MG815+ Module Hardware Design User Manual

MG815+ Module Hardware Design User Manual
MG815+ Module Hardware Design User Manual
Version˖V1.4
ZTE Corporation
This manual is also applicable for ME3000/ME3006/MG615+/MG415+/MG416+ modules.
MG815+ Module Hardware Design User Manual
Preface
Summary
This manual is applicable for ME3000/ME3006/MG815+/MG615+/MG415+/MG416+ modules. This manual
takes MG815+ and ME3000 as examples to instruct the users how to design the hardware and how to quickly
and conveniently design different kinds of wireless terminals based on the modules.
Target Readers
System designing engineers
Mechanical engineers
Hardware engineers
Software engineers
Test engineers
Brief Introduction
Chapter
Contents
1 General Description
Introduces technical specs of the modules and relevant documents and
abbreviations.
2 Product Introduction to
MG815+
Introduces the principle charts and relevant standards of both MG815+ and
ME3000 modules.
3 PIN Definitions
Introduces the name and function of PIN.
4 Hardware Interfaces and
design reference
Introduces the hardware interface designing of the modules.
5 Mechanical
Introduces the module’s appearance, assembly line, main board PCB layout
and fixing.
6 Peripherals components
Introduces the peripherals components.
Update History
V1.4 ˄June-25-2007˅
This is the fifth time to release the new version. The update contents include:
1.1.4 Modifications in Technical parameters
1.2 Modifications in Relevant Documents
4.2 Power and Reset Add ON/OFF timing
5.1 Change the modules weight a more accurate value.
V1.3 ˄May-31-2007˅
This is the fourth time to release the new version. The update contents include:
4.2 Modifications in Section Power and Reset
4.4 Change user ID card interface to SIM/UIM card interface
4.5 Audio Interface: Deleted x05ˈx06ˈx07 in the picture, and just kept receiver, handset, and line out.
Change CDMA and GSM audio interface design
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MG815+ Module Hardware Design User Manual
4.6 Change RF interface as antenna interface.
5.1 Appearance: Add ME3000’s appearance.
5.3 Change PCB Layout.
6 Change Key components as peripherals.
V1.2 (April-24-2007)
This is the third time to release the version. The update contents include:
6.4 Audio Interface
Add Auto power-on/off, audio interface design
V1.1 ˄April-13-2007˅
The update contents include:
5 PIN definitions
Change fig5-1 PIN Diagram
6 Hardware Interface and Reference Design
Change R12 impedance in Fig6-1 as 1K
6.4 Audio Interface
Add the design of audio interface
Add section 6.6 Module Layout
V1.0 ˄Feb-09-2007˅
This is the first to formally release the document.
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MG815+ Module Hardware Design User Manual
Table of Contents
1
2
3
4
5
6
General Description........................................................................................................................................ 8
1.1 Technical Specification......................................................................................................................... 8
1.1.1
Module Specification.............................................................................................................. 8
1.1.2
Main Functions and Features.................................................................................................. 8
1.1.3
Interfaces ................................................................................................................................ 9
1.1.4
Technical parameters .............................................................................................................. 9
1.2 Relevant Documents........................................................................................................................... 10
1.3 Abbreviations ..................................................................................................................................... 10
Brief Introduction to MG815+ ..................................................................................................................... 12
2.1 Brief Introduction to MG815+ ........................................................................................................... 12
2.2 Brief Introduction to ME3000 ............................................................................................................ 12
PIN definitions.............................................................................................................................................. 14
Hardware Interfaces and Design Reference ................................................................................................. 18
4.1 Summary............................................................................................................................................. 18
4.2 Power and Reset ................................................................................................................................. 18
4.3 Serial Port ........................................................................................................................................... 19
4.4 SIM/UIM Card Interface .................................................................................................................... 21
4.5 Audio Interface................................................................................................................................... 21
4.6 Antenna Interface ............................................................................................................................... 23
Mechanical ................................................................................................................................................... 24
5.1 Appearance ......................................................................................................................................... 24
5.2 Module Assembly Line....................................................................................................................... 25
5.3 Main board PCB layout ...................................................................................................................... 25
