LG LG-A120 User manual

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LG-A120
Service Manual
LG Electronics

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Table Of Contents
1. INTRODUCTION…………………...3
1.1 Purpose…………………………………3
1.2 Regulatory Information………………..3
2. PERFORMANCE…………………..5
2.1 H/W Features…………………………..5
2.2 S/W Features…………………………..6
3. TECHNICAL BRIEF………………14
3.1 Digital Main Processor( MT6223 )……….14
3.2 Power Amplifier Module( SKY77542 )…....22
3.3 Transceiver Module( AD6548 )…………..23
3.4 Memory Module ( K5L6443ABM-AD11) ….....26
3.5 FM Radio Module ( AR1200/1210 )…….….30
3.6 LCD Interface………………………....32
3.7 SIM Card Interface…..……………….34
3.8 KEYPAD Interface……………….…...35
3.9 Battery Charging Block Interface…...36
3.10 Audio Interface……………….….…..37
3.11 Vibrator Interface….………………...38
3.12 Key LED Interface……………….….39
4. TROUBLE SHOOTING…………..40
4.1 Power On Trouble……………………40
4.2 SIM Card Trouble…………………….43
4.3 Vibrator Trouble………………………45
4.4 Keypad Trouble……………………….47
4.5 RTC Trouble…………………………..50
4.6 Key Backlight Trouble………………..52
4.7 LCM Backlight Trouble…………….…55
4.8 LCM Trouble……………….……….…58
4.9 Microphone Trouble…………………..61
4.10 Receiver Trouble…………………….64
4.11 Speaker Trouble……………………..66
4.12 Headphone Trouble………….……...69
4.13 Charging Trouble…………………....73
4.14 Torch LED Trouble…………….75
4.15 FM Radio Trouble……………..77
4.16 No Connection Trouble……….80
4.17 RX Trouble…………………..…83
4.18 DCXO Trouble…………………86
4.19 SAW Filter Trouble……………87
4.20 TX Trouble……………………..88
4.21 Transceiver trouble……………90
4.22 PAM Trouble…………………...91
4.23 Mobile Switch Trouble………...96
5. DOWNLOAD………………....98
5.1 Download setup…………………98
5.2 Download Process……………...99
6. BLOCK DIAGRAM………….107
7. CIRCUIT DIAGRMA………...108
8. BGA IC PIN Check…………114
9. PCB LAYOUT……………….116
10.ENGINEERING MODE……118
11. CALIBRATION…………….122
11.1 Test Equipment Setup……….122
11.2 Calibration Steps……………..123
12. STAND ALONE TEST…….162
12.1 Test Configuration……………162
12.2 META tool Install process…...163
12.3 Rx Test………………………...166
12.4 Tx Test…………………………172
13. #EV#………………………...178

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1. INTRODUCTION
1.1Purpose
This manual provides information necessary to repair, description and download the features
of this model.
1.2 Regulatory Information
A. Security
Toll fraud, the unauthorized use of telecommunications system by an unauthorized part(for
example ,persons other than your company’s employees, agents, subcontractors, or person
working on your company’s behalf) can result in substantial additional charges for your
telecommunications services.
System users are responsible for the security of own system. There are may be risks of toll
fraud associated with your telecommunications system. System users are responsible for
programming and configuring the equipment to prevent unauthorized use .The manufacturer
dose not warrant that this product is immune from the above case but will prevent unauthorized
use of common-carrier telecommunications service of facilities accessed through or connected
to it.
The manufacturer will not be responsible for any charges that result from such unauthorized
use.
B. Incidence of Harm
If a telephone company determines that the equipment provided to customer is faulty and
possibly causing harm or interruption in service to the telephone network, it should disconnect
telephone service until repair can be done. A telephone company may temporarily disconnect
service as long as repair is not done.
C. Changes in Service
A local telephone company may make changes in its communications facilities or procedure. If
these changes could reasonably be expected to affect the use of the this phone or compatibility
with the network, the telephone company is required to give advanced written notice to the user,
allowing the user to take appropriate steps to maintain telephone service.
D. Maintenance Limitations
Maintenance limitations on this model must be performed only by the manufacturer or its
authorized agent . The user may not make any changes and/or repairs expect as specifically
noted in this manual.
Therefore, note that authorized alternations or repair may affect the regulatory status of the
system and may void any remaining warranty.

