LG GT810h User manual

Date: May, 2009 / Issue 1.0
Service Manual Model : GT810h
Service Manual
GT810h
Internal Use Only

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1. INTRODUCTION .............................. 5
1.1 Purpose................................................... 5
1.2 Regulatory Information............................ 5
2. PERFORMANCE...............................7
2.1 System Overview .....................................7
2.2 Usable environment .................................8
2.3 Radio Performance ..................................9
2.4 Current Consumption.............................13
2.5 RSSI BAR ..............................................14
2.6 Battery BAR ...........................................14
3. TECHNICAL BRIEF ........................15
3.1 GENERAL DESCRIPTION ....................15
3.2 GSM MODE ...........................................17
3.3 UMTS MODE .........................................20
3.4 GPS MODE............................................23
3.5 LO GENERATION and
DISTRIBUTION CIRCUIT ......................24
3.6 OFF-CHIP RF COMPONENTS .............25
3.7 Digital Baseband(DBB/MSM7201A) ......30
3.8 Hardware Architecture ...........................32
3.9 Subsystem(MSM7201A) ........................34
3.10 Power Block.........................................37
3.11 External memory interface ...................42
3.12 H/W Sub System..................................44
3.13 Audio and sound..................................53
3.14 Camera interface .................................59
3.15 Proximity Sensor..................................65
3.16 Luminance Sensor...............................66
3.17 Motion Sensor......................................67
3.18 Main Features ......................................68
3.19 Main Component..................................69
4. TROUBLE SHOOTING ...................73
4.1 RF Component.......................................73
4.2 SIGNAL PATH .......................................75
4.3 Checking TCXO Block ...........................79
4.4 Checking Front End Module(FEM)Block81
4.5 Checking WCDMA Block .......................84
4.6 Checking GSM Block .............................96
4.7 Power ON Troubleshooting..................103
4.8 Charger Troubleshooting .....................105
4.9 USB trouble..........................................108
4.10 Audio trouble......................................111
4.11 3M Camera trouble ............................126
4.12 VGA Camera trouble..........................129
4.13 Main LCD trouble ...............................131
4.14 SIM Detect Troubleshooting ..............134
4.15 Keypad Backlight Troubleshooting ....136
4.16 LINEAR MOTOR................................138
4.17 Proximity Sensor on/off trouble..........140
4.18 Luminance Sensor on/off trouble.......142
4.19 Motion Sensor on/off trouble..............144
5. DOWNLOAD .................................146
5.1 Introduction ..........................................146
5.2 Downloading Procedure.......................146
6. BLOCK DIAGRAM ........................158
7. CIRCUIT DIAGRAM ......................169
8. BGA IC PIN CHECK......................177
9. PCB LAYOUT................................181
10. CALIBRATION & RF AUTO TEST
(HOT KIMCHI) .............................185
10.1 Usage of Hot-Kimchi ..........................185
11. TEST MODE ................................188
12. EXPLODED VIEW &
REPLACEMENT PART LIST ......195
12.1 EXPLODED VIEW .............................195
12.2 Replacement Parts
<Mechanic component>.....................197
<Main component> ............................200
12.3 Accessory ..........................................225
Table Of Contents
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Only for training and service purposes

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LGE Internal Use Only Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes

LGE Internal Use Only Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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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 phones or compatibility with the net
work, 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 the phones 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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Only for training and service purposes
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
A 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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Only for training and service purposes
2. PERFORMANCE
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2.1 System Overview
2. PERFORMANCE
400x240 / 176x144,
SXGA, VGA, QVGA, CIF, QCIFImage Sca
Video
ling Down
8. Main Camera
(3M)
15 fps at Full ResolutionFrame Rate
0.18mmPixel Pitch
400 x 240Dot
Progressive, <=X5
1600(H) X 1200(V) pixels. UXGA
CMOS image sensor
Typ. 300:1
Min. 40%, Typ. 50%
a-Si TFT, Trans missive
260,000
3 inch
Type
Resolution
Digital Zoom
Size
7. LCD
Color
Display Type
NTSC
Contrast Ratio
MSM7201A, RTR6285, PM75405. MSM Chipset
2Gb(Flash) / 1Gb(SDRAM) /User Memory : 100 MB6. Memory
1300mAh (Li-Polymer)4. Power
???g3. Weight
106.95x 55 x 13.95 (mm)2. Size
Bar Type1. Phone Type
Type / Spec.
4Mbps
Throughput
IEEE 802.11b/g
11. WLAN
300 mm (± 15° )10. Bluetooth
50 ~ 200m
Speaker/Receiver3) Receiver
18x12 oval type speaker2) Mono
72poly, SW MIDI1) MIDI
9. Audio