5.4 Fixing Method .................................................................................................................................... 26
Peripherals components................................................................................................................................ 27
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MG815+ Module Hardware Design User Manual
Table of figures
FIGURE 2-1 MG815+ PRINCIPLE....................................................................................................................................12
FIGURE 2-2 ME3000 PRINCIPLE ....................................................................................................................................12
FIGURE 3-1 PIN.............................................................................................................................................................14
FIGURE 4-1 POWER AND RESET CIRCUIT DESIGN REFERENCE .........................................................................................18
FIGURE 4-2 ON/OFF TIMING .........................................................................................................................................19
FIGURE 4-3 UART TO MCU INTERFACE ........................................................................................................................20
FIGURE 4-4 UART 1 SIGNAL DIAGRAM ........................................................................................................................20
FIGURE 4-5 SIM/UIM CARD INTERFACE DESIGN REFERENCE ........................................................................................21
FIGURE 4-6 AUDIO INTERFACE CIRCUIT DESIGN REFERENCE ..........................................................................................22
FIGURE 4-7 ANTENNA INTERFACE .................................................................................................................................23
FIGURE 4-8 RF CABLE INTERFACE .................................................................................................................................24
FIGURE 5-1 MODULE APPEARANCE OF MG815+............................................................................................................24
FIGURE 5-2 MODULE APPEARANCE OF ME3000 ............................................................................................................25
FIGURE 5-3 MODULE ASSEMBLY LINE˄BOTTOM VIEW˅ .............................................................................................25
FIGURE 5-4 MAIN BOARD PCB LAYOUT˄TOP VIEW˅ ..................................................................................................25
FIGURE 5-5 FIXING METHOD ..........................................................................................................................................26
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MG815+ Module Hardware Design User Manual
Tables
TABLE 1-1 MODULE SPECIFICATION .................................................................................................................................8
TABLE 1-2 MAIN FUNCTIONS AND FEATURES ...................................................................................................................8
TABLE 1-3 INTERFACES OF THE MODULES .......................................................................................................................9
TABLE 1-4 TECHNICAL PARAMETERS OF MC8530 ...........................................................................................................9
TABLE 3-1 PIN DEFINITIONS OF 40 PIN CONNECTOR .....................................................................................................14
TABLE 3-2 PIN DEFINITIONS OF 10 PIN CONNECTOR .....................................................................................................16
TABLE 4-1 VOLTAGE FEATURES .....................................................................................................................................18
TABLE 4-2 ON/OFF TIMING FEATURES ..........................................................................................................................19
TABLE 4-3 USB AND UART-2 PIN SN AND NAME........................................................................................................20
TABLE 6-1 PERIPHERALS COMPONENTS .........................................................................................................................27
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MG815+ Module Hardware Design User Manual
1 General Description
This manual is applicable for ME3000/ME3006/MG815+/MG615+/MG415+/MG416+ modules. Except for
antenna design, the hardware/mechanical design is completely compatible with the applications of CDMA
800M, Sec800MHz, 450M and GSM/GPRS. All above modules have voice, SMS and data service function,
which could be used for data transmission, wireless POS, security, lottery, intelligent metering, wireless fax,
small exchangers, tobacco network, campus network, wireless AD, wireless media, medical surveillance,
relay station surveillance, railway terminal, intelligent home appliances, vehicle-mounted surveillance, etc.
Taking MG815+ and ME3000 module as examples, this manual describes the module’s logic structure,
hardware interface and main functions, and provides reference design for the hardware and mechanics.
1.1 Technical Specification
1.1.1 Module Specification
Please refer to table 1-1 for the specifications of 5 types of modules ME3000, MG815+, MG615+, MG415+
and MG416+.
Table 1-1 module specification
Frequency(MHz)
Module Models
Standard
ME3000
GSM/GPRS
Quad Band: GSM 850/EGSM 900/DCS 1800/PCS 1900
MG815+
CDMA 2000 1X
800MHz
MG615+
CDMA 2000 1X
Sec800MHz
MG415+
CDMA 2000 1X
450MHz block A
MG416+
CDMA 2000 1X
450MHz block C
Remarks: The modules are compatible on hardware and mechanical design except for frequency. Below is
just an example for MG815+ and ME3000 modules.
1.1.2 Main Functions and Features
Please refer to Table 1-2 for the Main Functions and Features.
