LG KT610 User manual

Date: June, 2008 / Issue 1.0
Service Manual Model : KT610
Service Manual
KT610
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.............................16
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 .........................................24
3.4 GPS MODE............................................27
3.5 LO GENERATION and
DISTRIBUTION CIRCUIT ......................28
3.6 OFF-CHIP RF COMPONENTS .............29
3.7 Digital Baseband
(Stn8810 / MSM6280)............................32
3.8 Hardware Architecture ...........................34
3.9 Subsystem of STn8810..........................37
3.10 Hardware Peripheral system of
Stn8810................................................40
3.11 Subsystem of MSM6280......................46
3.12 External memory interface ...................48
3.13 Hardware sub system of MSM6280.....50
3.14 Audio and sound ..................................62
3.15 Camera interface .................................69
3.16 Bluetooth..............................................77
3.17 Main Features ......................................78
3.18 Main Component..................................79
4. TROUBLE SHOOTING ...................86
4.1 RF Component.......................................86
4.2 SIGNAL PATH .......................................88
4.3 Checking TCXO Block ...........................91
4.4 Checking Ant. Switch Module Block ......93
4.5 Checking WCDMA Block .......................95
4.6 Checking GSM Block ...........................106
4.7 Power on trouble..................................113
4.8 USB trouble..........................................115
4.9 SIM detect trouble................................116
4.10 Key sense trouble ..............................117
4.11 Keypad backlight trouble....................119
4.12 Folder on/off trouble...........................121
4.13 Micro SD trouble ................................123
4.14 Charging trouble ................................125
4.15 Audio trouble......................................127
4.16 Camera trouble ..................................140
4.17 Main LCD trouble ...............................146
4.18 Bluetooth trouble................................149
5. DOWNLOAD .................................151
5.1 COM PORT setting method when
using USB Download ...........................151
5.2 How to KT610 Download .....................154
6. BLOCK DIAGRAM ........................157
7. CIRCUIT DIAGRAM ......................165
8. BGA IC PIN CHECK......................177
9. PCB LAYOUT................................187
10. CALIBRATION & RF AUTO TEST
(HOT KIMCHI) .............................195
10.1 Usage of Hot-Kimchi ..........................195
11. TEST MODE ................................198
12. EXPLODED VIEW &
REPLACEMENT PART LIST ......201
12.1 EXPLODED VIEW .............................201
12.2 Replacement Parts
<Mechanic component>.....................207
<Main component> ............................211
12.3 Accessory ..........................................233
Table Of Contents
LGE Internal Use Only Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes

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LGE Internal Use Only Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes

LGE Internal Use Only Copyright © 2008 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

LGE Internal Use Only Copyright © 2008 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 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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LGE Internal Use Only Copyright © 2008 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 Communicator Handset
Size 108.9 X 53.9 X 17.2 mm
Weight 124 g (with 950mAh Battery)
Power 3.7V normal, 950 mAh Li-Polymer
Talk Time Over 170 min (TX = 12dBm,Low Power mode)
(with 950mAh) Over 180 min (TX Level = Max)
Standby Time Over 220 hours (DRX = 1.28)
(with 950mAh) Over 290 hours (Paging Period = 5)
Antenna Internal type and Antenna
LCD TFT LCD ( Main : 2.4’, 320 x 240, Sub :1.45” 160X64 )
LCD Backlight LED Back Light (Main, Sub)
Camera Dual Camera ; 2 Mega pixel (CMOS), VGA Camera (CMOS)
Vibrator Yes (Cylinder Type)
LED Indicator No
MIC Yes
Receiver Yes
Earphone Jack Yes
Connectivity Bluetooth, USB
Volume Key Push Type (+, -)
External Memory Micro-SD
I/O Connect 18 Pin

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Only for training and service purposes
2.2 Usable environment
2.2.1 Environment
2.2.2 Environment (Accessory)
* CLA : 12~24V(DC).
2. PERFORMANCE
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Item Specification
Voltage 3.7 V(Typ), [Shut Down : 3.22 V]
Operation Temp -20 ~ +60 °C
Storage Temp -20 ~ +70 °C
Humidity 85 % (Max)
Reference Spec. Min Typ. Max Unit
TA Power Available power 100 220 240 Vac

