LG G7100 User manual

Table Of Contents
1. INTRODUCTION................................…5
1.1 Purpose ............................................….
1.2 Regulatory Information ..........................
1.3 Abbreviations .........................................
2. PERFORMANCE ..............................….9
2.1 H/W Feature .....................................…..
2.2 Technical Specification ..........................
3. TECHNICAL BRIEF ............................16
3.1 General Description of RF parts ......…..
3.2 Receiver Part ...................................….
3.3 Synthesizer Part …………………………
3.4 Transmitter Part ................................….
3.5 13 MHz Clock ...................................….
3.6 Power Supplies and Control Signals .….
3.7 Digital Main Processor ......................….
3.8 Analog Main Processor ......................…
3.9 Power Management IC .....................….
3.10 Memories ........................................... .
3.11 Display and Interface ......................... .
3.12 Keypad Switches and Scanning ........ .
3.13 Microphone ........................................ .
3.14 Earpiece .....................…………………
3.15 Hands-free Interface …………………..
3.16 Headset Jack Interface ...................….
3.17 Key Back-light Illumination ..............….
3.18 LCD Back-light Illumination ……………
3.19 Speaker & MIDI IC ..........................….
3.20 CAMERA IC …………………………….
4. TROUBLE SHOOTING ................… 53
4.1 RF Components .............................….
4.2 Rx Trouble ..........................................
4.3 Tx Trouble ..........................................
4.4 Power On Trouble ..........................….
4.5 Charging Trouble ...........................….
4.6 LCD Trouble .......................................
4.7 Receiver Trouble ................................
4.8 Speaker Trouble .................................
4.9 MIC Trouble ...................................….
4.10 Vibrator Trouble ...............................
4.11 Key Backlight LED Trouble ..............
4.12 Folder on/off Trouble ………………..
4.13 SIM Detect Trouble ..........................
4.14 Earphone Trouble ............................
4.15 HFK Trouble .....................................
4.16 CAMERA Trouble ……………………
5. DISASSEMBLY INSTRUCTION .... 110
5.1 Disassembly .......................................
6. DOWNLOAD AND
CALIBRATION ................................ 118
6.1 Download ......................................…..
6.2 Calibration .....................................…..
7. BLOCK DIAGRAM ........................... 128
5
5
7
9
11
16
16
19
20
23
24
25
30
36
39
40
40
42
43
43
43
46
47
48
49
53
54
63
73
76
78
80
82
84
87
89
91
93
95
100
106
110
118
125
-3 -

9. PCB LAYOUT .................................. 135
10. ENGINEERING MODE .................. 137
10.1 BB Test [MENU 1] .....................……
10.2 RF Test [MENU 2] .....................……
10.3 MF mode [MENU 3] ...................……
10.4 Trace option [MENU 4] ..............……
10.5 Call timer [MENU 5] ..................……
10.6 Fact. Reset [MENU 6] ................……
10.7 S/W version [MENU 7] ...............……
11. STAND ALONE TEST ................... 143
11.1 Introduction ................................……
11.2 Setting Method ..........................……
11.3 Means of Test ............................……
12. AUTO CALIBRATION ................... 146
12.1 Overview ....................................……
12.2 Requirements ............................……
12.3 Menu and Settings ........................…
12.4 AGC …………………………………..
12.5 APC …………………………………...
12.6 ADC ……………………………………
12.7 Setting …………………………………
12.8 How to do calibration .................……
13. EXPLODED VIEW &
REPLACEMENT PART LIST ...…. 149
13.1 Exploded View ...........................……
13.2 Accessory ...............................……..
13.3 Replacement Parts
< Mechanic component > ……………..
Replacement Parts
< Main component > ………………….
138
140
141
142
142
142
142
143
143
144
146
146
146
148
148
148
148
148
149
151
152
155
-4 -
8. CIRCUIT DIAGRAM ......................... 129
8.1 MAIN .............................................…..
8.2 Memory & MMI & PMIC ..........……….
8.3 MMI …............................................….
8.4 Audio ………..................................…..
8.5 Camera ……………………..………….
8.6 RF Circuit ………………………………
129
130
131
132
133
134