Table 1-2 Main functions and features
Item
Description
CDMA
GSM
Voice
EVRC and 13kQCELP High-quality voice
SMS
Support TEXT
Data
! Support internal TCP/IP stack
! Support virtual keep on-line(VKL)
CDMA maximum up/down link data rate 153.6kbps; GSM maximum up-link
data rate 42.8kbps, maximum down-link data rate 85.6kbps.
Support TEXT and PDU
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MG815+ Module Hardware Design User Manual
1.1.3 Interfaces
Please refer to Table 1-3 for the Interfaces.
Table 1-3 Interfaces of the modules
Item
Description
CDMA
GSM
UART interface
Download software to update
Data communication
Maximum data rate 230.4kbps through the port
Audio interface
Double audio I/O channel.
UIM card interface
Built-in UIM/R-UIM
Antenna interface
50 Ohm input impedance control
RTC
none
UIM card interface
RTC
1.1.4 Technical parameters
Please refer to Table 1-4 for the Technical parameters of MC8530.
Table 1-4 Technical parameters of MC8530
Item
Description
CDMA
GSM
Working temperature
-30°C ~ +75°C
-20°C ~ +80°C
Input voltage
3.3V-4.25V
Maximum current
560mA @ -104 dBm
500mA @ -102 dBm
Idle current
5mA @ -75 dBm
10mA @ -75 dBm
Call current
230mA @ -75 dBm
150mA @ -75 dBm
sensitivity
104 dBm
102dBm
Tx power
23dBm ~ 30dBm (Class III)
GSM850,EGSM900:Class4(2W)
GSM1800, PCS1900:Class1(1W)
GSM850
Frequency
range
800MHz
Tx˖824~849 MHz
Rx˖869~894 MHz
Tx˖824~849 MHz
Rx˖869~894MHz
Sec800MHz
Tx˖806~821 MHz
Rx˖851~DL866 MHz
EGSM900
Tx˖880~915 MHz
Rx˖925~960MHz
450MHz A ↉
Tx˖450~460 MHz
Rx˖460~470 MHz
Preferred channel˖160ˈ210ˈ260
DCS1800
Tx˖1710~1785MHz
Rx 1805~1880MHz
450MHz C ↉
Tx˖450~460 MHz
Rx˖460~470 MHz
Preferred channel˖47ˈ97ˈ147
PCS1900
Tx˖1850~1910MHz
Rx˖1930~1990MHz
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MG815+ Module Hardware Design User Manual
1.2 Relevant Documents
ljZTE Dragon tooth wireless module series product catalogNJ
ljAT Command Manual for ZTE Corporation's MG815+ ModulesNJ
ljAT Command Manual for ZTE Corporation's ME3000 ModulesNJ
ljZTE MG815+ Module Development Board User GuideNJ
ljFAQ for ZTE Corporation's CDMA ModulesNJ
ljFAQ for ZTE Corporation's GSM/GPRS ModulesNJ
ljTest References of ZTE Corporation's CDMA Wireless ModulesNJ
1.3 Abbreviations
Abbr.