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E. Notice of Radiated Emissions
This model complies with rules regarding radiation and radio frequency emission as defined
by local regulatory agencies. In accordance with these agencies, you may be required to provide
information such as the following to the end user.
F. Pictures
The pictures in this manual are for illustrative purposes only; your actual hardware may look
slightly different.
G. Interference and Attenuation
Phone may interfere with sensitive laboratory equipment, medical equipment, etc.
Interference from unsuppressed engines or electric motors may cause problems.
H. Electrostatic Sensitive Devices
ATTENTION
Boards, which contain Electrostatic Sensitive Devices(ESD),are indicated by the
sign .
Following information is ESD handing:
. Service personnel should ground themselves by using a wrist strap when exchange system
boards.
.When repairs are made to a system board , they should spread the floor with anti-static mat
which is
also grounded .
.Use a suitable, grounded soldering iron .
. Keep sensitive parts in these protective packages until these are used.
.When returning system boards or parts like EEPROM to the factory, use the protective
packages as
described.

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2. PERFORMANCE
2.1 H/W Features
Solution 6223D MTK
Type Bar type
Antenna Type Internal (dual-Band)
Main Display 1.77” 128 x 160 , TFT/65k
Battery 950mAh Li-ion inner pack 950mAh: 55x34x5.7mm
Music player Yes Only for FM (AMR/WAV
file)
FM Receiver Yes , US/Europe band support (87.5~108MHz)
Embedded FM antenna Yes
Tension contact FPC
type FM Antenna on
Battery cover.
Real time FM recording Yes
Loud Speaker Yes x 2 ,
Φ 16 speaker
Music player--real resuming Yes
Memory Size 64Mb+32Mb User memory: 729KB
LMT (Lost Mobile Tracker) Yes LMT for: AMA
M-DOG: China
Torch LED Y
In flight mode Yes

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2.2 S/W Features
Feature Detail Item Description
OS OS Operating System Y
Speech Code FR,EFR,HR,AMR-NB Y
AMR code GSM Full Rate
3GPP Adaptive Multi Rate (AMR-NB)
Y
FM Radio Y
MP3 Ring
Tone
MP3 decode Y
Integrated hands
free
speaker
Speaker phone mode Y
Key Tone
Volume
6 Level (Include Mute) Y
Ring Tone
Volume
6 Level (Include Mute) Y
Ring Tone MP3 ring tone/Midi Y
Call Alert
type
Ring, Vibrate, Ring & Vibrate, Ring after
vibrate, Silent
Y
Earpiece
Volume
6 Level (Include Mute) Y
Audio
Mute Y
GSM dual
band MS
900-1800
Configuration is during software compile
time.
YFrequency
Bands
PCS dual
band MS
850-1900
N
Circuit NDate Service
Packet N
Infrared
(IrDA)
N
Bluetooth N
USB N
USB Mass
storage
N
Connectivity
RS232(UAR
T)
Only for manufacture tool Y

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Voice
Recording
Y
Voice
Command
N
Voice
Function
Answering
machine
N
Capture Size 160x120, 320x240, 640x480 N
Preview Size Full Screen: 128x128 N
Quality Low, Normal, High N
EV +4, +3, +2, +1, 0, -1, -2, -3, -4 N
WB Auto, Daylight, Tungsten,
FLUORESCENT, Cloud,
INCANDESCENCE
N
Zoom 640x480 : 1x
320x240 : 1x, 2x
160x120/128x128 : 1x, 2x, 4x
N
Effect Normal, Sepia, Grayscale, Color invert N
Continuous
Shot
1 Shot, 3 shot, 6 shot N
Self Timer 3 seconds, 5 seconds, 10 seconds N
Shutter tone Off, tone1, tone2, tone3 N
Storage Phone/SD card N
Camera
Reset Setting Restore to default setting N
Browse detail
image Info
NImage Viewer
Full Screen
View
N
Browse file
tree
Y
Copy,
Rename,
Delete, Move
files
Y
File Manager
(Sound folder)
Rename,
Delete,
Multi-Delete,
Create folder
Y
Display RSSI 6 level (0~5 level) Y

