LG BL20 Service Manual

Service Manual Model : BL20

Internal Use Only

Service Manual

BL20

Date: September, 2009 / Issue 1.0

Table Of Contents

1. INTRODUCTION ...............................................5

1.1 Purpose ......................................................................5

1.2 Regulatory Information .................................................5

2. PERFORMANCE ...............................................7

2.1 Product Name .............................................................7

2.2 Supporting Standard ....................................................7

2.3 Main Parts : GSM Solution ...........................................7

2.4 HW Features ..............................................................8

2.5 SW Features .............................................................10

2.6 HW SPEC. .................................................................12

3. TECHNICAL BRIEF .........................................16

3.1 GENERAL DESCRIPTION .............................................16

3.2 GSM MODE ...............................................................17

3.3 UMTS MODE .............................................................21

3.4 OFF-CHIP RF COMPONENTS ......................................26

3.5 OFF-CHIP COMPONENTS ...........................................29

3.6 General Description ...................................................33

3.7 Power management ..................................................45

3.8 SUB SYSTEM ............................................................50

4. TROUBLE SHOOTING ..................................... 57

4.1 RF Component ..........................................................57

4.2 RF Path ....................................................................59

4.3 Trouble Shooting of GSM Part (GSM900/1800/1900) ..61

4.4 Trouble Shooting of WCDMA part ................................69

4.5 Checking Bluetooth Block ..........................................75

4.6 Checking FM Radio Block ..........................................80

4.7 Power ON Troubleshooting .........................................83

4.8 Charger Troubleshooting ............................................86

4.9 USB Troubleshooting ..................................................87

4.10 USIM Detect Troubleshooting ....................................88

4.11 Camera Troubleshooting ..........................................91

4.12 Main side view LED Troubleshooting .........................93

4.13 Slide Key side view LED Troubleshooting ...................95

4.14 LCD Troubleshooting ................................................97

4.16 Receiver Path ........................................................100

4.17 Headset path.........................................................103

4.18 Speaker phone path ..............................................105

4.19 Main microphone ..................................................108

4.20 Headset microphone ..............................................110

5. Download ...................................................112

5.1 Introduction .............................................................112

5.2 Downloading Procedure ...........................................113

5.3 Troubleshooting Download Errors ..............................129

5.4 Caution ...................................................................134

6. Block Diagram ........................................... 135

7. CIRCUIT DIAGRAM ...................................... 145

8. BGA Pin Map .............................................. 159

9. PCB LAYOUT ...............................................165

10. Calibration ................................................ 175

11. Test Mode ................................................. 178

12. EXPLODED VIEW & REPLACEMENT

PART LIST ................................................ 187

12.1 EXPLODED VIEW ...................................................187

12.2 Replacement Parts ................................................189

12.3 Accessory ............................................................. 213

4.15 Vibrator Troubleshooting ...........................................99

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LGE Internal Use Only

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Only for training and service purposes

1. INTRODUCTION



1. INTRODUCTION

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.

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.

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LGE Internal Use Only

1. INTRODUCTION





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.

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Only for training and service purposes

2. PERFORMANCE

2.1 Product Name

BL20 : WCDMA900/2100+EGSM/DCS/PCS (HSDPA 3.6Mbps / GPRS Class 10 / EDGE Class 10)

2.2 Supporting Standard

Item Feature Comment Supporting Standard

Frequency Range WCDMA(FDD1) TX : 1920 – 1980 MHz

Application Standard

WCDMA(FDD1,8)/EGSM/DCS1800/PCS1900 with seamless handover Phase 2+(include AMR) SIM Toolkit : Class 1, 2, 3, C-E

WCDMA(FDD1) RX : 2110 – 2170 MHz WCDMA(FDD8) TX : 880 – 915 MHz WCDMA(FDD8) RX : 925 – 960 MHz EGSM TX : 880 – 915 MHz EGSM RX : 925 – 960 MHz DCS1800 TX : 1710 – 1785 MHz DCS1800 RX : 1805 – 1880 MHz PCS1900 TX : 1850 – 1910 MHz PCS1900 RX : 1930 – 1990 MHz WAP 2.0, JAVA 2.0