ADC
Full name
Analog-Digital Converter
AFC
Automatic Frequency Control
AGC
Automatic Gain Control
ARFCN
Absolute Radio Frequency Channel Number
ARP
Antenna Reference Point
ASIC
Application Specific Integrated Circuit
BER
Bit Error Rate
BTS
Base Transceiver Station
CDMA
Code Division Multiple Access
CDG
CDMA Development Group
CS
Coding Scheme
CSD
Circuit Switched Data
CPU
Central Processing Unit
DAI
Digital Audio interface
DAC
Digital-to-Analog Converter
DCE
Data Communication Equipment
DSP
Digital Signal Processor
DTE
Data Terminal Equipment
DTMF
Dual Tone Multi-Frequency
DTR
Data Terminal Ready
EFR
Enhanced Full Rate
EGSM
Enhanced GSM
EMC
Electromagnetic Compatibility
EMI
Electro Magnetic Interference
ESD
Electronic Static Discharge
ETS
European Telecommunication Standard
FDMA
Frequency Division Multiple Access
FR
Full Rate
GPRS
General Packet Radio Service
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MG815+ Module Hardware Design User Manual
GSM
Global Standard for Mobile Communications
HR
Half Rate
IC
Integrated Circuit
IMEI
International Mobile Equipment Identity
ISO
International Standards Organization
ITU
International Telecommunications Union
LCD
Liquid Crystal Display
LED
Light Emitting Diode
MCU
Machine Control Unit
MMI
Man Machine Interface
MS
Mobile Station
PCB
Printed Circuit Board
PCL
Power Control Level
PCS
Personal Communication System
PDU
Protocol Data Unit
PLL
Phase Locked Loop
PPP
Point-to-point protocol
RAM
Random Access Memory
RF
Radio Frequency
ROM
Read-only Memory
RMS
Root Mean Square
RTC
Real Time Clock
SIM
Subscriber Identification Module
SMS
Short Message Service
SRAM
Static Random Access Memory
TA
Terminal adapter
TDMA
Time Division Multiple Access
TE
Terminal Equipment also referred it as DTE
UART
Universal asynchronous receiver-transmitter
UIM
User Identifier Management
USB
Universal Serial Bus
VSWR
Voltage Standing Wave Ratio
ZTE
ZTE Corporation
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MG815+ Module Hardware Design User Manual
2 Brief Introduction to MG815+
2.1 Brief Introduction to MG815+
Please refer to Figure 2-1 for the Technical parameters of MG815+.
Figure 2-1 MG815+ principle
2.2 Brief Introduction to ME3000
Please refer to Figure 2-2 for the Technical parameters of ME3000.
Figure 2-2 ME3000 principle
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MG815+ Module Hardware Design User Manual
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MG815+ Module Hardware Design User Manual
3 PIN definitions
The main connector of MG815+ or ME3000 is 40-PIN connector and 10-PIN connector. The distance between
two PINS is 1.27mm. Refer to the figure below:
Figure 3-1 PIN
Refer to table 3-1/3-2 below for PIN definitions:
Table 3-1 PIN definitions of 40 PIN connector
Function Pin No. Signal name
I/O
Basic functions
Remarks
MIC_1P
I
MIC
1
Anode
39
Audio
Serial
port 1
37
MIC_1N
I
MIC 1 Cathode
34
SPK_1P
O
Receiver 1 Anode
32
SPK_1N
O
40
MIC_2P
I
Receiver 1 Cathode
MIC 2 Anode
38
MIC_2N
I
MIC 2 Cathode
33
SPK_2P
O
Receiver 2 Anode
35
EAR_AN_DE
T
I
36
EAR_DET
I
Earphone inserting test
27
AUXOP
O
Line output, anode
29
AUXON
O
Line output, Cathode
12
/CTS
O
Clear to send
low level valid.
14
/RTS
I
Request to send
low level valid
13
TXD
O
Transmit data
11
RXD
I
Receive data
15
RI
O
Ring indicating signal
Earphone button test
14
MIC 1 is the default
configuration for audio I/O
when power on, generally
MIC 1 is used for handset,
MIC 2 for earphone
draw up internalˈlow level
valid
draw down internalˈ low
level valid
TTL level.
1. high level when
MG815+ Module Hardware Design User Manual
17
/DSR
O
Module is ready
18
DCD
/DTR
O
Carrier signal testing
I
User circuit is ready
16
UIM
card
interface
Serial
port 2 or
USB
interface
4
CARD_DAT
A
I/O
Data cable
6
CARD_CLK
O
8
V_CARD
O
Clock wire
3V power output
2
CARD_RST
O
Reset wire
PIN
number
Signal name
USB
UAR
T
USB
1
USB_
OE/TXD2
O
O
To USB
Transceiver
3
USB_DATA/
RXD2
I
I
To
USB
Transceiver
5
USB_VMO/
RTS2
O
I
To
USB
Transceiver
7
USB_VPO/
CTS2
O
O
9
USB_SUS
O
NC
O
Call/message indicator
28
SMS_LED
To
USB
Transceiver
Suspend status
indicating
LED
30
SIG_LED
O
Signal indicator
15
initialized;
2. producing a periodic
signal(100ms low,5.9s
high) when received a
ring indicating signal;
3. Back to high level when
the ring indicating
signal is terminated.
low level valid
low level valid
UART
The
same to
serial
port 1
suspend
GSM module
supports UART but
not USB.CDMA
module supports both
UART and USB, but
software should be
changed with
different interface.
