LG Renoir KC910 User manual

Date: October, 2008 / Issue 1.0
Service Manual Model : KC910
Service Manual
KC910
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......................................8
2.4 Current Consumption.................................15
2.5 RSSI BAR ..................................................16
2.6 Battery BAR ...............................................16
2.7 Sound Pressure Level ...............................17
2.8 Charging ....................................................18
3. TECHNICAL BRIEF............................19
3.1 GENERAL DESCRIPTION ........................19
3.2 GSM MODE...............................................21
3.3 UMTS MODE.............................................23
3.4 GPS MODE ...............................................26
3.5 LO GENERATION and DISTRIBUTION
CIRCUIT ....................................................27
3.6 OFF-CHIP RF COMPONENTS .................28
3.7 Digital Baseband (DBB/MSM6280) ...........37
3.8 Subsystem(MSM6280) ..............................40
3.9 Power Block...............................................49
3.10 External memory interface.......................55
3.11 H/W Sub System .....................................57
3.12 Feature List..............................................77
3.13 Multimedia Chip Interface ........................84
3.14 Touch Screen Interface ...........................91
3.15 Ambient Light Sensor Interface ...............92
3.16 Main features of KC910 ...........................93
3.16 Main Components of KC910....................94
4. TROUBLE SHOOTING.......................99
4.1 RF Component ..........................................99
4.2 SIGNAL PATH .........................................101
4.3 Checking TCXO Block .............................105
4.4 Checking Ant. Switch Module Block ........109
4.5 Checking UMTS Block.............................101
4.6 Checking GSM Block...............................124
4.7 WLAN/BT/FM Block.................................131
4.8 Power on trouble......................................137
4.9 SIM detect trouble....................................141
4.10 Key sense trouble ( KEYPAD ) ..............142
4.11 Keypad backlight trouble .......................145
4.12 Micro SD trouble ....................................147
4.13 Audio trouble..........................................148
4.14 Camera trouble ......................................163
4.15 Main LCD trouble...................................168
4.16 Touch Screen trouble ............................172
4.17 Ambient Light Sensor trouble ................173
5. DOWNLOAD.....................................174
5.1 Connecting to PC.....................................174
5.2 Select DZ Image Download mode ...........175
5.3 Choose Binary Image ..............................176
5.4 Choose the download style......................177
5.5 Start Downloading ...................................178
5.6 Check image downloading stateq............179
5.7 Finally Download Completed ...................180
6. BLOCK DIAGRAM ...........................181
1. System HW Block Diagram : Renoir Total
Block Diagram ...........................................181
2. System HW Block Diagram : RF Block......182
3. System HW Block Diagram (Detail) :
MEMORY...................................................184
7. CIRCUIT DIAGRAM..........................189
8. BGA IC PIN MAP..............................203
9. PCB LAYOUT ...................................207
10. Calibration......................................215
10.1 Usage of Hot-Kimchi..............................215
11. Test Mode .......................................218
12. EXPLODED VIEW & REPLACEMENT
PART LIST ..................................... 223
12.1 EXPLODED VIEW ................................ 223
122.2 Replacement Parts
<Mechanic component> ..................... 225
<Main component> ..............................229
12.3 Accessory ............................................. 255
Table Of Contents
LGE Internal Use Only Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes

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LGE Internal Use Only Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes

LGE Internal Use Only Copyright © 2007 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 commoncarrier 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

LGE Internal Use Only Copyright © 2007 LG Electronics. Inc. All right reserved.
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 antistatic 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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LGE Internal Use Only Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
2. PERFORMANCE
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2.1 System Overview
2. PERFORMANCE
Item Specification
Shape GSM900/1800/1900 and WCDMA Band1,8 Communicator Handset
Size 107.8 X 55.9 X 13.95 mm
Weight 110 g
Power 3.7V normal, 1000 mAh Li-Ion
Talk Time Over 170 min (WCDMA, Tx=10 dBm, Voice)
with 1000mAh) Over 200 min (GSM, Max Tx-29dBm, Voice)
Standby Time Over 250 Hrs (WCDMA, DRX=1.28)
(with 1000mAh) Over 250 Hrs (GSM, Paging period=5)
Antenna Internal type and Antenna
LCD TFT Main LCD(3’, 240 x 400)
LCD Backlight White LED Back Light
Camera 8.0 Mega pixel + VGA Video Call Camera
Vibrator Yes (Coin Type)
LED Indicator No
MIC Yes
Receiver Yes
Earphone Jack Yes
Connectivity Bluetooth, FM radio, Wi-Fi, GPS, USB
Volume Key Push Type (+, -)
External Memory Micro-SD
I/O Connect 18 Pin