2. PERFORMANCE

2.3 Main Parts : GSM Solution

Item Part Name Comment Digital Baseband QSC6270 : Qualcomm Analog Baseband QSC6270 : Qualcomm RF Chip QSC6270 : Qualcomm

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LGE Internal Use Only

2. PERFORMANCE

2.4 HW Features

Item Feature Comment Form Factor Slider type Battery

Size Standard :

Weight 115g With Battery Volume TBD PCB LX-BUMP 2 10 Layers Stand by time 2G Up to 300 hrs

Charging time 4 hrs @ Power Off / 900mAh Talk time 2G Up to 180mins

RX sensitivity WCDMA(FDD1) : -106.7 dBm

TX output power

GPRS compatibility GPRS Class 10 EDGE compatibility EDGE Class 10 SIM card type Plug-In SIM

Display 2.4” TFT QVGA

WCDMA/ GSM/ GPRS

EDGE GSM 900 : 27 dBm

1) Capacity Standard : Li-Ion, 900mAh

2) Packing Type : Soft Pack

106.9 X 50.8 X 12.3mm

3G Up to 300 hrs

3G Up to 110 mins

WCDMA(FDD8) : -103.7 dBm EGSM : -105 dBm DCS 1800 : -105 dBm PCS 1900 : -105 dBm WCDMA : 24dBm/3.84MHz,+1/-3dBm EGSM : 33dBm DCS 1800 : 30 dBm PCS 1900 : 30 dBm

DCS 1800 : 26 dBm PCS 1900 : 26 dBm

3V /1.8V

@ Paging Period 5 (2G) @ DRX 7 (3G)

@ Power Level 5 (2G) @ Tx = 12dBm (3G)

Class3(WCDMA) Class4 (EGSM) Class1 (PCS) Class1 (DCS) E2 (GSM900) E2 (PCS) E2 (DCS)

Built-in Camera 5M CMOS Camera Status Indicator Yes Keypad Function Key : 4

Navigation Key : 5

ANT Main : Internal Fixed Type System connector 5 Pin Ear Phone Jack 3.5Phi, 4 Pole, Stereo PC synchronization Yes Memory NAND Flash : 2Gbit

SDRAM : 1Gbit Speech coding FR, EFR, HR,AMR Data & Fax Built in Data & Fax support

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Navigation Key: Cancel Key, Menu Key, Send Key, END/PWR Key

Only for training and service purposes

2. PERFORMANCE

Vibrator Built in Vibrator Blue Tooth V2.1,A2DP MIDI(for Buzzer

Function)

Music Player MP3/AAC/AAC+/WMA Video Player MPEG4, H.263 40fps@QVGA

Camcorder MPEG4, 15fps@QVGA

Voice Recording Yes Speaker Phone mode Support Travel Adapter Yes CDROM Yes Stereo Headset Yes Data Cable Yes T-Fla sh (External Memory)

SW Decoded 64Poly

Yes

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LGE Internal Use Only

2. PERFORMANCE

2.5 SW Features

Item Feature Comment RSSI 0 ~ 7 Levels Battery Charging 0 ~ 3 Levels Key Volume 0 ~ 7 Level Audio Volume 1 ~ 20 Level Time / Date Display Yes Multi-Language Yes (English,German,Dutch,Czech,

Hungarian,Croatian,Polish, Slovak,Turkish,French, Italian,Spanish,Swedish, Danish,Romanian,Greek, Portuguese,Bulgarian, TradChinese,SimpChinese, Russian,Slovenian,Korean,Icela ndic)