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Battery level 4 level (0~3 level) Y
RTC Date & Time Display Y
PLMN/Servic
e Indicator
Y
Quick Access
Mode In Idle
Y
Dimming
Clock
N
Dual Clock N
Home
shortcut
Display Shortcut icon in Idle(Quick
Access)
Y
Last Dial
Number
Max : 40 records Y
Last
Received
Number
Max : 40 records Y
Last Missed
Number
Max : 40 records Y
Scratch Pad
Memory
N
Call History
Call Duration Last Call time, Total Call Time Y
Last Call
Charge Units
YCall Cost
Total Charge
Units
Y
Call Waiting Y
Call Swap Y
Call Retrieve Y
Auto Answer N
Auto Redial Y
Calling Line N
Full Call
Divert
Y
Speed
Dialing
Y
Call
Management
Last Number
Redial
Y

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Multi Party
Call
Y
ECT Explicit Call Transfer Y
Automatic Network
Selection
Y
Manual
Network
Y
Preferred
Network
(User definition) Y
Network
Network
Service
Status
Y
DTMF
Signaling
YDTMF
DTMF
Enable &
Disable
Y
Read Cell
Broadcast
Y
On/Off
setting
Receive On/Off Y
Alert setting N
CB message
Language
setting
Y
Cell Broadcast
Channel
Setting
Y
Entry 1000 Y
Field Name, Mobile, Home, Office Y
Copy ME <-> SIM Y
Move ME <-> SIM Y
FDN Y
SDN Y
Email Entry N
Picture ID N
Video Caller
ID
N
Contacts(Pho
ne Book)
vCard N

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Business
Card
N
Delete Delete, Delete All(SIM or Phone), Multi
Delete
Y
CFU Call Forwarding Unconditional Y
CFB Call Forwarding on Mobile Subscriber
Busy
Y
CFNRy Call Forwarding on No Reply Y
CFNRc Call Forwarding on Mobile Subscriber
Not Reachable
Y
BAOC Barring of All Outgoing Calls Y
BOIC Barring of Outgoing International Calls Y
BOICexHC Barring of Outgoing International Calls
except those directed to the Home
PLMN Country
Y
BAIC Barring of All Incoming Calls Y
BICRoam Barring of Incoming Calls when
Roaming Outside the/Home PLMN
Country
Y
Supplementary
Services
Conference
Call
Up to 5 Y
Plug in Type 3V & 1.8 V Y
SIM Lock Service Provider / Network Lock N
SIM
SIM Toolkit Class 3 Y
Read
Message
Y
Write and
Edit Message
Y
Send and Receive
Message
Y
Reply to
Message
Y
Forward
Message
Y
Short
Message
Extract Number
from
Message
Y

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Message
Status
Y
Message
Unread
Y
Settable Message
Center Number,
Reply Path
and Validity
Y
Visible and Audible
Message
Receive
Y
Voice Mail Y
Settable Voice Mail
Center
Number
Y
Message
Protocol
Normal, Y
Message Overflow
Indicator
Blinking Icon Y
Message
Center
Number
Y
Nokia Smart
Message
N
Development &
Test
Facility
Y
Field Test
Facility
Y
Display
Software
Version
Y
IMEI Y
Miscellaneous
Function
Restore
Factory
Setting
Y

