(DCE) to DTE
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Issue 06 (2013-06-13)