Pin 5 and pin 7 are
available at low level
within UART.
Draw down internal, LED
will be turned on at high
level(with external driver)
Draw down internal, LED
will be turned on at high
level (with external driver).
-Turn on: LED off
-Searching for network:
LED flashes, and it lasts for
about 50ms when it is on,
and the time is flexible when
it is off;
-Idle: LED blinks per
100ms.
--Traffic (call, data): LED
blinks per 500ms
MG815+ Module Hardware Design User Manual
26
ON/OFF
switch control
I
Reset
10
/RESET
I
Reset signal
19
V_MAIN
Power
input
Main power of module
21
V_MAIN
Power
input
Main power of module
22
V_MAIN
Power
input
Main power of module
23
GND
Ground
24
GND
Ground
power
25
V_MSM
power
output
Digital power
Draw up internalˈLow level
valid. For details, please
refer to section 4.2 Power
and Reset
Low level valid
Need to connect an open
collector or an open drain
switch. For details, please
refer to section 4.2 Power
and Reset
MG815+ module has a
voltage output pin with
current limited adjuster. It
can be used to supply
external circuit on main
board. the voltage of this
pin, baseband processor and
storage come from the same
voltage adjuster. voltage
output is 2.85V when power
on. Users should distribute
current as little as possible
from this pin(less than
10mA). Generally, we
suggest this pin is used to
pull up chips’ pin only when
it needs level match.
20
NC
Used for module inside,
need to be suspended
31
NC
Used for module inside,
need to be suspended
reserved
Table 3-2 PIN definitions of 10 PIN connector
Function
power
PIN No.
Signal Name
I/O
1
GND
GND
2
GND
GND
3
GND
GND
Basic functions
16
Remarks
MG815+ Module Hardware Design User Manual
reserved
4
GND
5
NC
6
NC
7
NC
8
NC
9
NC
0
NC
GND
Used for module inside, need to be
suspended
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MG815+ Module Hardware Design User Manual
4 Hardware Interfaces and Design Reference
4.1 Summary
This section describes the function interfaces and usage of MG815+ modules in details, and provides the
designing sample.
Power and Reset Interface
Serial Port
SIM/UIM Card Interface
Audio Interface
Antenna Interface
Remarks: In the system, the module layout should be far away from high-speed circuit, switch power, power
transformer, large power inductor, or single chip microcomputer’s clock circuit.
4.2 Power and Reset
Figure 4-1 power and reset circuit design reference
Power design
The module is powered by V-MAIN, and the voltage feature is below:
Table 4-1 Voltage features
Category
Min.
Typical
Max.
Input voltage
3.3 V
3.9 V
4.25 V
D1 is a LDO with low-valid control, making V_MAIN supplies power to module through adjusting R31and
R41 at 3.9V. Modules have very high requirements on power and ground processing, signals must be filtered.
Power ripple needs to be controlled under 50Mv. Do not supply power to any other part of system, otherwise
RF performance will be compromised. Finally, select the power cables with at least 40mil traces during the
layout and keep the integrality of ground line.
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MG815+ Module Hardware Design User Manual
Power ON
The module will be turned off after power-on normally. To turn on the module, firstly put /RESET at high level,
and then provide a 1500-2000mS low level pulse to ON/OFF PIN. /Reset needs to connect an open collector or
open drain gate.
Power OFF
To turn off the module, firstly provide a 1500-2000mS low level pulse to ON/OFF PIN, after 5s or 6s, and put
/RESET at low level.
Reset
You could turn off the module firstly and then turn it on to reset the module.
ON/OFF timing figure is as follows:
Figure 4-2 ON/OFF timing
Table 4-2 ON/OFF timing features
ta
20mS
tb
10mS
tc
2S
td
2S
te
6S
V_MSM
There is a voltage output pin with current adjuster, which can be used to supply external power to the board.
The voltage of this pin and the voltage of baseband processor/memory come from the same voltage adjuster.
The voltage output is available only when the module is on. The normal output voltage is 2.85V, and the user
should absorb the current from this pin as little as possible (less than 10mA). Generally, it is recommended to
use this pin to match the level. When the module is off, the output voltage for this pin remains unchanged, but
the impedance is rather high. Therefore, it’s not recommended to use this pin for other purposes.