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Battery
Charging
Mode
Y
Language Selectable Auto Language YText Input
Predictive
word input
T9 Y
Calendar MAX: 100 records (35 chars) Y
To Do MAX: 50 records (35 chars) Y
Scheduler
Memo MAX: 10 records (80 chars) N
Setting Local
Time
Y
Display Two
Number of
Cities Time
Dual Clock N
Daylight
saving
Y
World Time
NITZ Y
Unit converter Length, Weight, Y
Stop Watch N
Calculator + - * / Y
Phone Book
Sync
Only For manufacture NPC Sync
Message
Sync
N
Game 2 C game Y
Emergency
Call
Y
Handset
Lock
Y
Security
Code
When Delete All N
PIN Lock Y
Security
Keypad Lock Y
12/24 Hour Y
Calendar Y
Time Zone Y
Real Time
Clock
Daylight
saving
N

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Alarm
Manager
Once, Daily, Mon~Fri, hourly Y
Dimming
Clock
N
Power-off
Alarm
Y
On Alarm
Event
Display & Ring Y
Mobile
Tracking
software
For India, Asia YOthers
M-DOG For China Y
Accessory Charger
Adapter
Y
Normal
earmic
(without hook
switch)
Y
User Memory 729 KB Y

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3.TECHNICAL BRIEF
3.1 Digital Main Processor
Figure.3-1-1 MT6223 FUNCTIONAL BLOCK DIAGRAM

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3.1.1 System Overview
MT6223D is an entry level chipset solution with class 12 GPRS/GSM modem. It integrates not
only analog baseband but also power management blocks into one chip and can greatly reduce the
component count and make smaller PCB size. Besides, MT6223D is capable of SAIC (Single
Antenna Interference Cancellation) and AMR speech.
Based on 32 bit ARM7EJ-STM RISC processor, MT6223D provides an unprecedented
platform for high quality Modem performance.
Platform
MT6223D runs the ARM7EJ-STM RISC processor at up to 52Mhz, thus providing best trade-off
between system performance and power consumption.
For large amount of data transfer, high performance DMA (Direct Memory Access) with
hardware flow control is implemented, which greatly enhances the data movement speed while
reducing MCU processing load.
Targeted as a modem-centric platform for mobile applications, MT6223D also provides hardware
security digital rights management for copyright protection. For further safeguarding, and to protect
manufacturer’s development investment, hardware flash content protection is also provided to
prevent unauthorized porting of software load.
Memory
MT6223D supports up to 2 external state-of-the-art devices through its 16-bit host interface.
Devices such as burst/page mode Flash, page mode SRAM, and Pseudo SRAM are supported. To
minimize power consumption and ensure low noise, this interface is designed for flexible I/O
voltage and allows lowering of supply voltage down to 1.8V. The driving strength is configurable for
signal integrity adjustment. The data bus also employs retention technology to prevent the bus
from floating during turn over.
Multi-media
MT6223D utilize high resolution audio DAC, digital audio, and audio synthesis technology to
provide superior audio features., e.g. MP3 ring tone.
Connectivity, and Storage
MT6223D supports UART as well as Bluetooth interface. Also, necessary peripheral blocks are
embedded for a voice centric phone: Keypad Scanner with the capability to detect multiple key
presses, SIM Controller, Alerter, Real Time Clock, PWM, Serial LCD Controller, and General
Purpose Programmable I/Os.
Audio
Using a highly integrated mixed-signal Audio Front-End, architecture of MT6223D allows for
easy audio interfacing with direct connection to the audio transducers. The audio interface
integrates D/A and A/D Converters for Voice band, as well as high resolution Stereo D/A
Converters for Audio band. In addition, MT6223D also provides Stereo Input and
Analog Mux. MT6223D also supports AMR codec to adaptively optimize speech and audio quality.