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2. PERFORMANCE
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2.2 Usable environment
1) Environment
2) Environment (Accessory)
Item Specification
Voltage 3.7 (Typ), 4.2 (Max)V
Operation Temp -20 ~ +60°C
Storage Temp -30 ~ +85°C
Humidity 65 % (Max)
Reference Spec.
TA Power AC 110 ~ 240V, 60Hz

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2. PERFORMANCE
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2.3 Radio Performance
1) Transmitter - GSM Mode
SpecificationItem
-98dBm/-96dBm (2.439%)
AM Suppression
-GSM : -31dBm - DCS : -29dBm
±0.5TTiming Advance
±800kHz, ±1600kHz
: -98dBm/-96dBm (2.439%)
Intermodulation rejection - Speech
channels
400kHz : -19dBm/-22dBm(5/0), -23dBm
600kHz : -21dBm/-24dBm(5/0), -26dBm
Spectrum due to switching transient
Class II(RBER) : -105dBm(2.439%)Reference Sensitivity - TCH/FS
0.012(-15 - -40dBm)Usable receiver input level range
GSM :
1800-3000kHz :< -63dBc(-46dBm)
3000kHz-6000kHz : <-65dBc(-46dBm)
6000kHz < : < -71dBc(-46dBm)
DCS :
1800-3000kHz :< -65dBc(-51dBm)
6000kHz < : < -73dBc(-51dBm)
Spectrum due to modulation out to larger
than 1800kHz offset to the edge of the
transmit band
200kHz : -36dBm
600kHz : -51dBm/-56dBm
Spectrum due to modulation out to less
than 1800kHz offset
<3.69usBurst Timing
GSM : 5dBm - 33dBm ± 3dB
DCS/PCS : 0dBm - 30dBm ± 3dB
Transmitter Output power and Burst
Timing
GSM/DCS : < -28dBm
EMC(Radiated Spurious Emission
Disturbance)
GSM : 0.1 ppm
DCS/PCS : 0.1 ppm
Frequency Error
RMS : 5°
Peak : 20 °
Phase Error

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2. PERFORMANCE
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2) Transmitter - WCDMA Mode
+24 dBm / 3.84 MHz, +1 / -3 dB
Maximum Output
Power
< -15 dB at Pout ≥ -20 dBm
Peak Code Domain
Error
< 17.5 %, when Pout ≥ -20 dBmError Vector Magnitude
< -31 dBc @ 5 MHz & < -41 dBc @ 10 MHz
when Interference CW Signal Level = -40 dBc
Transmit
Intermodulation
< -36 dBm / 1 kHz RW @ 9 kHz ≤ f < 150 kHz
< -36 dBm / 10 kHz RW @ 150 KHz ≤ f < 30 MHz
< -36 dBm / 100 kHz RW @ 30 MHz ≤ f < 1 GHz
< -30 dBm / 1 MHz RW @ 1 GHz ≤ f < 12.75 GHz
< -41 dBm / 300 kHz RW @ 1893.5 MHz < f < 1919.6 MHz
< -67 dBm / 100 kHz RW @ 925 MHz ≤ f ≤ 935 MHz
< -79 dBm / 100 kHz RW @ 935 MHz < f ≤ 960 GHz
< -71 dBm / 100 kHz RW @ 1805 MHz ≤ f ≤ 1880 MHz
Spurious Emissions
|f-fc| > 12.5 MHz
> 33 dB @ ± 5 MHz,
> 43 dB @ ± 10 MHz
Adjacent Channel
Leakage
Power Ratio (ACLR)
< 5 MHz at 3.84 Mcps (99% of power)
Occupied Bandwidth
< -50 dBm /3.84 MHz
Minimum Transmit
Power
Normal Conditions : within ± 9 dB,
Extreme Conditions : within ± 12 dB
Open Loop Power
Control
within ± 0.1 PPMFrequency Error
WCDMA850 : 824 MHz ~ 849 MHz
WCDMA1900 : 1850 ~1910 MHz
WCDMA2100 : 1920 MHz ~ 1980 MHz
Transmit Frequency
Spec if icat ion
Item

