LG KP202 User manual

Service Manual Model : KP202
Service Manual
KP202
Date: April, 2007 / Issue 1.0

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1. INTRODUCTION ...............................5
1.1 Purpose .................................................. 5
1.2 Regulatory Information............................ 5
1.3 Abbreviations .......................................... 7
2. PERFORMANCE...............................9
2.1 H/W Features...........................................9
2.2 Technical Specification ..........................10
3. TECHNICAL BRIEF ........................15
3.1 Power Amplifier (SKY77318, U500).......15
3.2 Transceiver (AD6548, U501) .................17
3.3 FEM for Triband .....................................19
3.4 26 MHz Clock (Crystal, X500)................20
3.5 Baseband Processor (AD6720 , U104)..21
3.6 Display and Interface .............................28
3.7 Camera Interface(AIT701G , U402).......30
3.8 Keypad Switches and Scanning ............32
3.9 Microphone ............................................33
3.10 Main Speaker.......................................34
3.11 Headset Interface.................................35
3.12 Key Back-light Illumination...................36
3.13 LCD Back-light Illumination..................37
3.14 VIBRATOR...........................................38
4. TROUBLE SHOOTING ...................39
4.1 RF Component.......................................39
4.2 RX Trouble.............................................40
4.3 TX Trouble .............................................45
4.4 Power On Trouble..................................51
4.5 Charging Trouble ...................................53
4.6 Vibrator Trouble .....................................55
4.7 LCD Trouble...........................................57
4.8 Camera Trouble .....................................60
4.9 Speaker Trouble ....................................63
4.10 SIM Card Interface Trouble..................65
4.11 Earphone Trouble ................................67
4.12 KEY backlight Trouble .........................69
4.13 Receiver Trouble..................................71
4.14 Microphone Trouble .............................73
4.15 RTC Trouble ........................................75
4.16 Indicator LED Trouble ..........................77
4.17 Folder on/off Trouble............................79
5. DOWNLOAD.......................................81
5.1 Download ...............................................81
6. BLOCK DIAGRAM ..........................87
7. Circuit Diagram ..............................89
8. PCB LAYOUT..................................97
9. ENGINEERING MODE ..................103
9.1 BB Test [MENU 1]................................104
9.2 RF Test [MENU 2]................................106
9.3 MF mode [MENU 3] .............................106
9.4 Trace option [MENU 4] ........................107
9.5 Call timer [MENU 5] .............................107
9.6 Fact. Reset [MENU 6] ..........................107
9.7 S/W version..........................................107
10. STAND ALONE TEST .................108
10.1 Introduction ........................................108
10.2 Setting Method...................................108
10.3 Means of Test ....................................109
11. AUTO CALIBRATION..................111
11.1 Overview ............................................111
11.2 Equipment List ...................................111
11.3 Test Jig Operation..............................112
11.4 Procedure ..........................................113
11.5 AGC ...................................................115
11.6 APC....................................................115
11.7 ADC ...................................................115
12. EXPLODED VIEW &
REPLACEMENT PART LIST ..... 117
12.1 Exploded View .................................. 117
12.2 Replacement Parts ............................119
12.3 Accessory ......................................... 135
Table Of Contents

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1. INTRODUCTION
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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.
1. INTRODUCTION

1. INTRODUCTION
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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 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.

1. INTRODUCTION
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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

1. INTRODUCTION
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PAM Power Amplifier Module
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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2.1 H/W Features
2. PERFORMANCE
Item Feature Comment
Standard Battery Li-ion, 3.7V 830mAh
Talk time Up to 200min : GSM Tx Level 7
Stand by time Up to 200 hours (Paging Period: 5, RSSI: -85 dBm)
Charging time Approx. 2.5 hours
RX Sensitivity GSM, EGSM: -102dBm, DCS: -102dBm, PCS: -102dBm
TX output power GSM, EGSM: 32.5dBm(Level 5),
DCS , PCS: 29.5dBm(Level 0)
GPRS compatibility Class 10
SIM card type 3V,1.8V Small
Display MAIN : TFT 128 × 160 pixel 65K Color
SUB : MONO STN 96*64
Hard icons. Key Pad
0 ~ 9, #, *, Up/Down/Left/Right/Ok Navigation Key
Status Indicator Menu Key, Clear Key, Back Key, Confirm Key
Send Key, Volume Key, PWR Key, Camera Key, Hot Key
ANT Internal
EAR Phone Jack Yes (mono)
PC Synchronization Yes
Speech coding EFR/FR/HR
Data Yes
Vibrator Yes
Loud Speaker Yes
Voice Recoding Yes
Microphone Yes
Speaker/Receiver One way speaker
Travel Adapter Yes
MIDI SW MIDI (Mono SPK)
Camera VGA