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2.2 Usable environment
1) Environment
2) Environment (Accessory)
* CLA : 12 ~ 24 V(DC)
2.3 Radio Performance
1) Transmitter - GSM Mode
* In case of DCS : [A] -> 1710, [B] -> 1785 * In case of PCS : [A] -> 1850, [B] -> 1910
2. PERFORMANCE
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Item Specification
Voltage 3.7 V(Typ), 3.2 V(Min), [Shut Down : 3.2 V]
Operation Temp -20 ~ +60°C
Storage Temp -30 ~ +80°C
Humidity 85 % (Max)
Reference Spec. Min Typ. Max Unit
TA Power Available power 100 220 240 Vac
No Item GSM DCS & PCS
100k~1GHz -39dBm 9k ~ 1GHz -39dBm
MS allocated 1G~[A]MHz -33dBm
Channel 1G~12.75GHz -33dBm [A]M~[B]MHz -39dBm
Conducted [B]M~12.75GHz -33dBm
1Spurious 100k~880MHz -60dBm 100k~880MHz -60dBm
Emission 880M~915MHz -62dBm 880M~915MHz -62dBm
Idle Mode 915M~1GHz -60dBm 915M~1GHz -60dBm
1G~[A]MHz -50dBm 1G~[A]MHz -50dBm
[A]M~[B]MHz -56dBm [A]M~[B]MHz -56dBm
[B]M~12.5GHz -50dBm [B]M~12.5GHz -50dBm

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2. PERFORMANCE
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** In case of DCS : [A] -> 1710, [B] -> 1785 * In case of PCS : [A] -> 1850, [B] -> 1910
No Item GSM DCS & PCS
30M ~ 1GHz -36dBm 30M~1GHz -36dBm
MS allocated 1G~[A]MHz -30dBm
Channel 1G ~ 4GHz -30dBm [A]M~[B]MHz -36dBm
Radiated [B]M~4GHz -30dBm
2Spurious 30M ~ 880MHz -57dBm 30M~880MHz -57dBm
Emission 880M ~ 915MHz -59dBm 880M~915MHz -59dBm
Idle Mode 915M~1GHz -57dBm 915M~1GHz -57dBm
1G~[A]MHz -47dBm 1G~[A]MHz -47dBm
[A]M~[B]MHz -53dBm [A]M~[B]MHz -53dBm
[B]M~4GHz -47dBm [B]M~4GHz -47dBm
3Frequency Error ±0.1ppm ±0.1ppm
4Phase Error ±5(RMS) ±5(RMS)
±20(PEAK) ±20(PEAK)
3dB below reference sensitivity 3dB below reference sensitivity
Frequency Error RA250 : ±200Hz RA250: ±250Hz
5Under Multipath and HT100 : ±100Hz HT100: ±250Hz
Interference Condition TU50 : ±100Hz TU50: ±150Hz
TU3 : ±150Hz TU1.5: ±200Hz
0 ~ 100kHz +0.5dB 0 ~ 100kHz +0.5dB
200kHz -30dB 200kHz -30dB
250kHz -33dB 250kHz -33dB
Due to 400kHz -60dB 400kHz -60dB
Output RF modulation 600 ~ 1800kHz -66dB 600 ~ 1800kHz -60dB
61800 ~ 3000kHz -69dB 1800 ~ 6000kHz -65dB
Spectrum 3000 ~ 6000kHz -71dB ≥6000kHz -73dB
≥6000kHz -77dB
Due to 400kHz -19dB 400kHz -22dB
Switching 600kHz -21dB 600kHz -24dB
transient 1200kHz -21dB 1200kHz -24dB
1800kHz -24dB 1800kHz -27dB

LGE Internal Use Only Copyright © 2007 LG Electronics. Inc. All right reserved.
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2. PERFORMANCE
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No Item GSM DCS & PCS
Frequency offset 800kHz
7Intermodulation attenuation – Intermodulation product should
be Less than 55dB below the
level of Wanted signal
Power control Power Tolerance Power control Power Tolerance
Level (dBm) (dB) Level (dBm) (dB)
533±3 030±3
631±3 128±3
729±3 226±3
827±3 324±3
925±3 422±3
10 23 ±3 5 20 ±3
8Transmitter Output Power 11 21 ±3 6 18 ±3
12 19 ±3 7 16 ±3
13 17 ±3 8 14 ±3
14 15 ±3 9 12 ±4
15 13 ±3 10 10 ±4
16 11 ±5 11 8 ±4
17 9 ±5 12 6 ±4
18 7 ±5 13 4 ±4
19 5 ±5 14 2 ±5
15 0 ±5
9Burst timing Mask IN Mask IN