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
-5 -

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
-6-

1.3 Abbreviations
For the purposes of this manual, following abbreviations apply:
Offset Phase Locked LoopOPLL
Light Emitting DiodeLED
Low Drop OutputLDO
Liquid Crystal DisplayLCD
Intermediate FrequencyIF
International Portable User IdentityIPUI
Global System for Mobile CommunicationsGSM
General Purpose Interface BusGPIB
Gaussian Minimum Shift KeyingGMSK
Flexible Printed Circuit BoardFPCB
Electrostatic DischargeESD
Electrical Erasable Programmable Read-Only MemoryEEPROM
Digital Signal ProcessingDSP
dB relative to 1 milli wattdBm
Digital Communication SystemDCS
Digital to Analog ConverterDAC
Constant Current – Constant VoltageCC-CV
Bit Error RatioBER
BasebandBB
Automatic Power ControlAPC
-7-
1. INTRODUCTION

Wireless Application ProtocolWAP
Voltage Control Temperature Compensated Crystal OscillatorVCTCXO
Voltage Controlled OscillatorVCO
Universal Asynchronous Receiver/TransmitterUART
Time Division Multiple AccessTDMA
Time Division DuplexTDD
Travel AdapterTA
Side Tone Masking RatingSTMR
Pseudo SRAMPSRAM
Static Random Access MemorySRAM
Sending Loudness RatingSLR
Subscriber Identity ModuleSIM
Surface Acoustic WaveSAW
Real Time ClockRTC
Root Mean SquareRMS
Receiving Loudness RatingRLR
Radio FrequencyRF
Public Switched Telephone NetworkPSTN
Phase Locked LoopPLL
Programmable Gain AmplifierPGA
Printed Circuit BoardPCB
Power Amplifier ModulePAM
-8-
1. INTRODUCTION

2. PERFORMANCE
2.1 H/W Features
Item Feature Comment
Standard Battery
Li-ion, 770 mAh
Size: 35 ×62 ×3.8mm
Weight: 16g
Stand by Current
Under the minimum current consumption environment
(such as paging period 9), the level of standby current
is below 4mA.
Talk time Up to 3hours (GSM TX Level 7)
Stand by time Up to 200hours (Paging Period: 9, RSSI: -85 dBm)
Charging time Standard charge: 5hours
Rapid charge: Approx. 2.5hours
RX Sensitivity GSM, EGSM: -105dBm, DCS: -105dBm
TX output power GSM, EGSM: 33dBm(Level 5),
DCS: 30dBm(Level 0)
SIM card type 3V Small
Display Main LCD: 128 ×160 pixel 65K Color
Sub LCD: 96 ×64 pixel 256 Color
Status Indicator
Hard icons. Key Pad
0 ~ 9, #, *, Up/Down Navigation Key
Confirm Key, Clear Key
Send Key, END/PWR Key
ANT External
EAR Phone Jack Yes
PC Synchronization Yes
Speech coding EFR/FR/HR
Data and Fax Yes
2. PERFORMANCE
GPRS compatibility Class 10
Vibrator Yes
Loud Speaker Yes
Voice Recoding Yes
C-Mike Yes
-9-

Travel Adapter Yes
Options Hands-free kit, CLA, Data Kit
Receiver Yes
Camera VGA 640 ×320 pixel
MIDI 32 Poly
Item Feature Comment
2. PERFORMANCE
- 10 -