2. PERFORMANCE
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2.2 Technical Specification
Item Description Specification
GSM
TX: 890 + n x 0.2 MHz
RX: 935 + n x 0.2 MHz (n=1~124)
PCS
1Frequency Band TX: 1850 + (n-511) x 0.2 MHz
RX: 1930+ (n-511) x 0.2 MHz (n=512~810)
DCS
TX: 1710 + (n-511) x 0.2 MHz
RX: 1805 + (n-511) x 0.2 MHz (n=512~885)
2Phase Error RMS < 5 degrees
Peak < 20 degrees
3Frequency Error < 0.1 ppm
GSM
Level Power Toler. Level Power Toler.
533 dBm 2dB 13 17 dBm 3dB
631 dBm 3dB 14 15 dBm 3dB
729 dBm 3dB 15 13 dBm 3dB
827 dBm 3dB 16 11 dBm 5dB
925 dBm 3dB 17 9 dBm 5dB
10 23 dBm 3dB 18 7 dBm 5dB
11 21 dBm 3dB 19 5 dBm 5dB
4Power Level 12 19 dBm 3dB
DCS/PCS
Level Power Toler. Level Power Toler.
030 dBm 2dB 8 14 dBm 3dB
128 dBm 3dB 9 12 dBm 4dB
226 dBm 3dB 10 10 dBm 4dB
324 dBm 3dB 11 8 dBm 4dB
422 dBm 3dB 12 6 dBm 4dB
520 dBm 3dB 13 4 dBm 4dB
618 dBm 3dB 14 2 dBm 5dB
716 dBm 3dB 15 0 dBm 5dB

2. PERFORMANCE
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Item Description Specification
GSM, 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
5Output RF Spectrum 6,000 -71
(due to modulation) 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
GSM, EGSM
Offset from Carrier (kHz) Max. (dBm)
Output RF Spectrum 400 -19
6(due to switching transient) 600 -21
1,200 -21
1,800 -24

2. PERFORMANCE
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Item Description Specification
DCS/PCS
Offset from Carrier (kHz). Max. (dBm)
Output RF Spectrum 400 -22
6(due to switching transient) 600 -24
1,200 -24
1,800 -27
7Spurious Emissions Conduction, Emission Status
GSM, EGSM
8Bit Error Ratio BER (Class II) < 2.439% @-102 dBm
DCS,PCS
BER (Class II) < 2.439% @-102 dBm
9RX Level Report Accuracy 3 dB
10 SLR 8 3 dB
Frequency (Hz) Max.(dB) Min.(dB)
100 -12 -
200 0 -
300 0 -12
11 Sending Response 1,000 0 -6
2,000 4 -6
3,000 4 -6
3,400 4 -9
4,000 0 -
12 RLR 2 3 dB
Frequency (Hz) Max.(dB) Min.(dB)
100 -12 -
200 0 -
300 2 -7
500 *-5
13 Receiving Response 1,000 0 -5
3,000 2 -5
3,400 2 -10
4,000 2
*Mean that Adopt a straight line in between 300 Hz
and 1,000 Hz to be Max. level in the range.

2. PERFORMANCE
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Item Description Specification
14 STMR 13 5 dB
15 Stability Margin > 6 dB
dB to ARL (dB) Level Ratio (dB)
-35 17.5
-30 22.5
-20 30.7
16 Distortion -10 33.3
033.7
731.7
10 25.5
17 Side Tone Distortion Three stage distortion < 10%
18 System frequency 2.5ppm
(13 MHz) tolerance
19 32.768KHz tolerance 30ppm
At least 65 dBspl under below conditions:
20 Ringer Volume 1. Ringer set as ringer.
2. Test distance set as 50 cm
21 Charge Current Fast Charge : < 600 mA
Slow Charge : < 120 mA
Antenna Bar Number Power
5-85 dBm ~
4-90 dBm ~ -86 dBm
22 Antenna Display 3 -95 dBm ~ -91 dBm
2-100 dBm ~ -96 dBm
1-105 dBm ~ -101 dBm
0~-105 dBm
Battery Bar Number Voltage
03.56V ~ 0.05 V
23 Battery Indicator 1 3.66V ~ 0.05 V
23.74V ~ 0.05 V
33.85V ~ 0.05 V
43.86V ~ 0.05 V ~
24 Low Voltage Warning 3.56 0.05 V (Call) every 1 minutes
3.50 0.05 V (Standby)