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2. PERFORMANCE
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2) Transmitter - WCDMA Mode
No Item Specification
1Transmit Frequency Band1 : 1920 ~1980 MHz
Band8 : 880~ 915 MHz
2Maximum Output Power Class 3 : +24dBm(+1/-3dB)
Class 4 : +21dBm(°æ2dB)
3Frequency Error ±0.1ppm
4Open Loop Power Control in Uplink ±9dB@normal, ±12dB@extreme
Adjust output(TPC command)
cmd 1dB 2dB 3dB
+1 +0.5/1.5 +1/3 +1.5/4.5
5Inner Loop Power Control in Uplink 0 -0.5/+0.5 -0.5/+0.5 -0.5/+0.5
-1 -0.5/-1.5 -1/-3 -1.5/-4.5
Group(10 equel command group)
+1 +8/+12 +16/+24
6Minimum Output Power -50dBm(3.84MHz)
Qin/Qout : PCCH quality levels
7Out-of-synchronization handling of output power Toff@DPCCH/Ior : -22 -> -28dB
Ton@DPCCH/Ior : -24 -> -18dB
8Transmit OFF Power -56dBm(3.84MHz)
9Transmit ON/OFF Time Mask ±25us
PRACH,CPCH,uplinlk compressed mode
±25us
10 Change of TFC Power varies according to the data rate
DTX : DPCH off
(minimize interference between UE)
11 Power setting in uplink compressed ±3dB(after 14slots transmission gap)
12 Occupied Bandwidth(OBW) 5MHz(99%)
-35-15*(∆f-2.5)dBc@∆f=2.5~3.5MHz,30k
13 Spectrum emission Mask
-35-1*(∆f-3.5)dBc@∆f=3.5~7.5MHz,1M
-39-10*(∆f-7.5)dBc@∆f=7.5~8.5MHz,1M
-49dBc@∆f=8.5~12.5MHz,1M

LGE Internal Use Only Copyright © 2007 LG Electronics. Inc. All right reserved.
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3)Receiver - GSM Mode
2. PERFORMANCE
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No Item Specification
14 Adjacent Channel Leakage Ratio(ACLR) 33dB@5MHz, ACP>-50dBm
43dB@10MHz, ACP>-50dBm
-36dBm@f=9~150KHz, 1K BW
-36dBm@f=50KHz~30MHz, 10K BW
-36dBm@f=30MHz~1000MHz, 100K BW
15 Spurious Emissions -30dBm@f=1~12.5GHz, 1M BW
(*: additional requirement) (*)-41dBm@f=1893.5~1919.6MHz, 300K
(*)-67dBm@f=925~935MHz, 100K BW
(*)-79dBm@f=935~960MHz, 100K BW
(*)-71dBm@f=1805~1880MHz, 100K BW
16 Transmit Intermodulation -31dBc@5MHz,Interferer -40dBc
-41dBc@10MHz, Interferer -40dBc
17 Error Vector Magnitude (EVM) 17.5%(>-20dBm)
(@12.2K, 1DPDCH+1DPCCH)
18 Transmit OFF Power -15dB@SF=4.768Kbps, Multi-code
transmission
No Item GSM DCS & PCS
1 Sensitivity (TCH/FS Class II) -105dBm -105dBm
2
Co-Channel Rejection C/Ic=7dB Storage -30 ~ +85
(TCH/FS Class II, RBER, TU high/FH)
3Adjacent Channel 200kHz C/Ia1=-12dB C/Ia1=-12dB
Rejection 400kHz C/Ia2=-44dB C/Ia2=-44dB
Wanted Signal :-98dBm Wanted Signal :-96dBm
4 Intermodulation Rejection 1st interferer:-44dBm 1st interferer:-44dBm
2nd interferer:-45dBm 2nd interferer:-44dBm
5Blocking Response Wanted Signal :-101dBm Wanted Signal :-101dBm
(TCH/FS Class II, RBER) Unwanted : Depend on Frequency Unwanted : Depend on Frequency