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Radio
MT6223D integrates a mixed-signal Baseband front-end in order to provide a well-organized
radio interface with flexibility for efficient customization. It contains gain and offset calibration
mechanisms, and filters with programmable coefficients for comprehensive compatibility control on
RF modules. This approach also allows the usage of a high resolution D/A Converter for controlling
VCXO or crystal, thus reducing the need for expensive TCVCXO. MT6223D achieve great
MODEM performance by utilizing 14-bit high resolution A/D Converter in the RF downlink
path. Furthermore, to reduce the need for extra external current-driving component, the driving
strength of some BPI outputs is designed to be configurable.
Debug Function
The JTAG interface enables in-circuit debugging of software program with the ARM7EJ-S core.
With this standardized debugging interface, MT6223D provides developers with a wide set of
options in choosing ARM development kits from different third party vendors. Low Power Features
MT6223D offers various low-power features to help reduce system power consumption. These
features include Pause Mode of 32KHz clocking at Standby State, Power Down Mode for individual
peripherals, and Processor Sleep Mode. In addition, MT6223D are also fabricated in advanced low
leakage CMOS process, hence providing an overall ultra low leakage solution.
Power Management
MT6223D integrates all regulators that a voice-centric phone needs. Seven LDOs optimized for
Specific GSM/GPRS baseband sub-systems are included, and a RF transceiver needed LDO is
also built-in. Besides Li-Ion battery charge function, SIM card level shifter interface, two open-drain
output switches to control the LED and vibrator are equipped. Other power management schemes
such as thermal overload protection, Under Voltage Lock-out Protection (UVLO), over voltage
protection and oower-on reset and start-up timer are also MT6223D features. Besides, 3 NMOS
switches controlling the RGB LEDs are also embedded to reduce BOM coount.
Package
The MT6223D device is offered in 9mm×9mm, 224-ball,
0.5 mm pitch, TFBGA package.
3.1.2 Platform Feature
General
Integrated voice-band, audio-band and base-band analog front ends
TFBGA 9mm×9mm, 224-ball, 0.5 mm pitch package
MCU Subsystem
ARM7EJ-S 32-bit RISC processor
High performance multi-layer AMBA bus
Java hardware acceleration for fast Java-based games and applets
Operating frequency: 26/52 MHz

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Dedicated DMA bus
7 DMA channels
320K bits on-chip SRAM
On-chip boot ROM for Factory Flash Programming
Watchdog timer for system crash recovery
3 sets of General Purpose Timer
Circuit Switch Data coprocessor
Division coprocessor
External Memory Interface
Supports up to 2 external devices
Supports 16-bit memory components with maximum size of up to 128M Bytes each
Supports Flash and SRAM/PSRAM with Page Mode or Burst Mode
Industry standard serial LCD Interface
Supports multi-media companion chips with 8/16 bits data width
Flexible I/O voltage of 1.8V ~ 2.8V for memory interface
Configurable driving strength for memory interface
User Interfaces
5-row × 7-column keypad controller with hardware scanner
Supports multiple key presses for gaming
SIM/USIM Controller with hardware T=0/T=1 protocol control
Real Time Clock (RTC) operating with a separate power supply
General Purpose I/Os (GPIOs)
2 Sets of Pulse Width Modulation (PWM) Output
Alerter Output with Enhanced PWM or PDM
6 external interrupt lines
Security
Supports security key and 59 bit chip unique ID
Connectivity
3 UARTs with hardware flow control and speed up to 921600 bps
DAI/PCM and I2S interface for Audio application
Low Power Schemes
Power Down Mode for analog and digital circuits
Processor Sleep Mode
Pause Mode of 32KHz clocking at Standby State
3-channel Auxiliary 10-bit A/D Converter for application usage other than battery monitoring
Power and Supply Management
2.8V to 5.5V Input Range
Charger Input up to 8V
Seven LDOs Optimized for Specific GSM

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Sub-systems
One LDO for RF transceiver
High Operation Efficiency and Low Stand-by Current
Li-Ion Battery Charge function
SIM Card Interface
Two Open-Drain Output Switches to Control the LED and Vibrator
Three NMOS switches to control RGB LEDs
Thermal Overload Protection
Under Voltage Lock-out Protection
Over Voltage Protection
Power-on Reset and Start-up Timer
Test and Debug
Built-in digital and analog loop back modes for both Audio and Baseband Front-End
DAI port complying with GSM Rec.11.10
JTAG port for debugging embedded MCU
3.1.3 MODEM Features
Radio Interface and Baseband Front End
GMSK modulator with analog I and Q channel outputs
10-bit D/A Converter for uplink baseband I and Q signals
14-bit high resolution A/D Converter for downlink baseband I and Q signals
Calibration mechanism of offset and gain mismatch for baseband A/D Converter and D/A
Converter
10-bit D/A Converter for Automatic Power Control
13-bit high resolution D/A Converter for Automatic Frequency Control
Programmable Radio RX filter with adaptive bandwidth control
Dedicated Rx filter for FB acquisition
2 Channels Baseband Serial Interface (BSI) with 3-wire control
Bi-directional BSI interface. RF chip register read access with 3-wire or 4-wire interface.
10-Pin Baseband Parallel Interface (BPI) with programmable driving strength
Multi-band support
Voice and Modem CODEC
Dial tone generation
Voice Memo
Noise Reduction
Echo Suppression
Advanced Sidetone Oscillation Reduction
Digital sidetone generator with programmable gain

