LG LG-A290 User manual

Internal Use Only
Service Manual
LG-A290
Date: January, 2012 / Issue 1.0

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LGE Internal Use Only Copyright © 2012 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Table Of Contents
1. INTRODUCTION............................................................... 3
1.1 Purpose ................................................................................................3
1.2 Regulatory Information .................................................................3
1.3 Abbreviations.....................................................................................5
2. SYSTEM SPECIFICATION .................................................7
2.1 H/W Features......................................................................................7
2.2 Technical Specification...................................................................9
3. TECHNICAL BRIEF..........................................................14
3.1 Digital Main Processor................................................................. 14
3.2 Power Management .................................................................... 19
3.3 FEM with integrated Power Amplifier Module
(SKY77550, U400).......................................................................... 24
3.4 Clocks................................................................................................. 26
3.5 RFSYS of MT6253 (U101)............................................................ 28
3.6 MEMORY(PF38F5060M0Y3DK, U100 ).................................. 30
3.7 BT & FM Module(MT6626, U401) ........................................... 34
3.8 SIM Card Interface......................................................................... 38
3.9 Micro-SD Card Interface ............................................................. 41
3.10 LCD Interface................................................................................ 44
3.11 Battery Charger Interface / MUIC......................................... 46
3.12 Keypad Interface......................................................................... 48
3.13 Audio Front-End.......................................................................... 51
3.14 Camera Interface......................................................................... 55
3.15 KEY BACLKLIGHT LED Interface ............................................ 57
3.16 Vibrator Interface ........................................................................ 58
3.17 Torch LED Interface.................................................................... 59
4. TROUBLE SHOOTING ....................................................60
4.1 RF Component .............................................................................. 60
4.2 RX Trouble ....................................................................................... 61
4.3 TX Trouble........................................................................................ 65
4.4 Power On Trouble.......................................................................... 69
4.6 Vibrator Trouble ............................................................................. 74
4.7 LCD Trouble ..................................................................................... 76
4.8 Camera Trouble.............................................................................. 79
4.9 Speaker/ Receiver Trouble......................................................... 83
4.10 3.5φ Headset Trouble................................................................ 85
4.11 Microphone Trouble.................................................................. 88
4.12 SIM1 Card Interface Trouble................................................... 90
4.13 SIM2 Card Interface Trouble.................................................. 92
4.14 SIM3 Card Interface Trouble.................................................. 94
4.15 KEY backlight Trouble............................................................... 96
4.16 Torch Trouble................................................................................ 98
4.17 Micro SD Trouble ......................................................................100
4.18 Bluetooth Trouble ....................................................................102
4.19 FM Radio Trouble ....................................................................104
5. DOWNLOAD.................................................................106
6. BLOCK DIAGRAM.........................................................119
7. Circuit Diagram ...........................................................120
8 BGA PIN MAP ................................................................124
9. PCB LAYOUT.................................................................126
10. ENGINEERING MODE ................................................128
11 RF CALIBRATION ........................................................129
11.1 Configuration of Tachyon .....................................................129
11.2 How to use Tachyon.................................................................131
12 EXPLODED VIEW & REPLACEMENT PART LIST ........133
12.1 EXPLODED VIEW........................................................................133
12.2 ReplacementParts ....................................................................134
12.3 Accessory .....................................................................................151

1. INTRODUCTION
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LGE Internal Use Only Copyright © 2012 LG Electronics. Inc. All right reserved.
Only for training and service purposes
1. INTRODUCTION
1.1 Purpose
This manual provides the information necessary to repair, calibration, 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 does
not warrant that this product is immune from the above case but will prevent unauthorized use of common-carrier
telecommunication 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 unauthorized
alternations or repair may affect the regulatory status of the system and may void any remaining warranty.