2. PERFORMANCE
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Item Description Specification
25 Forced shut down Voltage 3.35 0.03V
1 Li-ion Battery
26 Battery Type Standard Voltage = 3.7 V
Battery full charge voltage = 4.2 V
Capacity: 830mAh
Switching-mode charger
27 Travel Charger Input: 100 ~ 240 V, 50/60 Hz
Output: 5.2 V, 800 mA

3. TECHNICAL BRIEF
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3.1 Power Amplifier (SKY77318, U500)
The SKY77318 Power Amplifier Module (PAM) is designed in a low profile (1.2 mm), compact form
factor for quad-band cellular handsets comprising GSM850/900, DCS1800, and PCS1900 operation.
The PAM also supports Class 12 General Packet Radio Service (GPRS) multi-slot operation. The
module consists of separate GSM850/900 PA and DCS1800/PCS1900 PA blocks,
impedancematching circuitry for 50 Ω input and output impedances, and a Power Amplifier Control
(PAC) block with an internal current-sense resistor. The custom BiCMOS integrated circuit provides
the internal PAC function and interface circuitry. Fabricated onto a single Gallium Arsenide (GaAs) die,
one Heterojunction Bipolar Transistor (HBT) PA block supports the GSM850/900 bands and the other
supports the DCS1800 and PCS1900 bands. Both PA blocks share common power supply pins to
distribute current. The GaAs die, the Silicon (Si) die, and the passive components are mounted on a
multi-layer laminate substrate. The assembly is encapsulated with plastic over mold. RF input and
output ports of the SKY77318 are internally matched to a 50 Ω load to reduce the number of external
components for a quad-band design. Extremely low leakage current (2.5 µA, typical) of the dual PA
module maximizes handset standby time. The SKY77318 also contains band-select switching circuitry
to select GSM (logic 0) or DCS/PCS (logic 1) as determined from the Band Select (BS) signal. In
Figure 3.1 below, the BS pin selects the PA output (DCS/PCS OUT or GSM850/900 OUT) and the
Analog Power Control (VAPC) controls the level of output power. The VBATT pin connects to an
internal current-sense resistor and interfaces to an integrated power amplifier control (iPAC™)
function, which is insensitive to variations in temperature, power supply, process, and input power. The
ENABLE input allows initial turn-on of PAM circuitry to minimize battery drain.
3. TECHNICAL BRIEF
Figure 3.1 Functional Block Diagram

3. TECHNICAL BRIEF
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SKY77318 PAM Pin Configuration-20-Pin
Leadless (Top View)
Typical Case Makings
Table 4. SKY77318 Pin Names and Signal Descriptions
Pin Mame Description
1BSBand Select
2VCC1A VCC (to GSM 1st stage, DCS/PCS 1st stages, BiCMOS PAC)
3DCS/PCS IN RF input 1710-1910 MHz (DCS1800, PCS1900)
4GSM IN RF input 880-915 MHz (GSM)
5GND RF and DC Ground
6VCC1B VCC (to GSM 2nd stage, DCS/PCS 2nd stages)
7GND RF and DC Ground
8GND RF and DC Ground
9GND RF and DC Ground
10 GND RF and DC Ground
11 GSM OUT RF Output 880-915 MHz (GSM)
12 GND RF and DC Ground
13 GND RF and DC Ground
14 GND RF and DC Ground
15 DCS/PCS_OUT RF Output 1710-1910 MHz (DCS 1800, PCS1900)
16 GND RF and DC Ground
17 VBATT Battery input to high side of internal sense resistor
18 ENABLE BiCMOS Enable
19 RSVD(GND) RF and DC Ground
20 VAPC Power Control Bias Voltage
GMD PAD GND Ground Pad, device underside