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Only for training and service purposes
2. PERFORMANCE
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2.3 Radio Performance
2.3.1 Transmitter - GSM Mode
* In case of DCS : [A] -> 1710, [B] -> 1785* In case of PCS : [A] -> 1850, [B] -> 1910
No Item GSM DCS & PCS
1Conducted MS allocated 100k~1GHz -39dBm 9k ~ 1GHz -39dBm
Spurious Channel 1G~[A]MHz -33dBm
Emission 1G~12.75GHz -33dBm [A]M~[B]MHz -39dBm
[B]M~12.75GHz -33dBm
Idle Mode 100k~880MHz -60dBm 100k~880MHz -60dBm
880M~915MHz -62dBm 880M~915MHz -62dBm
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
2Radiated MS allocated 30M ~ 1GHz -36dBm 30M~1GHz 36dBm
Spurious Channel 1G~[A]MHz -30dBm
Emission 1G ~ 4GHz -30dBm [A]M~[B]MHz -36dBm
[B]M~4GHz -30dBm
Idle Mode 30M ~ 880MHz -57dBm 30M~880MHz -57dBm
880M ~ 915MHz -59dBm 880M~915MHz -59dBm
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

* In case of DCS : [A] -> 1710, [B] -> 1785* In case of PCS : [A] -> 1850, [B] -> 1910
LGE Internal Use Only Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
2. PERFORMANCE
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No Item GSM DCS & PCS
3Frequency Error ± 0.1ppm ± 0.1ppm
4Phase Error ± 5(RMS) ± 5(RMS)
±20(PEAK) ± 20(PEAK)
5Frequency Error 3dB below reference sensitivity 3dB below reference sensitivity
Under Multipath and RA250 : ± 200Hz RA250: ± 250Hz
Interference Condition HT100 : ± 100Hz HT100: ± 250Hz
TU50 : ± 100Hz TU50: ± 150Hz
TU3 : ± 150Hz TU1.5: ± 200Hz
6Output RF Due to 0 ~ 100kHz +0.5dB 0 ~ 100kHz +0.5dB
Spectrum modulation 200kHz -30dB 200kHz -30dB
250kHz -33dB 250kHz -33dB
400kHz -60dB 400kHz -60dB
600 ~ 1800kHz -60dB 600 ~ 1800kHz -60dB
1800 ~ 3000kHz -63dB 1800 ~ 6000kHz -65dB
3000 ~ 6000kHz -65dB ≥ 6000kHz -73dB
≥6000kHz -71dB
Due to 400kHz -19dB 400kHz -22dB
Switching 600kHz -21dB 600kHz -24dB
transient 1200kHz -21dB 1200kHz -24dB
1800kHz -24dB 1800kHz -27dB
7Intermodulation attenuation - Frequency offset 800kHz
Intermodulation product should
be Less than 55dB below the
level of Wanted signal

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2. PERFORMANCE
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No Item GSM DCS & PCS
8Transmitter Output Power Level Power Toler. Level Power Toler.
533 ±3030 ±3
631 ±3128 ±3
729 ±3226 ±3
827 ±3324 ±3
925 ±3422 ±3
10 23 ±3 5 20 ±3
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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2.3.2 Transmitter - WCDMA Mode
No Item Specification
1Maximum Output Power Class3: +24dBm(+1/-3dB)
Class 4 : +21dBm( ± 2dB)
2Frequency Error ± 0.1ppm
3Open Loop Power control in uplink ± 9dB@normal, ± 12dB@extreme
4Inner Loop Power control in uplink Adjust output(TPC command)
cmd 1dB 2dB 3dB
+1 +0.5/1.5 +1/3 +1.5/4.5
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
5Out-band Blocking -50dBm(3.84MHz)
6Out-of-synchronization handling of output power Qin/Qout : PCCH quality levels
Toff@DPCCH/Ior : -22 -> -28dB
Ton@DPCCH/Ior : -24 -> -18dB
7Transmit OFF Power -56dBm(3.84MHz)
8Transmit ON/OFF Time Mask ± 25us
PRACH,CPCH,uplinlk compressed mode
9Change of TFC ± 25us
Power varies according to the data rate DTX :
DPCH off (minimize interference between UE)
10 Power setting in uplink compressed ± 3dB(after 14slots transmission gap)
11 Occupied Bandwidth(OBW) 5MHz(99%)
12 Spectrum emission Mask -35-15*(∆f-2.5)dBc@∆f=2.5~3.5MHz,30k
-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
13 Adjacent Channel Leakage Ratio(ACLR) 33dB@5MHz, ACP>-50dBm
43dB@10MHz, ACP>-50dBm