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2. PERFORMANCE
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3) Receiver - WCDMA Mode
< -57 dBm / 100 kHz BW @ 9 kHz ≤f < 1 GHz
< -47 dBm / 1 MHz BW @ 1 GHz ≤f ≤12.75 GHz
Spurious Emissions
Adjust output(TPC command)
cmd 1dB 2dB 3dB
+1 +0.5/1.5 +1/3 +1.5/4
0 -0.5/+0.5 -0.5/+0.5 -0.5/+0.5
-1 -0.5/-1.5 -1/-3 -1.5/-4
group(10equal command group)
+1 +8/+12 +16/+24
Inner Loop Power Control
In Uplink
BER < 0.001 when Œ
or= -103.7 dBm / 3.84 MHz
& Iouw1 = -46 dBm @ Fuw1(offset) = ±10 MHz
& Iouw2 = -46 dBm / 3.84 MHz @ Fuw2(offset) = ±20 MHz
Intermodulation
BER < 0.001 when Œ
or = -103.7 dBm / 3.84 MHz & Iblocking = -44 dBmSpurious Response
BER < 0.001 when Œ
or = -103.7 dBm / 3.84 MHz
& Iblocking = -56 dBm / 3.84 MHz @ Fuw(offset) = ±10 MHz
or Iblocking = -44 dBm / 3.84 MHz @ Fuw(offset) = ±15 MHz
Blocking Characteristic
ACS > 33 dB where BER < 0.001 when Œ
or = -92.7 dBm / 3.84 MHz
& Ioac = ñ52 dBm / 3.84 MHz @ ±5 MHz
Adjacent Channel
Selectivity (ACS)
BER < 0.001 when Œ
or = -25 dBm / 3.84 MHzMaximum Input Level
BER < 0.001 when Œ
or = -106.7 dBm / 3.84 MHzReference Sensitivity Level
WCDMA850 : 849 MHz ~ 894 MHz
WCDMA1900 : 1930 ~1990 MHz
WCDMA2100 : 2110 ~ 2170 MHz
Receive Frequency
Specification
Item

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2. PERFORMANCE
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4) Transmitter - HSDPA Mode
No Item Specification
1 Transmit Frequency 824 MHz ~ 849 MHz
1850MHz ~ 1910 MHz
1920 MHz ~ 1980 MHz
1Maximum Output Power Sub-Test
1=1/15, 2=12/15 21~25dBm / 3.84 MHz
3=13/15 4=15/8 20~25dBm / 3.84 MHz
5=15/7 6=15/0 19~25dBm / 3.84 MHz
Sub-test Power Start of Ack/Nack Power Transmitter
in table step boundary step power step
C.10.1.4 size, P tolerance
2HS-DPCCH [dB] [dB]
1Start of Ack/Nack 6 +/- 2.3
52Start of CQI 1 +/- 0.6
3Middle of CQI 0 +/- 0.6
4End of CQI 5 +/- 2.3
3Spectrum Emission Mask Sub-Test : 1=1/15, 2=12/15, 3=13/15,
4=15/8, 5=15/7, 6=15/0
Frequency offset Minimum Measurement
from carrier ∆f requirement Bandwidth
2.5 ~ 3.5 MHz -35-15(∆f-2.5)dBc 30 kHz
3.5 ~ 7.5 MHz -35-1(∆f-3.5)dBc 1 MHz
7.5 ~ 8.5 MHz -35-10(∆f-7.5)dBc 1 MHz
8.5 ~ 12.5 MHz -49dBc 1 MHz
4Adjacent Channel Leakage Sub-Test : 1=1/15, 2=12/15, 3=13/15,
Power Ratio (ACLR) 4=15/8, 5=15/7, 6=15/0
> 33 dB @ ±5 MHz
> 43 dB @ ±10 MHz
5Error Vector Magnitude 3GPP Not Complete

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2. PERFORMANCE
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5)Receiver - HSDPA Mode
2.4 Current Consumption
1) Current Consumption
(Stand by and Voice Call Test Condition : Bluetooth off, LCD backlight off,Neighbor Cell off) (VT Test
Condition : Speaker off, LCD backlight On)
No Item Specification
1 Receive Frequency 849 MHz ~ 894 MHz
1930 MHz ~1990 MHz
2110 ~ 2170 MHz
2Maximum Input Level Sub-Test : 1=1/15, 2=12/15, 3=13/15, 4=15/8, 5=15/7, 6=15/0
(BLER or R), 16QAM Only BLER < 10% or R >= 700kbps
Stand by Voice Call VT
Bluetooth Bluetooth
Off Connected
WCDMA
Under 3.00 mA Under 4.50 mA Under 250 mA N/A
(DRX=1.28) (DRX=1.28) (TX=12dBm low)
GSM Under 3.00 mA Under 4.50 mA Under 350 mA
Paging=5 period Paging=5 period (TX Power Level 5)