Other Advice
In order to make sure the data is saved safely, please don’t cut off the power when the module is on. It’s
strongly recommended to add battery or soft switch like the power key on the mobile phone.
4.3 Serial Port
The module provides 2 UART transceivers and its logic functions conform to RS-232 interface standard. These
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MG815+ Module Hardware Design User Manual
two UART could be used as serial port data interfaces to transmit data, provide test and debug channel, and
download the software for upgrade.
Refer to Fig 4-3 when UART 1 is used as MCU:
Figure 4-3 UART to MCU interface
It is noted that the interface level of UART provided by the module shall conform to CMOS level, while not
meet the requirements specified by RS-232 interface standard. If it is required to connect with the devices
through standard RS-232 interface during the applications, second development designers must add transfer
chip into their own designing, and use UART pins according to CMOS interface designing requirements. It’s
recommended to use 3V for UART level. MCU_BUT is the reset button.
It’s specially noted that users need to extend UART 1 or UART 2 to update software, if they’d like to connect
module to DTE in the design phase.
Refer to Fig 4-4 for UART 1 signal diagram:
Figure 4-4 UART 1 Signal Diagram
The corresponding PINS of UART 2 are for both UART and USB. GSM modules support UADT, but not USB;
while CDMA modules support USB and UART both. Please refer to table 4-3 for details.
Table 4-3 USB and UART-2 Pin SN and Name
Signal name
UART
USB
pin
USB_ OE/TXD2
TXD2
USB_ OE
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MG815+ Module Hardware Design User Manual
USB_DATA/RXD2
RXD2
USB_DATA
3
USB_VMO/ RTS2
RTS2
USB_VMO
5
USB_VPO/ CTS2
CTS2
USB_VPO
7
USB_SUS
9
USB_SUS
4.4 SIM/UIM Card Interface
Modules support 3V SIM/UIM card, SIM/UIM terminal includes 4 pins. V_CARD is used to supply SIM/UIM
card. It’s strongly recommended to add ESD to protect SIM/UIM card in hostile environments. D2 in the
following layout is for ESD:
Figure 4-5 SIM/UIM card interface design reference
NOTE: A 10k resistor is required for CARD_DATA pin to be draw up to V_CARD pin, because there are
different SIM/UIM cards with quite different output currents. SIM/UIM card PCB circuit should be laid closely
around the module as possible as you can, to avoid the interference of reading/writing from other sources.
4.5 Audio Interface
The module provides audio input and output through MIC_2P. There are 2 speaker interfaces, 2 microphone
interfaces and 1 line output. Only one pair I/O works at the same time.
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MG815+ Module Hardware Design User Manual
Figure 4-6 audio interface circuit design reference
Microphone
The system connector provides two microphone interfaces MIC_1 and MIC_2, which are both differential
interface. They could be also used as single ended input (for example: earphone). It’s recommended to use
differential mode to reduce the noises. These two input are coupled in AC domain and added a 1.8V offset
voltage inside, and they should directly connect with the receiver.
Speaker
The system connector provides two speakers, SPK_1 & SPK_2. The former is differential interface, and the
latter is single-ended interface, usually used for earphone. They both have 32 ohm impedance.
Line output
The MIC_2P connector provides a differential line output via AUXOP and AOXON. The impedance is 8 ohm.
CDMA module audio interface is designed as below:
Design of audio interface on the handset
Select the microphone with the sensitivity lower than -52dB since the output power for SPK_1 is 35mW and
the max. gain in MIC_1 reaches 52dB. The level of MIC_1P PIN is about 1.8V.
Note: if other kind of audio input method is adopted, the input signal should be within 2V. If the signal voltage
is lower than 2V, then the pre-amplifier should be added. If the signal voltage is higher than 2V, then network
attenuation should be added.
Design of audio interface on the receiver
Select the microphone with the sensitivity lower than -52dB since the output power for SPK_2 is 8.8mW and
the max. gain in MIC_2 reaches 52dB. The level of MIC_2P PIN is about 1.8V. The receiver’s design is just the
same as the handset’s.
GSM/GPRS module audio interface is designed as below:
Design of audio interface on the receiver
Select the microphone with the sensitivity lower than -51.5dB since the output impedance for SPK_1 is 32 ohm
and the max. gain in MIC_1 reaches 51.5dB. The level of MIC_1P PIN is about 2.5V.
