LG GB175 User manual

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GB175
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………………16
3.1 Digital Main Processor(MT6225)……….16
3.2 Power Amplifier Module(SKY77518)…....23
3.3 Transceiver Module(AD6548)…………..24
3.4 PMIC (MT6318)……………………….26
3.5 Memory Module (PF38F4050M0Y0CG)…….28
3.6 FM Radio Module (Si4708)…………..32
3.7 Antenna Switch Module (B9308)……...34
3.8 LCD Interface……………………….…35
3.9 SIM& Micro SD Card Interface…..…..37
3.10 KEYPAD Interface…………………..38
3.11 Battery Charging Block Interface…..39
3.12 Audio Interface……………….….…..40
3.13 Vibrator Interface….………………...42
4. TROUBLE SHOOTING…………..43
4.1 Power On Trouble…………………….43
4.2 SIM Card Trouble……………………..45
4.3 Vibrator Trouble……………………….47
4.4 Keypad Trouble……………………….48
4.5 RTC Trouble…………………………...50
4.6 Key Backlight Trouble………………...53
4.7 LCM Backlight Trouble……………….56
4.8 LCM Trouble……………….………….58
4.9 Microphone Trouble…………………..60
4.10 Receiver Trouble…………………….62
4.11 Speaker Trouble……………………..64
4.12 Headphone Trouble…………………66
4.13 Charging Trouble…………………….69
4.14 FM Radio Trouble…………………...71
4.15 RF Trouble…………………………...73
5. DOWNLOAD………………...…….78
5.1 Download setup………………………78
5.2 Download Process……………………79
6. BLOCK DIAGRAM……………….87
7. CIRCUIT DIAGRMA……………...88
8. BGA IC PIN Check……………….96
9. PCB LAYOUT……………………..99
10.ENGINEERING MODE…………101
11. CALIBRATION………………….105
11.1 Test Equipment Setup……………..105
11.2 Calibration Steps…………………...106
12. STAND ALONE TEST…………145
12.1 Test Configuration………………….145
12.2 META tool Install process…………146
12.3 Rx Test………………………………149
12.4 Tx Test……………………………....153
13. EXPLODED VIEW&
REPLACEMENT PART LIST……..155
13.1 Exploded View……………………..155
13.2 Replacement Part list..…………....157

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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.
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.

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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 MT6225 Media Tek / AIT
Form Factor Bar type
Dimension (mm) 103 x 46 x 13.65
RF Band Dual Band 900/1800 Internal Antenna
Data GPRS Class 10
Main Display 1.5” TFT 65K color, 128x128 Pixels
Battery 950 mA h Same as LG6/7
Audio player Yes MP3/AAC/(AAC+ w/o DRM)
FM Receiver Yes , US/Europe
band(87.5~108MHz)
Loud Speaker Yes
Memory Size 256Mb NOR Flash +64Mb PSRAM 6225 support 1.8 or not
User Memory Yes 6M Bytes
Memory Card Yes Micro SD
Scheduled FM recording Yes
FM as alarm Yes
Embedded FM antenna Yes Pogo pin contact FPC type
FM Antenna on Battery cover.
Audio player--real resuming Yes For MP3 only
USB Yes
Slave 1.1
WAP Yes
V2.0
Java Yes
DRM No OMA DRM v1.0
Music Equalizer Yes Follow MTK
In flight mode Yes