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Two programmable acoustic compensation filters
GSM/GPRS quad vocoders for adaptive multirate (AMR), enhanced full rate (EFR), full rate
(FR) and half rate (HR)
GSM channel coding, equalization and A5/1, A5/2 and A5/3 ciphering
GPRS GEA1, GEA2 and GEA3 ciphering
Programmable GSM/GPRS Modem
GSM Circuit Switch Data
GPRS Class 12
Voice Interface and Voice Front End
Two microphone inputs sharing one low noise amplifier with programmable gain and automatic
gain control (AGC) mechanism
Voice power amplifier with programmable gain
2nd order Sigma-Delta A/D Converter for voice uplink path
D/A Converter for voice downlink path
Supports half-duplex hands-free operation
Compliant with GSM 03.50
3.1.4 Multi-Media Features
LCD Interface
Dedicated Serial Interface supports 1 external Serial interface for LCM
LCD Controller
Supports LCM format: RGB332, RGB444, RGB565, RGB666, RGB888
Supports LCD module with maximum resolution up to 176x220 at 16bpp
2 layer blending
Supports hardware display rotation for each layer
Audio CODEC
Wavetable synthesis with up to 64 tones
Advanced wavetable synthesizer capable of generating simulated stereo
Wavetable including GM full set of 128 instruments and 47 sets of percussions
PCM Playback and Record
Digital Audio Playback
Audio Interface and Audio Front End
Supports I2S interface
High resolution D/A Converters for Stereo Audio playback
Stereo analog input for stereo audio source
Analog multiplexer for Stereo Audio
FM Radio Recording
Stereo to Mono Conversion

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3.1.5 General Description
Figure3-1-2 details the block diagram of MT6223D. on a dual-processor architecture,
MT6223D integrates both an ARM7EJ-S core and 2 digital signal processor cores. ARM7EJ-S is
the main processor that is responsible for running 2G and 2.5G protocol software. Digital signal
processors handle the MODEM algorithms as well as advanced audio functions.
Except for some mixed-signal circuitries, the other building blocks in MT6223D are connected to
either the microcontroller or one of the digital signal processors.
Specifically, MT6223D consist of the following subsystems:
 Microcontroller Unit (MCU) Subsystem - includes an ARM7EJ-S RISC processor and
its accompanying memory management and interrupt handling logics.
 Digital Signal Processor (DSP) Subsystem - includes 2 DSP cores and their
accompanying memory, memory controller, and interrupt controller.
 MCU/DSP Interface - where the MCU and the DSPs exchange hardware and
software information.
 Microcontroller Peripherals - includes all user interface modules and RF control
interface modules.
 Microcontroller Coprocessors - runs computing-intensive processes in place of
Microcontroller.
 DSP Peripherals - hardware accelerators for GSM/GPRS/EGDE channel codec.
 Voice Front End - the data path for converting analog speech from and to digital
speech.
 Audio Front End - the data path for converting stereo audio from stereo audio source
 Baseband Front End - the data path for converting digital signal from and to analog
signal of RF modules.
 Timing Generator - generates the control signals related to the TDMA frame timing.
 Power, Reset and Clock subsystem - manages the power, reset, and clock
distribution inside MT6223D
 LDOs, Power-on sequences, swicthes and SIM level shifters.