2.2 Technical Specification
Item Description Specification
1Frequency Band
GSM
TX: 890 + n × 0.2 MHz
RX: 935 + n × 0.2 MHz (n=1~124)
EGSM
TX: 890 + (n-1024) × 0.2 MHz
RX: 935 + (n-1024) × 0.2 MHz (n=975~1024)
DCS
TX: 1710 + (n-512) × 0.2 MHz
RX: 1805 + (n-512) × 0.2 MHz (n=512~885)
2Phase Error RMS < 5 degrees
Peak < 20 degrees
3Frequency Error < 0.1 ppm
4Power Level
Level Power Toler. Level Power Toler.
6 31dBm ±3dB 14 15dBm ± 3dB
7 29dBm ±3dB 15 13dBm ± 3dB
8 27dBm ±3dB 16 11dBm ± 5dB
9 25dBm ±3dB 17 9dBm ± 5dB
10 23dBm ±3dB 18 7dBm ± 5dB
11 21dBm ±3dB 19 5dBm ± 5dB
12 19dBm ±3dB
GSM, EGSM
5 33dBm ±2dB 13 17dBm ± 3dB
Level Power Toler. Level Power Toler.
1 28dBm ±3dB 9 12dBm ± 4dB
2 26dBm ±3dB 10 10dBm ± 4dB
3 24dBm ±3dB 11 8dBm ± 4dB
4 22dBm ±3dB 12 6dBm ± 4dB
5 20dBm ±3dB 13 4dBm ± 4dB
6 18dBm ±3dB 14 2dBm ± 5dB
7 16dBm ±3dB 15 0dBm ± 5dB
DCS
0 30dBm ±2dB 8 14dBm ± 3dB
- 11 -
2. PERFORMANCE

5Output RF Spectrum
(due to modulation)
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
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 -65
3,000~ <6,000 -65
6,000 -73
DCS
6
Output RF Spectrum
(due to switching
transient)
GSM, EGSM
Offset from Carrier (kHz). Max. dBm
400 -19
600 -21
1,200 -21
1,800 -24
- 12 -
Item Description Specification
2. PERFORMANCE

Item Description Specification
6
Output RF Spectrum
(due to switching
transient)
Offset from Carrier (kHz). Max. dBm
400 -22
600 -24
1,200 -24
1,800 -27
7Spurious Emissions Conduction, Emission Status
8 Bit Error Ratio
GSM, EGSM
BER (Class II) < 2.439% @-102 dBm
DCS
BER (Class II) < 2.439% @-100 dBm
9RX Level Report Accuracy ±3 dB
10 SLR 8±3 dB
11 Sending Response
300 -12
1,000 -6
2,000 -6
3,000 -6
Frequency (Hz) Max.(dB) Min.(dB)
100 -
200 -
4,000 -
3,400 -9
0
0
4
4
-12
0
0
4
12 RLR 2±3 dB
DCS
- 13 -
2. PERFORMANCE

Item Description Specification
13 Receiving Response
300 -7
500 -5
1,000 -5
3,000 -5
Frequency (Hz) Max.(dB) Min.(dB)
100 -
200 -
4,000
3,400 -10
2
*
0
2
-12
0
2
2
14 STMR 13±5 dB
* Mean that Adopt a straight line in between 300 Hz
and 1,000 Hz to be Max. level in the range.
15 Stability Margin > 6 dB
-20
-10
0
7
dB to ARL (dB) Level Ratio (dB)
-35
-30
10
30.7
33.3
33.7
31.7
17.5
22.5
25.5
16 Distortion
17 Side Tone Distortion Three stage distortion < 10%
18 System frequency
(13 MHz) tolerance ≤ 2.5 ppm
19 32.768KHz tolerance ≤ 30 ppm
20 Ringer Volume
At least 80 dB under below conditions:
1. Ringer set as ringer.
2. Test distance set as 50 cm
- 14 -
2. PERFORMANCE

Item Description Specification
21 Charge Current Fast Charge : < 500 mA
Slow Charge : < 60 mA
3
2
1
0
Antenna Bar Number Power
5
4
-95 dBm ~ -91 dBm
-100 dBm ~ -96 dBm
-105 dBm ~ -101 dBm
~ -105 dBm
-85 dBm ~
-90 dBm ~ -86 dBm
22 Antenna Display
2
3
Battery Bar Number Voltage
0
1
3.73 ~ 3.82 V
3.82 V ~
~ 3.62 V
3.62 ~ 3.73 V
23 Battery Indicator
24 Low Voltage Warning
3.62 ± 0.03V (Call)
3.5 ± 0.03V (Standby)
25 Forced shut down
Voltage 3.35 ± 0.03V
26 Battery Type
1 Li-ion Battery
Standard Voltage = 3.8 V
Battery full charge voltage = 4.2 V
Capacity: 770mAh
27 Travel Charger
Switching-mode charger
Input: 100 ~ 240 V, 50/60 Hz
Output: 5.2 V, 600 mA
- 15 -
2. PERFORMANCE