3. TECHNICAL BRIEF
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3.2 Transceiver (AD6548, U501)
The AD6548 provides a highly integrated direct conversion radio solution that combines, on a single
chip, all radio and power management functions necessary to build the most com-pact GSM radio
solution possible. The only external components required for a complete radio design are the Rx
SAWs, PA, Switchplexer and a few passives enabling an extremely small cost effective GSM Radio
solution. The AD6548 uses the industry proven direct conversion receiver architecture of the
OthelloTM family. For Quad band applications the front end features four fully integrated
programmable gain differential LNAs. The RF is then down converted by quad-rature mixers and then
fed to the baseband programmable-gain amplifiers and active filters for channel selection. The
Receiver output pins can be directly connected to the baseband analog processor. The Receive path
features automatic calibration and tracking to remove DC offsets.
The transmitter features a translation-loop architecture for directly modulating baseband signals onto
the integrated TX VCO. The translation-loop modulator and TX VCO are extremely low noise removing
the need for external SAW filters prior to the PA. The AD6548 uses a single integrated LO VCO for
both the receive and the transmit circuits. The synthesizer lock times are optimized for GPRS
applications up to and including class 12. AD6548 incorporates a complete reference crystal
calibration system. This allows the external VCTCXO to be replaced with a low cost crystal. No other
external components are required. The AD6548 uses the traditional VCTCXO reference source. The
AD6548 also contains on-chip low dropout voltage regulators (LDOs) to deliver regulated supply
voltages to the functions on chip, with a battery input voltage of between 2.9V and 5.5V.
Comprehensive power down options are included to minimize power consumption in normal use. A
standard 3 wire serial interface is used to program the IC. The interface features low-voltage digital
interface buffers compatible with logic levels from 1.6V to 2.9V.
Figure 3.2 AD6548 Block Diagram

3. TECHNICAL BRIEF
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COMPLIANT TO JEDEC STANDARDS MO-220-VHHD-2
AD6548/9 Pin Descriptions

3. TECHNICAL BRIEF
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3.3 FEM for Triband
Table 3.3.1 Band SW Logic Table
Figure 3.3.1 FEM CIRCUIT DIAGRAM
24
18
NC1
NC2 19
PCS_RX+ 13
12
PCS_RX-
TX1G 6
TX2G 8
VCTRL1
22
21 VCTRL2
20 VCTRL3
3VDD
YGHF-S006T
ANT
1
DCS_RX+ 15
14
DCS_RX-
EGSM_RX+ 17
16
EGSM_RX-
2GND1
25
GND10 GND11 26
4GND2
GND3
5
7GND4
GND5
9
10 GND6
11
GND7 GND8 23 GND9
FL500
56p
C538
2V8_VEXT
0.1u
C539
Tx 900 Tx 1800/1900 RX EGSM RX DCS RX PCS
Vdd H H H H H
Vctrl1 H H L L L
Vctrl2 L H H L L
Vctrl3 L L L H L

3. TECHNICAL BRIEF
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3.4 26 MHz Clock (Crystal, X500)
The 26 MHz clock (X500) consists of a XO( Crystal Oscillator) which oscillates at a frequency of 26
MHz. The AD6548 requires only an external low cost crystal as the frequency reference. The circuitry
to oscillate the crystal and tune its frequency is fully integrated. The Oscillator is a balanced
implementation requiring the crystal to be connected across 2 pins. There is a programmable capacitor
array included for coarse tuning of fixed offsets (e.g. crystal manufacturing tolerance), and an
integrated varactor for dynamic control. The oscillator is designed for use with a 26MHz crystal.
Dedicated control software ensures excellent frequency stability under all circumstances.
2
34
26MHz
X500
NX3225DA(W-191-451)
1
Figure 3.4 CRYSTAL CIRCUIT DIAGRAM

3. TECHNICAL BRIEF
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3.5 Baseband Processor (AD6720 , U104)
• AD6720 is an ADI designed processor
• AD6720 consists of
1. Control Processor Subsystem including:
• 32-bit MCU ARM7TDMI® Control Processor
• 39 MHz operation at 1.8V
• 1Mb of on-chip System SRAM Memory
2. DSP Subsystem including:
• 16-bit Fixed Point DSP Processor
• 91 MIPS[1] at 1.8V
• Data and Program SRAM
• Program Instruction Cache
• Full Rate, Enhanced Full Rate and Half Rate
• Speech Encoding/Decoding
• Capable of Supporting AMR & PDC Speech Algorithms
3. Peripheral Functions
• Parallel and Serial Display Interface
• Keypad Interface
• Flash Memory Interface
• Page-Mode Flash Support
• 1.8V and 3.0V, 64 kbps SIM Interface
• Universal System Connector Interface
• Data Services Interface
• Battery Interface (e.g. Dallas)
4. Other
• Supports 13 MHz and 26 MHz Input Clocks
• 1.8V Typical Core Operating Voltages
• 289-Ball Package (12x12mm) , 0.65mm Ball pitch
5. The AD6720 baseband transmit section supports the following
• mobile station GMSK modulation power classes:
• GSM 900/850 power classes 4 and 5,
• DCS 1800 power classes 1 and 2, and
• PCS 1900 power classes 1 and 2