Note: if other kind of audio input method is adopted, the input signal should be within 0.5V. If the signal
voltage is lower than 0.5V, then the pre-amplifier should be added. If the signal voltage is higher than 0.5V,
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MG815+ Module Hardware Design User Manual
then network attenuation should be added.
Design of audio interface on the earphone
Select the microphone with the sensitivity lower than -51.5dB since the output impedance for SPK_2 is 32 ohm
and the max. gain in MIC_2 reaches 51.5dB. The level of MIC_2P PIN is about 2.5V. The receiver’s design is
just the same as the handset’s.
4.6 Antenna Interface
The module provides two types of RF connector:
Extended jointing connector
RF testing socket
PCB jointing connector is used to connect module with antenna by 50 ohm RF shielding cable to cut down the
cost. But it’s not a complete way to shield EMI, and RF signal quality may be trivially affected. So if you
decide to use this method, intense radiation must keep far away from PCB jointing connector. At the same time,
you must ensure that core line of RF shielding cable has been jointed to PCB jointing connector, and the
shielding metal wire netting on the RF cable has been jointed to GND of module. According to the figure below,
the grounding part must be jointed firmly, otherwise, the core cable may be ruptured caused by shielding cable
shaking.
Figure 4-7 Antenna Interface
Antenna test socket is used for calibration and testing. It connects module with antenna conveniently by
appropriative 50 ohm socket to SMA connecting cable. The touch impedance of this socket is so tiny, and
shielding characteristics are excellent. The impedance of antenna test socket is 50 ohm, its type is
MM9329-2700B, please refer to socket manual provided by supplier to choose relative plugs. This is the
antenna cable interface:
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MG815+ Module Hardware Design User Manual
Figure 4-8 RF cable interface
Proper measures should be taken to reduce the access loss of effective bands, and good shielding should be
established between external antenna and RF connector. Besides, external RF cables should be kept far away
from all interference sources such as high-speed digital signal or switch power supply.
According to mobile station standard, stationary wave ratio of antenna should be between1.1 to 1.5, and input
impedance is 50 ohm. Different environments may have different requirements on the antenna’s gain. Generally,
the larger gain in the band and smaller outside the band, the better performance the antenna has. Isolation
degree among ports must more than 30dB when multi-ports antenna is used. For example, between two
different polarized ports on dual-polarized antenna, two different frequency ports on dual-frequency antenna, or
among four ports on dual-polarized dual-frequency antenna, isolation degree should be more than 30dB.
5 Mechanical
5.1 Appearance
Figure 5-1 module appearance of MG815+
Dimensions: 44.0 mm˄length˅x 28.0mm˄width˅x 7.6mm˄height˅
Weight: 8.5g
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MG815+ Module Hardware Design User Manual
Figure 5-2 module appearance of ME3000
Dimensions: 44.0 mm˄length˅x 28.0mm˄width˅x 7.6mm˄height˅
Weight: 8g
5.2 Module Assembly Line
Figure 5-3 Module assembly line˄bottom view˅
5.3 Main board PCB layout
Figure 5-4 main board PCB layout˄top view˅
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MG815+ Module Hardware Design User Manual
5.4 Fixing Method
The fixing metal sheet is made of stainless steelˈand there are two fixing methods: jointing or inserting bolt.
Refer to Fig 5-5 for product specification:
Figure 5-5 fixing method
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MG815+ Module Hardware Design User Manual
6 Peripherals components
Table 6-1 Peripherals components
Models
SN
Supplier
Website
MIC29302WU
D1
MICREL
www.micrel.com
UCLAMP0504A.TCT//
NZQA5V6XV5T1G
D2
SEMTECH//
ON
www.semtech.com
www.onsemi.com
IDT74FCT3244Q8//
PI74FCT3244Q
D3
PERICOM//
IDT
www.pericom.com
www.idt.com
SQPOFZ-40-S1-VB-0
X01
stwxe
www.stwxe.com.cn
QPOFY-10S1-VB-024
X02
stwxe
www.stwxe.com.cn
M-C707 10M006 097 2
X03
AMPHENOL
www.amphenol.com
27