3.1 General Description of RF parts
The RF parts consists of a transmitter part,a receiver part,a synthesizer part,a voltage supply part,a
VCTCXO part. And the main RF Chipset CX74017[U603]is a single-chip dual-band transceiver for the
extended global system for mobile communication[E-GSM900MHz]/
Digital communication system[DCS1800MHz] voice and data transfer applications.
This device integrated a direct conversion receiver architecture, a transmitter based on a modulation loop
architecture and fractional-N synthesizer part with built in TXVCO and Local-VCO.
3.2 Receiver Part
The Receiver part in CX74017 contains all active circuits completely, full receiver chain with the
exception of discrete front-end RF SAW filters. The filtered and amplified signal is down converted in
the RF-mixer to the baseband output. The receiver path is supported by internal channel filtering.
ANT
S/W
U603(CX74017)
Base
Band
Block
DCS : 1805 ~ 1880MHz
GSM : 925 ~ 960MHz
90
0
90
0
RXIP
RXIN
RXQP
RXQN
U405(SHS-M090B)
U408(SAFSE942MAL)
U407(SAFSE1G84KA)
LO
VGA1 VGA2
DCOC
DCOC DCOC
DCOC DCOC DCOC
VGA1 VGA2
Figure. 3-1 Receiver Block diagram
3. TECHNICAL BRIEF
3. TECHNICAL BRIEF
- 16 -

A. RF Front End
RF front end consists of Antenna Switch(FL405), an integrated two saw filters,(FL601),dual band
LNAs integrated in transceiver.
The Received RF signals(GSM 925MHz ~ 960MHz, DCS 1805MHz ~ 1880MHz) are fed into the
antenna or Mobile switch. An antenna matching circuit is between the antenna and the mobile
switch. The Antenna Switch(FL600) is used to control the Rx and Tx paths. And, the input signals
VC1 and VC2 of a FL600 are directly connected to baseband controller to switch either Tx or Rx
path on. Ant S/W module(FL600) is an antenna switch module for dual band phone.
The logic and current is given below table 3-1.
Table 3-1 The logic and current
<0.1 mA0 V0 VGSM/DCS RX
10.0 mA max0 V2.5 to 3 VDCS TX
10.0 mA max2.5 to 3 V0 VGSM TX
CurrentVC2VC1
The receiver part uses a low-IF receiver architecture that allows for the on-chip integration
of the channel selection filters, eliminating the external RF image reject filters and the IF
SAW filter required in conventional super-heterodyne architecture. The Receive part of
CX74017 integrates three differential input LNAs that are matched to the 200 Ohm
balanced-output SAW filters through external LC matching networks.
3. TECHNICAL BRIEF
- 17 -

In direct conversion receiver there is only one mixer down-converting received RF signal to BB signal
directly. The gain down converting mixer is 40dB at high gain mode and 22dB at low gain mode.
The Rx gain setting is done in the AGC algorithm. The nominal gain of the receiver is set as a
function of the expected signal strength at the antenna input so that a desired level is reached at the
Rx I/Q. 7 blocks in the receiver chain have variable gains, LNA, Mixer, LPF1, VGA1, gmC Filter,
Auxiliary gain control and VGA2. The gain settings can be adjustable via 3-wire bus control lines.
The baseband signals pass via integrated low-pass filters to the baseband A/D converters.
Theremainder of the channel filtering is performed by the baseband chipset. The demodulator
contains switches to maintain the sense of the baseband I/Q outputs with respect to the incoming RF
signal on both GSM900 and DCS1800.
Three correction loops ensure that DC offsets, generated in the CX74017, do not overload the
baseband chain at any point.
After compensation, the correction voltages are held on capacitors for the duration of the
receive slot(s). A rising edge on the RXEN signal, selected via the serial interface, placed the
DC compensation circuitry in the track mode.
B. Demodulator and baseband processing
C. DC offset compensation
- 18 -
3. TECHNICAL BRIEF