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2. PERFORMANCE
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No Item Specification
14 Spurious Emissions (*: additional requirement) -36dBm@f=9~150KHz, 1K BW
-36dBm@f=50KHz~30MHz, 10K BW
-36dBm@f=30MHz~1000MHz, 100K BW
-30dBm@f=1~12.5GHz, 1M BW
(*)-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
15 Transmit Intermodulation -31dBc@5MHz,Interferer -40dBc
-41dBc@10MHz, Interferer -40dBc
16 Error Vector Magnitude (EVM) 17.5%(>-20dBm)
(@12.2K, 1DPDCH+1DPCCH)
17 Transmit OFF Power -15dB@SF=4.768Kbps, Multi-code
transmission

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2. PERFORMANCE
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Only for training and service purposes
2.3.3 Receiver - GSM Mode
No Item GSM DCS & PCS
1Sensitivity (TCH/FS Class II) -105dBm -105dBm
2Co-Channel Rejection (TCH/FS C/Ic=7dB Storage -30 ~ +85
Class II, RBER, TU high/FH)
3Adjacent 200kHz C/Ia1=-12dB C/Ia1=-12dB
Channel
Rejection 400kHz C/Ia2=-44dB C/Ia2=-44dB
4Intermodulation Rejection Wanted Signal :-98dBm Wanted Signal :-96dBm
1st interferer :-44dBm 1st interferer :-44dBm
2nd interferer :-45dBm 2nd interferer :-44dBm
5Blocking Response Wanted Signal :-101dBm Wanted Signal :-101dBm
(TCH/FS Class , RBER) Unwanted : Depend on Unwanted : Depend on
Frequency Frequency

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2. PERFORMANCE
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Only for training and service purposes
2.3.4 Receiver - WCDMA Mode
No Item Specification
1Reference Sensitivity Level -106.7 dBm(3.84 MHz)
2Maximum Input Level -25dBm(3.84MHz)
-44dBm/3.84MHz(DPCH_Ec)
UE@+20dBm output power(Class3)
3Adjacent Channel Selectivity (ACS) 33dB
UE@+20dBm output power(Class3)
4In-band Blocking -56dBm/3.84MHz@10MHz
UE@+20dBm output power(Class3)
-44dBm/3.84MHz@15MHz
UE@+20dBm output power(Class3)
5Out-band Blocking -44dBm/3.84MHz@f=2050~2095 and
2185~2230MHz
UE@+20dBm output power(Class3)
-30dBm/3.84MHz@f=2025~2050 and
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)
7Intermodulation Characteristic -46dBm CW@10MHz
-46dBm/3.84MHz@20MHz
UE@+20dBm output power(Class3)
8Spurious Emissions -57dBm@f=9KHz~1GHz, 100K BW
-47dBm@f=1~12.5GHz, 1M BW
-60dBm@f=1850 MHz ≤f ≤1910 MHz,
3.84M BW
-60dBm@f=824 MHz ≤f ≤849 MHz, 3.84M BW