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2. PERFORMANCE
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2.5 RSSI BAR
2.6 Battery BAR
Indication Standby
Bar 4 →372%
Bar 3 →247%
Bar 2 →125%
Bar 1 →05%
Low Battery Alarm 15%
Critical Low Battery Alarm 5%
POWER OFF 0%
Level Change WCDMA GSM
BAR 4 → 3-82 ±2 dBm -91 ±2 dBm
BAR 3 → 2-92 ±2 dBm -96 ±2 dBm
BAR 2 → 1-102 ±2 dBm -101 ±2 dBm
BAR 1 → 0-112 ±2 dBm -106 ±2 dBm

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3. TECHNICAL BRIEF
3. TECHNICAL BRIEF
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3.1 GENERAL DESCRIPTION
The GT810h supports UMTS-850(Band V), UMTS-1900(Band I), UMTS-2100(Band I), GSM-850,
GSM-900, GSM-1800, and GSM-1900 based GSM/GPRS/EDGE/UMTS. All receivers and the UMTS
transmitter use the radioOne1Zero-IF architecture to eliminate intermediate frequencies, directly
converting signals between RF and baseband. The quad-band GSM transmitters use a baseband-to-
IF up-conversion followed by an offset phase-locked loop that translates the GMSK-modulated or 8-
PSK-modulated signal to RF.
[Fig. 3.1] Block diagram of RF part
1QUALCOMM’s branded chipset that implements a Zero-IF radio architecture.

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3. TECHNICAL BRIEF
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A generic, high-level functional block diagram of GT810h is shown in Figure 1-1. One antenna collects
base station forward link signals and radiates handset reverse link signals. The antenna connects with
receive and transmit paths through a D5015(FEM, Front End Module). The UMTS receive paths each
include an LNA, an RF band-pass filter, and a downconverter that translate the signal directly from RF-
to-baseband using radioOne ZIF techniques.
The RFIC’s RX analog baseband outputs, for the receive chains, connect to the MSM IC. The UMTS
and GSM RX baseband outputs share the same inputs to the MSM IC.
For the transmit chains, the RTR6285 IC directly translates the TX baseband signals (from the MSM
device) to an RF signal using an internal LO generated by integrated on-chip PLL and VCO. The
RTR6285 IC outputs deliver fairly high-level RF signals that are first filtered by TX SAWs and then
amplified by their respective UMTS PAs.
In the GSM receive path, the received RF signals are applied through their bandpass filters and down-
converted directly to baseband in the RTR6285 transceiver IC.
These baseband outputs are shared with the UMTS receiver and routed to the MSM IC for further
signal processing.
The GSM/EDGE transmit path employs one stage of up-conversion and, in order to improve efficiency,
is divided into phase and amplitude components to produce an open-loop Polar topology:
1. The on-chip quadrature up-converter translates the GMSK-modulated signal or 8- PSK
modulated signal, to a constant envelope phase signal at RF;
2. The amplitude-modulated (AM) component is applied to the ramping control pin of Polar power
amplifier from a DAC within the MSM.
GT810h power supply voltages are managed and regulated by the PM7540 Power Management IC.
This versatile device integrates all wireless handset power management, general housekeeping, and
user interface support functions into a single mixed signal IC. It monitors and controls the external
power source and coordinates battery recharging while maintaining the handset supply voltages using
low dropout, programmable regulators.
The device’s general housekeeping functions include an ADC and analog multiplexer circuit for
monitoring on-chip voltage sources, charging status, and current flow, as well as user-defined off-chip
variables such as temperature, RF output power, and battery ID. Various oscillator, clock, and counter
circuits support IC and higher-level handset functions. Key parameters such as under-voltage lockout
and crystal oscillator signal presence are monitored to protect against detrimental conditions.