3.3 Synthesizer Part
GSM
REFCLK
CX74017
Base
Band
Block
13MHz
Fractional-N
PLL
X2
DCS
/R
f vco = (N+3.5+FN/2^22) f ref/R
f vco
f ref
/3
LF
f LO
AFC
13MHz
2V7_VTCXO
GSM DCS
4/3 2/3
Figure.3-2 Synthesizer Block diagram
The CX74017 includes a fully integrated UHF VCO with an on-chip LC tank.
A single sigma-delta fractional-N synthesizer can phase lock the local osillator used in both
transmit and receive path to a precision frequency reference input. Fractional-N operation offers
low phase noise and fast setting times, allowing for multiple slot applications such as GPRS.
The counter and mode settings of the synthesizer are also programmed via 3-wire interface.
- 19 -
3. TECHNICAL BRIEF

The Transmitter part contains CX74017 active parts, PAM and Antenna Switch.
The CX74017 active part consists of a vector modulator and offset phase-locked loop block(OPLL)
including down-converter, phase detector, loop filter and dual band transmit VCO which can operate
at either final RF output frequency. The RF GMSK outputs from the transmit VCO are fed directly to
the RF power amplifiers. The peak output power and the profile of the transmitted burst are
controlled by means of a closed feedback loop. A dual band directional coupler is used to sample the
RF output from either PA. The PA outputs from the directional coupler pass to the antenna connector
via Antenna Switch.
Figure 3-3. RF Transmitter path Block Diagram
ANT
S/W
TXVCO
U601(CX77315))
Base
Band
Block
DCS : 1710 ~ 1785MHz
GSM : 880 ~ 925MHz
90
0
LF
TXIP
TXIN
TXQP
TXQN
PFD
/D2
/D1
X2
fTX
fIF
fLO
TXRAMP TXPA
FL600(LMSP54AA-097)
LO
BANDSEL1
3.4 Transmitter Part
- 20 -
3. TECHNICAL BRIEF

The baseband converter(BBC) within the GSM chipset generates I and Q baseband signals for the
transmit vector modulator. The modulator provides more than 40dBc of carrier and unwanted side-
band rejection and produces a GMSK modulated signal. The baseband software is able to cancel out
differential DC offsets in the I/Q baseband signals caused by imperfections in the D/A converters.
The TX-Modulator implements a quadrature modulator. The IF-frequency input signal is split into two
precise orthogonal carriers, which are multiplied by the baseband modulation signal IT/ITX and
QT/QTX. It is used as reference signal for the OPLL.
A. IF Modulator
The offset mixer down converts the feedback Tx RF signal using LO to generate a IF modulating
signal. The IF signal goes via external passive bandpass filter to one port of the phase detector.
The other side of the phase detector input is LO signal. The phase detector generates an error
current proportional to the phase difference between the modulated signal from the offset mixer
and the reference signal from the LO. The error current is filtered by a second order low-pass filter
to generate an output voltage which depends on the GMSK modulation and the desired channel
frequency. This voltage controls the transmit VCO such that the VCO output signal, centered on
the correct RF channel, is frequency modulated with the original GMSK data. The OPLL acts as a
tracking narrowband band pass filter tuned to the desired channel frequency. This reduces the
wideband noise floor of the modulation and up-conversion process and provides significant
filtering of spurious products.
B. OPLL
The CX77315[U601] is designed in a 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, impedance-matching circuitry for 50 ohm input and output
impedances, and a Power Amplifier Control (PAC) block with and internal current-sense resistor.
C. Power amplifier
- 21 -
3. TECHNICAL BRIEF

Figure 3-4. Power Amplifier Block Diagram
- 22 -
3. TECHNICAL BRIEF