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LGE Internal Use Only Copyright © 2012 LG Electronics. Inc. All right reserved.
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1. INTRODUCTION
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 Device (ESD), are indicated by the sign.
Following information is ESD handling:
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 package as described.
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1. INTRODUCTION
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LGE Internal Use Only Copyright © 2012 LG Electronics. Inc. All right reserved.
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1.3 Abbreviations
For the purposes of this manual, following abbreviations apply:
APC Automatic Power Control
BB Baseband
BER Bit Error Ratio
CC-CV Constant Current – Constant Voltage
DAC Digital to Analog Converter
DCS Digital Communication System
dBm dB relative to 1 milli watt
DSP Digital Signal Processing
EEPROM Electrical Erasable Programmable Read-Only Memory
ESD Electrostatic Discharge
FPCB Flexible Printed Circuit Board
GMSK Gaussian Minimum Shift Keying
GPIB General Purpose Interface Bus
GSM Global System for Mobile Communications
IPUI International Portable User Identity
IF Intermediate Frequency
LCD Liquid Crystal Display
LDO Low Drop Output
LED Light Emitting Diode
OPLL Offset Phase Locked Loop
PAM Power Amplifier Module

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1. INTRODUCTION
PCB Printed Circuit Board
PGA Programmable Gain Amplifier
PLL Phase Locked Loop
PSTN Public Switched Telephone Network
RF Radio Frequency
RLR Receiving Loudness Rating
RMS Root Mean Square
RTC Real Time Clock
SAW Surface Acoustic Wave
SIM Subscriber Identity Module
SLR Sending Loudness Rating
SRAM Static Random Access Memory
PSRAM Pseudo SRAM
STMR Side Tone Masking Rating
TA Travel Adapter
TDD Time Division Duplex
TDMA Time Division Multiple Access
UART Universal Asynchronous Receiver/Transmitter
VCO Voltage Controlled Oscillator
VCTCXO Voltage Control Temperature Compensated Crystal Oscillator
WAP Wireless Application Protocol

2. PERFORMANCE
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LGE Internal Use Only Copyright © 2012 LG Electronics. Inc. All right reserved.
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2. SYSTEM SPECIFICATION
2.1 H/W Features
Item Feature Comment
Standard Battery Lithium Ion, 3.7V 1500mAh
Stand by TIME >450 hr., Min.@PP9
Stand by time >500 hr., Min.@PP5
Talk time
>6.0hr., Min.@GSM900, PL=5
>14.0 hr., Min.@GSM900, PL=13
>8 hr., Min.@DCS, PL=0
>14 hr., Min.@DCS, PL=9
Charging time Approx. 3 hours 30 min.
RX Sensitivity GSM, EGSM: -109dBm, DCS: -109dBm
TX output power GSM, EGSM: 32.3dBm(Level 5),
DCS , PCS: 29.5dBm(Level 0)
GPRS compatibility Class 10
SIM card type 3V Small
Display MAIN : TFT 176 × 220(QCIF) pixel 262K Color
Status Indicator
KEY TOTAL 22EA
Hard icons. Key Pad
Numeric(12EA : 0 ~ 9, #, *) Navigation Key OK Key(5EA)
Menu Key, Clear Key, Send Key, End Key,
SIM Switch Key(5EA)
ANT Internal
EAR Phone Jack Yes(3.5Ø)
PC Synchronization Yes
Speech coding EFR/FR/HR
Data and Fax Yes
Vibrator Yes
Loud Speaker Yes
Voice Recoding Yes

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2. PERFORMANCE
Item Feature Comment
Microphone Yes
Speaker/Receiver 18 x 12 Speaker/Receiver
Travel Adapter Yes
MIDI SW MIDI (Mono SPK)
Camera 1.3M
Bluetooth / FM Radio Bluetooth version 2.1 / 76~108MHz supported

2. PERFORMANCE
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LGE Internal Use Only Copyright © 2012 LG Electronics. Inc. All right reserved.
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2.2 Technical Specification
Item Description Specification
1 Frequency Band
GSM850
TX: 824 ~ 849 MHz
RX: 869 ~ 894 MHz
DCS
TX: 1710 ~ 1785 MHz
RX: 1805 ~ 1880 MHz
PCS
TX: 1850 ~ 1910 MHz
RX: 1930 ~ 1990 MHz
EGSM
TX: 880 ~ 915MHz
RX: 925 ~ 960 MHz
2 Phase Error RMS < 5 degrees
Peak < 20 degrees
3 Frequency Error < 0.1ppm
4 Power Level
GSM850 / EGSM
Level Power Toler. Level Power Toler.
5 33 dBm ±2dB 13 17 dBm ±3dB
6 31 dBm ±3dB 14 15 dBm ±3dB
7 29 dBm ±3dB 15 13 dBm ±3dB
8 27 dBm ±3dB 16 11 dBm ±5dB
9 25 dBm ±3dB 17 9 dBm ±5dB
10 23 dBm ±3dB 18 7 dBm ±5dB
11 21 dBm ±3dB 19 5 dBm ±5dB
12 19 dBm ±3dB
DCS / PCS
Level Power Toler. Level Power Toler.
0 30 dBm ±2dB 8 14 dBm ±3dB
1 28 dBm ±3dB 9 12 dBm ±4dB
2 26 dBm ±3dB 10 10 dBm ±4dB
3 24 dBm ±3dB 11 8 dBm ±4dB
4 22 dBm ±3dB 12 6 dBm ±4dB
5 20 dBm ±3dB 13 4 dBm ±4dB
6 18 dBm ±3dB 14 2 dBm ±5dB
7 16 dBm ±3dB 15 0 dBm ±5dB