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3. TECHNICAL BRIEF
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3.2 GSM MODE
3.2.1 GSM RECEIVER
The GSM-850, GSM-900, GSM-1800, and GSM-1900 receiver inputs of RTR6285 are connected
directly to the transceiver front-end circuits(filters and antenna switch module). GSM-850, GSM-900,
GSM-1800, and GSM-1900 receiver inputs use differential configurations to improve common-mode
rejection and second-order nonlinearity performance as shown in Figure 3-2. The balance between the
complementary signals is critical and must be maintained from the RF filter outputs all the way into the
IC pins.
[Figure 3-2] GSM Receiver Inputs Topologies

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3. TECHNICAL BRIEF
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Since GSM-850, GSM-900, GSM-1800, and GSM-1900 signals are time-division duplex (the handset
can only receive or transmit at one time), switches are used to separate RX and TX signals in place of
frequency duplexers - this is accomplished in the switch module. The GSM-850, GSM-900, GSM-1800,
and GSM-1900 receive signals are routed to the RTR6285 through band selection filters and matching
networks that transform single-ended 50-Ω sources to differential impedances optimized for gain and
noise figure. The RTR input uses a differential configuration to improve second-order inter-modulation
and common mode rejection performance.
The RTR6285 input stages include MSM-controlled gain adjustments that maximize receiver dynamic
range.
The amplifier outputs drive the RF ports of the quadrature RF-to-baseband downconverters. The
downconverted baseband outputs are multiplexed and routed to lowpass filters (one I and one Q)
having passband and stopband characteristics suitable for GMSK or 8-PSK processing. These filter
circuits include DC offset corrections. The filter outputs are buffered and passed on to the MSM6280 IC
for further processing as shown in Figure 3-4.

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3. TECHNICAL BRIEF
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3.2.2 GSM TRANSMITTER
The RTR6285 transmitter outputs(HB_RF_OUT1 and LB_RF_OUT1) include on-chip output matching
inductors. 50ohm output impedance is achieved by adding a series capacitor at the output pins. The
capacitor value may be optimized for specific applications and PCB characteristics based on pass-band
symmetry about the band center frequency as shown in Figure 3-3.
The RTR6285 IC is able to support GSM 900 and GSM 1800/1900 mode transmitting.
This design guideline shows a tri-band GSM application. Both high-band and low band outputs are
followed by resistive pads to ensure that the load presented to the outputs remains close to 50ohm.
[Figure 3-3] GSM Transmitter Outputs Topologies

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3. TECHNICAL BRIEF
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3.3 UMTS MODE
3.3.1 UMTS RECEIVER
The UMTS duplexer receiver output is routed to LNA circuits within the RTR6285 device as shown in
Figure .3-4. The UMTS RX input is provided with an on-chip LNA that amplifies the signal before a
second stage filter that provides differential downconverter as shown in Figure 1-5. This second stage
input is configured differentially to optimize second-order intermodulation and common mode rejection
performance. The gain of the UMTS front end amplifier and the UMTS second stage differential
amplifier are adjustable, under MSM control, to extend the dynamic range of the receivers. The second
stage UMTS RX amplifiers drive the RF ports of the quadrature RF-to-baseband downconverters. The
downconverted UMTS RX baseband outputs are routed to lowpass filters having passband and
stopband characteristics suitable for UMTS RX processing. These filter circuits allow DC offset
corrections, and their differential outputs are buffered to interface shared with GSM RX to the MSM IC.
The UMTS baseband outputs are turned off when the RTR6285 is downconverting GSM signals and on
when the UMTS is operating.
[Figure 3-4] UMTS Receiver Inputs Topologies

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3. TECHNICAL BRIEF
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3.3.2 UMTS TRANSMITTER
The UMTS TX path begins with differential baseband signals (I and Q) from the MSM device.
These analog input signals are amplified, filtered, and applied to the quadrature upconverter mixers.
The up-converter output is amplified by multiple variable gain stages that provide transmit AGC control.
The AGC output is filtered and applied to the driver amplifier; this output stage includes an integrated
matching inductor that simplifies the external matching network to a single series capacitor to achieve
the desired 50-Ω interface.
The RTR6285 UMTS output is routed to its power amplifier through a bandpass filter, and delivers fairly
high-level signals that are filtered and applied to the PA. Transmit power is delivered from the duplexer
to the antenna through the switch module.
The transceiver LO synthesizer is contained within the RTR6285 IC with the exception of the off-chip
loop filter components and the VC-TCXO. This provides a simplified design for multimode applications.
The PLL circuits include a reference divider, phase detector, charge pump, feedback divider, and digital
logic generator.
UMTS TX. Using only PLL1, the LO generation and distribution circuits create the necessary LO signals
for nine different frequency converters. The UMTS transmitter also employs the ZIF architecture to
translate the signal directly from baseband to RF.
This requires FLO to equal FRF, and the RTR6285 IC design achieves this without allowing FVCO to
equal FRF.
The RTR6285 IC is able to support UMTS 2100/1900/1800/1700 and 850 mode transmitting. This
design guideline shows only UMTS 2100 applications.