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2. PERFORMANCE
LGE Internal Use Only Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
2.4 Current Consumption
(Stand by and Voice Call Test Condition : LCD backlight Off)
(VT Test Condition : Speaker off, LCD backlight On,0dBm Tx power)
2.5 RSSI BAR
2.6 Battery BAR
Stand by(BT Off condition) Voice Call VT
WCDMA Under 4.32 mA Under 335 mA Under 569mA
(DRX=1.28) (Tx=10dBm) (Tx=10dBm
-Low power) -Low power)
GSM Under 4.32 mA Under 380 mA
(Paging=5period) (Tx=Max power)
Level Change CDMA GSM
7 →6-86 ± 2dBm -82 ± 2dBm
6 →5-90 ± 2dBm -86 ± 2dBm
5 →4 -94 ± 2dBm -90 ± 2dBm
4 → 3-98 ± 2dBm -94 ± 2dBm
3 →2-102 ± 2dBm -98 ± 2dBm
2 →1-106 ± 2dBm -102 ± 2dBm
1 →0-110 ± 2dBm -106 ± 2dBm
Indication Standby
Bar 7 3.96 ± 0.05V
Bar 7 → 63.95 ± 0.05V
Bar 6 → 53.86 ± 0.05V
Bar 5 → 43.78 ± 0.05V
Bar 4 → 33.74 ± 0.05V
Bar 3 → 23.69 ± 0.05V
Bar 2 → 13.63 ± 0.05V
Bar 1 → Empty 3.50 ± 0.05V
Low Voltage, 3.63,3.50 ± 0.05V (Stand-by) / 3.63, 3.50 ± 0.05V (Talk)
Warning message + tone Bar 2 → 1 / Bar 1 → Empty
Power Off 3.20 ± 0.05V

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2. PERFORMANCE
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Only for training and service purposes
2.7 Sound Pressure Level
No Test Item Specification
1Sending Loudness Rating (SLR) 8 ± 3 dB
2Receiving Loudness Rating (RLR) Nor -4 ± 3 dB
Max -15 ± 3 dB
3Side Tone Masking Rating (STMR) Min 17 dB
4Echo Loss (EL) Min 40 dB
5Sending Distortion (SD) Refer to Table 30.3
6Receiving Distortion (RD) Refer to Table 30.4
7Idle Noise-Sending (INS) Max -64 dBm0p
8Idle Noise-Receiving (INR) Nor Under -47 dBPA
Max Under -36 dBPA
9Sending Loudness Rating (SLR) 8 ± 3 dB
10 Receiving Loudness Rating (RLR) Nor -1 ± 3 dB
Max -12 ± 3 dB
11 Side Tone Masking Rating (STMR) Min 25 dB
12 Echo Loss (EL) Min 40 dB
13 Sending Distortion (SD) Refer to Table 30.3
14 Receiving Distortion (RD) Refer to Table 30.4
15 Idle Noise-Sending (INS) Max -55 dBm0p
16 Idle Noise-Receiving (INR) 16 Nor Under -45 dBPA
Max Under -40 dBPA
17 TDMA Noise Max -62 dBm
-. 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)
MS
Headset
MS and
Headset

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2. PERFORMANCE
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2.8 Charging
• Charging Method : CC & CV (Constant Current & Constant Voltage)
• Maximum Charging Voltage : 4.2 V
• Maximum Charging Current : 650mA
• Normal Battery Capacity : 950 mAh
• Charger Voltage : 4.8V
• Charging Time : Max 3 h (Except time trickle charging)
• Full charging indication current (charging icon stop current) : 60mA
• Low battery POP UP : 3.48V
• Low battery alarm interval : Idle - 3 min, Dedicated - 1min
• Cut-off voltage : 3.22V

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3. TECHNICAL BRIEF
3. TECHNICAL BRIEF
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Only for training and service purposes
3.1 GENERAL DESCRIPTION
The KT610 supports UMTS-2100, GSM-900, GSM-1800, and GSM-1900 based
GSM/GPRS/EDGE/UMTS. All receivers and the UMTS transmitter use the radioOne 1Zero-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.
A generic, high-level functional block diagram of KT610 is shown in Figure 3-1. One antenna collects
base station forward link signals and radiates handset reverse link signals. The antenna connects with
receive and transmit paths through a SKY77519(EDGE PAM+ASM). 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.
[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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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
KT610 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 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-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-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 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