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2. PERFORMANCE
Item Description Specification
5Output RF Spectrum
(due to modulation
GSM850 / EGSM
Offset from Carrier (kHz). Max. dBc
100 +0.5
200 -30
250 -33
400 -60
600 ~ <1,200 -60
1,200 ~ <1,800 -60
1,800 ~ <3,000 -63
3,000 ~ <6,000 -65
6,000 -71
DCS/ PCS
Offset from Carrier (kHz). Max. dBc
100 +0.5
200 -30
250 -33
400 -60
600 ~ <1,200 -60
1,200 ~ <1,800 -60
1,800 ~ <3,000 -65
3,000 ~ <6,000 -65
6,000 -73
6Output RF Spectrum
(due to switching transient)
GSM850 / EGSM
Offset from Carrier (kHz). Max. dBm
400 -19
600 -21
1,200 -21
1,800 -24

2. PERFORMANCE
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LGE Internal Use Only Copyright © 2012 LG Electronics. Inc. All right reserved.
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Item Description Specification
6Output RF Spectrum
(due to switching transient)
DCS/ PCS
Offset from Carrier (kHz). Max. dBm
400 -22
600 -24
1,200 -24
1,800 -27
7 Spurious Emissions Conduction, Emission Status
8 Bit Error Ratio
GSM850, EGSM
BER (Class II) < 2.439% @-102 dBm
DCS,PCS
BER (Class II) < 2.439% @-102 dBm
9 RX Level Report Accuracy ± 3 dB
10 SLR 15±3 dB
11 Sending Response
Frequency (Hz) Max.(dB) Min.(dB)
100 -12 -
200 0 -
300 0 -12
1,000 0 -6
2,000 4 -6
3,000 4 -6
3,400 4 -9
4,000 0 -
12 RLR(Norminal) 4± 3 dB

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2. PERFORMANCE
Item Description Specification
13 Receiving Response
Frequency (Hz) Max.(dB) Min.(dB)
100 -6 -
200 2 -
300 2 -9
500 * *
1,000 2 -7
3,000 2 *
3,400 2 -12
4,000 2
* Mean that Adopt a straight line in between 300 Hz and 1,000 Hz to
be Max. level in the range.
14 STMR(Vol. Nominal) >17dB
15 Echo Loss >58dB
16 Idle Noise Sending < -64dBm0p
17 Idle Noise Receiving < -54dBm0P(Volume Max)
18 System frequency
(13 MHz) tolerance ≤ 2.5 ppm
19 32.768KHz tolerance ≤ 30 ppm
20 Ringer Volume
At least 58 dB spl under below conditions:
1. Ringer set as ringer.
2. Test distance set as 100 cm
21 Charge Current
Fast Charge : Typ. 600 mA
Slow Charge : Typ. 500mA
Total Charging Time : < Approx. 3 hours 30min.

3. TECHNICAL BRIEF
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Item Description Specification
22 Antenna Display
Bar Number Power
4 over -91dBm±2dBm
4 -> 3 -91dBm±2dBm
3 -> 2 -99dBm±2dBm
2 -> 1 -103dBm±2dBm
1 -> 0 -105dBm±2dBm
23 Battery Indicator
Battery Bar Number Voltage
3 ≥ 3.75± 0.05 V
3 -> 2 3.75 ± 0.05 V
2 -> 1 3.65 ± 0.05 V
1 -> 0 3.5 ± 0.05 V
24 Low Voltage Warning
( Blinking Bar)
≤ 3.5 ± 0.05V (Call), every 1 minute
≤ 3.5 ± 0.05V (Standby), every 3 minute.
25 Forced shut down
Voltage 3.35 ± 0.05V
26 Sustain RTC
without battery Over 1 min(Super Cap : Polyacene Capacitor 10uAh)
27 Battery Type
Li-Ion Battery
Standard Voltage = 3.7 V
Battery full charge voltage = 4.2 V
Capacity: 1500mAh
28 Travel Charger
Switching-mode charger
Input: 90 ~ 264 V, 47/63 Hz
Output: 5.1 V, 700 mA