LGE Internal Use Only Copyright © 2007 LG Electronics. Inc. All right reserved.
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2. PERFORMANCE
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4) Receiver - WCDMA Mode
No Item Specification
1Reference Sensitivity Level -Band 1(2110~2170MHz) : -106.7 dBm(3.84 MHz)
-Band 8(925~960MHz) : -103.7 dBm(3.84 MHz)
-25dBm(3.84MHz)
2Maximum Input Level -44dBm/3.84MHz(DPCH_Ec)
UE@+20dBm output power(Class3)
3Adjacent Channel Selectivity (ACS) 33dB
UE@+20dBm output power(Class3)
-56dBm/3.84MHz@10MHz
4In-band Blocking UE@+20dBm output power(Class3)
-44dBm/3.84MHz@15MHz
UE@+20dBm output power(Class3)
-44dBm/3.84MHz@f=2050~2095 and
2185~2230MHz
UE@+20dBm output power(Class3)
-30dBm/3.84MHz@f=2025~2050 and
5Out-band Blocking 2230~2255MHz
UE@+20dBm output power(Class3)
-15dBm/3.84MHz@f=1~2025 and
2255~12500MHz
UE@+20dBm output power(Class3)
6Spurious Response -44dBm CW
UE@+20dBm output power(Class3)
-46dBm CW@10MHz
7Intermodulation Characteristic -46dBm/3.84MHz@20MHz
UE@+20dBm output power(Class3)
-57dBm@f=9KHz~1GHz, 100K BW
8Spurious Emissions -47dBm@f=1~12.5GHz, 1M BW
-60dBm@f=1920MHz~1980MHz, 3.84M BW
-60dBm@f=2110MHz~2170MHz, 3.84M BW

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2. PERFORMANCE
5) Transmitter - WCDMA(HSDPA) Mode
6) Receiver - WCDMA(HSDPA) Mode
LGE Internal Use Only Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
No Item Specification
1Transmit Frequency -Band 1 : 1920~1980MHz
-Band 8 : 880~915MHz
2Maximum 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
3HS-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
4Spectrum 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
6Adjacent 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
6Error Vector Magnitude < 17.5 %, when Pout ≥ -20 dBm

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2. PERFORMANCE
LGE Internal Use Only Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
6) Receiver - WCDMA(HSDPA) Mode
2.4 Current Consumption
(Stand by Test Condition : Bluetooth off, LCD backlight off)
(Call Test Condition : Bluetooth off, LCD backlight off)
(VT Test Condition : Speaker off, LCD backlight On)
No Item Specification
1Receiver Frequency -Band 1 : 2110~2170MHz
-Band 8 : 925~960MHz
2Maximum Input Level Sub-Test : 1=1/15, 2=12/15, 3=13/15,
(BLER or R), 16QAM Only 4=15/8, 5=15/7, 6=15/0
BLER < 10% or R >= 700kbps
Stand by Voice Call VT
WCDMA
4.7 mA ↓435 mA ↓683mA ↓
(DRX=1.28) (Tx=12dBm) (Tx=12dBm)
3.2 mA ↓435 mA ↓
GSM (Paging=9period) (Tx=Max)

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2.5 RSSI BAR
2.6 Battery BAR
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Only for training and service purposes
Indication Standby
Bar 3 3.79 ±0.05V ↑
Bar 3 →23.78 ±0.05V
Bar 2 →13.68 ±0.05V
Bar 1 →Empty 3.50 ±0.05V
Low Voltage, 3.50 ±0.05V
Warning message+ Blinking [Interval : 3min(Stand-by) / 1min(Talk)]
Power Off 3.20 ±0.05V(Stand-by)
3.20 ± 0.05V(Talk)
Level Change WCDMA GSM
7 → 5-91 ±2dBm -93 ±2dBm
5 → 4-104 ±2dBm -98 ±2dBm
4 → 2-108 ±2dBm -101 ±2dBm
2 → 1-110 ±2dBm -104 ±2dBm
1 → 0-112 ±2dBm -106 ±2dBm