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3. TECHNICAL BRIEF
3. TECHNICAL BRIEF
3.1 Digital Main Processor
Figure. 3.1.1 MT6253 Hardware Block Diagram

3. TECHNICAL BRIEF
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LGE Internal Use Only Copyright © 2012 LG Electronics. Inc. All right reserved.
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3.1.1 General
• Integrated voice-band, audio-band and base-band analog front ends.
• Package:
– aQFN, 11.5x11.5x0.85 mm.
– 0.47 mm pitch.
– 260balls, 0.47mm pitch package.
3.1.2 MCU Subsystem
• ARM7EJ-S 32-bit RISC processor.
• High performance multi-layer AMBA bus.
• Operating frequency 52/104MHz.
• Dedicated DMA bus, 7DMA channels.
• 144KB 0n-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.
3.1.3 External Memory Interface
• Supports up to 3 external devices.
• Supports 16-bit memory components with maximum size of up to 64M Bytes for each bank.
• Supports Flash and SRAM/PSRAM with Burst Mode.
• Support legacy industry standard parallel LCD Interface.
• Suppport multi-media companion chips with 8/16 bits data width.
• Configurable driving strength for memory interface.
3.1.4 User Interface
• 6-row x 7-column keypad control with hardware scanner.
• Support multi key press 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).
• 1 set of Pulse Width Modulation(PWM) Output.
• Alerter Output with Enhanced PWM or PDM.
• Maximum 7 external interrupt lines.
3.1.5 Security
Support security key and 128bit chip unique ID. •

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3. TECHNICAL BRIEF
3.1.6 Connectivity
• 3 sets of UART with hardware flow control and speed up to 921600 bps.
• IrDA modulator/demodulator with hardware framer supports SIR mode of operation.
• HS/FS/LS USB 2.0 Device controller.
• Multi Media Card/Secure Digital Memory Card/Memory Stick/Memory Stick Prto/SDIO host controller.
• Supports SDIO interface for SDIO peripherals as well as WIFI connectivity.
• DAI/PCM and !2S interface for Audio application.
3.1.7 Low Power Schemes
• Power Down Mode for analog and digital circuits.
• Processor Sleep Mode.
• Pause Mode of 32KHs clocking at Standby State.
• 3-channel Auxiliary 10-bit A/D Converter for application usage other than battery monitoring.
3.1.8 Power and Supply Management
• 2.8V to 4.7V Input Range.
• Charger Input up to 8V.
• 11 sets of LDO Optimized Specific GSM Sub-systems.
• One LDO for RF transceiver.
• High Operation Efficiency and Low Stand-by Current.
• Dual SIM Card Interface.
• One boost regulator and Four Open-Drain Output Current Regulators to Supply/Control the LED.
• LDO type Vibrator.
• One NMOS switch to control R(GB) LED.
• Thermal Overload Protection.
• Under Voltage Lock-out Protection.
• Over Voltage Protection.
3.1.9 Integrated RF Receiver
• Direct conversion architecture.
• Quad band differential input LNAs.
• Quadrature RF mixers.
• Fully integrated channel filter with f3dB=150kHs.
• 95dB gain with 60dB gain control range.
• No IIP2 calibration.

3. TECHNICAL BRIEF
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3.1.10 Integrated RF Transmitter
• Offset phase lock loop.
• IQ modulator DC offset calibration by BB ADC/DAC.
• Precise quadrature by IF divide-by-4.
• Integrated loop filter.
3.1.11 Integrated RF Frequency Synthesizer
• Programmable fractional-N synthesizer.
• Integrated wide range RFVCO.
• Integrated loop filter.
• Fast setting time suitable for multi-slot SPRS applications.
3.1.12 Integrated RF Digitally-Controlled Crystal Oscillator(DCXO)
• One-pin 26MHz crystal oscillator.
• On-chip programmable capacitor array for cross tune.
3.1.13 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.
• Programmable Radio RX filter with adaptive bandwidth control.
• Dedicated Rx filter for FB acquisition.
• 6-Pin Baseband Parallel Interface(BRI) with programmable driving strength.
• Multi-band support.
3.1.14 Voice and Modem CODEC
• Digital tone generation.
• Voice Memo.
• Noise Reduction.
• Echo Suppression.
• Advanced Sidetone Oscillation Reduction.
• Digital sidetone generator with programmable gain.
• 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.