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2.7 Sound Pressure Level
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Only for training and service purposes
Under -40 dBPAMax
-4 ± 3 dBNor
Receiving Loudness Rating (RLR)2
-15 ± 3 dBMax
-62 dBmMax
MS and
Headset
TDMA Noise
-. GSM : Power Level : 5
DCS/PCS : Power Level : 0
(Cell Power : -90 ~ -105 dBm)
-. Acoustic (Max Vol.)
MS/Headset SLR : 8 ± 3dB
MS/Headset RLR : -15 ± 3dB / -12dB
(SLR/RLR : Mid-value setting)
17
Under -45 dBPANor
Idle Noise-Receiving (INR)16
-55 dBm0pMaxIdle Noise-Sending (INS)15
Refer to Table 30.4Receiving Distortion (RD)14
Refer to Table 30.3Sending Distortion (SD)13
40 dBMinEcho Loss (EL)12
25 dBMinSide Tone Masking Rating (STMR)11
-12 ± 3 dBMax
-1 ± 3 dBNor
Receiving Loudness Rating (RLR)10
8 ± 3 dB
Headset
Sending Loudness Rating (SLR)9
Under -36 dBPAMax
Under -47 dBPANor
Idle Noise-Receiving (INR)8
-64 dBm0pMaxIdle Noise-Sending (INS)7
Refer to Table 30.4Receiving Distortion (RD)6
Refer to Table 30.3Sending Distortion (SD)5
40 dBMinEcho Loss (EL)4
17 dBMinSide Tone Masking Rating (STMR)3
8 ± 3 dB
MS
Sending Loudness Rating (SLR)1
SpecificationTest Item
No

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2. PERFORMANCE
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2.8 Charging
• Charging Method : CC & CV (Constant Current & Constant Voltage)
• Maximum Charging Voltage : 4.2V
• Maximum Charging Current : 600mA
• Nominal Battery Capacity : 1000 mAh
• Charger Voltage : 5.1V
• Charging time : Max 3 h (Except time trickle charging)
• Full charge indication current (icon stop current) : 80mA
• Low battery POP UP : 3.5V
• Low battery alarm interval : Idle - 3 min, Dedicated - 1min
• Cut-off voltage : 3.2V

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Only for training and service purposes
3. TECHNICAL BRIEF
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3.1 GENERAL DESCRIPTION
The KC910 supports UMTS-900, UMTS-2100, 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 upconversion followed by an offset
phase-locked loop that translates the GMSK-modulated or 8-PSK-modulated signal to RF.
1QUALCOMM’s branded chipset that implements a Zero-IF radio architecture.
3. TECHNICAL BRIEF
MSM6280
[W-PAM]
RF5184
RTR_TXIP//TXIM,
RTR_TXQP//TXQM
[GSM PAM]
TQM7M5012
DCS_PCS_TX
EGSM_TX
RTR6285
3
[FEM]
D5015
Epcos
DCS_PCS_TX
EGSM/DCS/PCS RX
Coupler
(20dB)
EGSM_TX
WB_MX_INP
WPRXSE2_OUT
W2100_TX
RTR_RXIP//RXIM,
RTR_RXQP//RXQM I_IP_CH0
I_IM_CH0
Q_IP_CH0
Q_IM_CH0
I_OUT_P
I_OUT_N
Q_OUT_P
Q_OUT_N
Rx_WCDMA_2100 WPRXSE2
WB_MX_INM
SSBDT_RTR
RTR_TX_ON
RF_ON
PDET_IN
RTR_DRXIP//DRXIM,
RTR_DRXQP//DRXQM I_IP_CH1
I_IM_CH1
Q_IP_CH1
Q_IM_CH1
[LNA Module] GPS_IN
HB_RF_OUT3
LB_RF_OUT2
SAYZ1G95EA0B00
B7681
Coupler
(20dB)
Rx_WCDMA_900
W900_TX
PM6658
Input Power
Management
Voltage
Regulators
General
Housekeeping
User
Interfaces
IC
Interfaces
RTR6285_TCXO
MSM_TCXO
VCTCXO
(19.2MHz)
[Figure 1-1] Block diagram of RF part

LGE Internal Use Only Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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 band-pass 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
KC910 power supply voltages are managed and regulated by the PM6658 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 userdefined 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.
3. TECHNICAL BRIEF
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LGE Internal Use Only Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
3. TECHNICAL BRIEF
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3.2 GSM MODE
3.2.1 GSM RECEIVER
The GSM-900, GSM-1800, and GSM-1900 receiver inputs of RTR6285 are connected directly to the
transceiver front-end Module. GSM-900, GSM-1800, and GSM-1900 receiver inputs use differential
configurations to improve common-mode rejection and second-order non-linearity performance as
shown in Figure 1-2. 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 1-2] GSM Receiver Inputs Topologies