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3. TECHNICAL BRIEF
3.1.15 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.
• Supporter for voice downlink path.
• Supports half-duplex hands-free operation.
• Compliant with GSM 03.05
3.1.16 LCD Interface
• Dedicated Parallel Interface supports 2 external 8/9 bit Parallel Interface, and Serial interface for LCM.
3.1.17 LCD Controller
• Supports LCM format: RGB332, RGB444, RGB565, RGB666, RGB888.
• Supports LCD module with maximum resolution up to 240x320 at 16bpp.
• Capable of combining display memories with up to 4 blending layers.
• Accelerated Gamma correction with programmable gamma table.
• Supports hardware display rotation for each layer.
3.1.18 Audio CODEC
• Wavetable synthesis with up to 64 tones.
• Advanced wavetable synthesizer capable of generating and 47 sets of percussions.
• PCM Playback and Record.
• Digital Audio Playback.
3.1.19 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.
• HE-AAC decode support.

3. TECHNICAL BRIEF
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3.2 Power Management
Power management unit, so called PMU, is integrated into analog part. To facilitate software control and interface design,
PMU control share the CCI interface along with other analog parts, such as BBTX, BBRX, VBI and ABI during FT.
Charger
System LDOS
KPLED
Driver Buck
SIM IO 1 Boost
SIM IO 2 Vibrator
Driver
Sequence /
Protection
Backlight
Driver
Speaker
Driver
Power-on
Logic
MT6253 PMU System
Figure. 3.2.1 PMU system block diagram
3.2.1 Low Dropout Regulators(LDOs), Buck converterand Reference
The PMU Integrates 12 LDOs that are optimized for their given functions by balancing quiescent current, dropout
voltage, line/load regulation, and output noise.
RF LDO (Vrf)
The RF LDO is a linear regulator that could source 180mA (max) with 2.8V output voltage. It supplies the RF circuitry of
the handset. The LDO is optimized for high performance and adequate quiescent current.

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3. TECHNICAL BRIEF
Digital Core Buck Converter (Vcore)
The digital core regulator is a DC-DC step-down (Buck converter) that could source 200mA(max) with 1.2V to 0.9V
programmable output voltage based on software register setting. It supplies the power for baseband circuitry of the SoC.
The buck converter is optimized for high efficiency and low quiescent current.
Digital IO LDO (Vio)
The digital IO LDO is a linear regulator that could source 100mA (max) with 2.8V output voltage. It supplies the the
power for baseband circuitry of the SoC. The LDO is optimized for very low quiescent current and turns on automatically
together with Vm/Va LDOs.
Analog LDO (Va)
The analog LDO is a linear regulator that could source 100mA (max) with 2.8V output voltage.
It supplies the analog sections of the SoC. The LDO is optimized for low frequency ripple rejection in order to reject the
ripple coming from the burst at 217Hz of RF power amplifier.
TCXO LDO (Vtcxo)
The TCXO LDO is a linear regulator that could source 20mA (max) with 2.8V output voltage.
It supplies the temperature compensated crystal oscillator, which needs ultra low noise supply
with very good ripple rejection.
Single-Step RTC LDO (Vrtc)
The single-step RTC LDO is a linear regulator that can charge up a capacitor-type backup coin cell to 2.8V, which also
supplies the RTC module even at the absence of the main battery. The single-step LDO features the reverse current
protection and is optimized for ultra low quiescent current while sustaining the RTC function as long as possible.
Memory LDO (Vm)
The memory LDO is a linear regulator that could source 200mA (max) with 1.8V or 2.8V output voltage selection based on
the supply specification of memory chips. It supplies the memory circuitry in the handset. The LDO is optimized for very
low quiescent current with wide output loading range.
SIM LDO (Vsim)
The SIM LDO is a linear regulator that could source 80mA (max) with 1.8V or 3.0V output voltage selection based on
the supply specs of subscriber identity modules (SIM) card. It supplies the SIM card and SIM level shifter circuitry in the
handset. The Vsim LDO is controlled independently by the register named VSIM_EN.
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