Quick Access Mode Dialing / Call Log / Contact / Menu /

Message / Camera / Favorite

PC Sync Schedule / Phonebook / MEMO /

SMS / Download (Photo, file) Speed Dial Yes (1~9) Voice mail center -> 1 key Profile Yes CLIP / CLIR Yes Phone Book Name + 5 Numbers + 1 Memo + 2 e-

mail + 3 Group Select + Picture +

Ringtone + Anniversary day Last Dial Number Yes Total Call DB Max 100

Last Received Number Last Missed Number Yes Total Call DB Max 100

Search by Number / Name Group 30 Fixed Dial Number Yes Service Dial Number Yes Own Number Yes Voice Memo Yes Call Reminder Yes Network Selection Automatic

Mute Yes Call Divert Yes Call Barring Yes Call Charge (AoC) Yes Call Duration Yes SMS (EMS) 1000 EMS : Release4

Yes Total Call DB Max 100

Name and Number

Total 1000 Member

LDN (SIM) N/A

(Except Text align)

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Only for training and service purposes

2. PERFORMANCE

SMS Over GPRS Yes EMS Melody / Picture Send / Receive / Save MMS MPEG4 Send / Receive / Save Long Message MAX 1000 Characters SMS 7pages

Cell Broadcast Yes Download Over the WAP Game Yes Calendar Yes Memo 100 World Clock Yes Unit Convert Currency/Surface/Length/Volume/W

Stop Watch Yes Wall Paper Yes WAP Browser Over WAP 2.0 Obigo Download Melody / Wallpaper SIM Lock Yes Operator Dependent SIM Toolkit Yes R99 MMS Yes Obigo +LG MMS Client EONS No CPHS Yes V4.2 ENS No Camera Yes 5M AF /

JAVA Yes CLDC V1.1 / MIDP V2.1

Voice Dial No IrDa No Bluetooth Yes BT 2.1+EDR

FM radio Yes

Ye s Receive only Ye s Ye s

eight/Temperature/Velocity

Yes Over WAP

Digital Zoom : x2

Download Over WAP

HFP/HSP/A2DP&AVRCP /OPP/BPP/PBAP/SPP/DUN/FTP

GPRS Yes Class 12 EDGE Yes Class 12 Hold / Retrieve Yes Conference Call Yes Max. 6 DTMF Yes Memo pad Yes TTY No AMR Yes

SyncML Yes IM Yes(Only Orange) ORANGE MSN

Email Yes

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LGE Internal Use Only

2. PERFORMANCE

2.6 HW SPEC.

1) GSM transceiver specification Item Specification

Phase Error

Frequency Error

EMC(Radiated Spurious Emission Disturbance)

ransmitter Output power and Burst

Timing Burst Timing <3.69us Spectrum due to modulation out to

less than 1800kHz offset

Spectrum due to modulation out to larger than 1800kHz offset to the edge of the transmit band

Spectrum due to switching transient

Reference Sensitivity – TCH/FS Class II(RBER) : -105dBm(2.439%) Usable receiver input level range 0.012(-15 - -40dBm) Intermodulation rejection – Speech

channels

Rms : 5° Peak : 20 °

GSM : 0.1 ppm DCS/PCS : 0.1 ppm

GSM/DCS : < -28dBm

GSM : 5dBm – 33dBm ± 3dB DCS/PCS : 0dBm – 30dBm ± 3dB

200kHz : -36dBm 600kHz : -51dBm/-56dBm

GSM : 1800-3000kHz :< -63dBc(-46dBm) 3000kHz-6000kHz : <-65dBc(-46dBm) 6000kHz < : < -71dBc(-46dBm) DCS : 1800-3000kHz :< -65dBc(-51dBm) 6000kHz < : < -73dBc(-51dBm)

400kHz : -19dBm/-22dBm(5/0), -23dBm 600kHz : -21dBm/-24dBm(5/0), -26dBm

± 800kHz, ± 1600kHz : -98dBm/-96dBm (2.439%)

AM Suppression

 GSM : -31dBm

- DCS : -29dBm

Timing Advance ± 0.5T

-98dBm/-96dBm (2.439%)

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Only for training and service purposes

2) WCDMA transmitter specification Item Specification

Transmit Frequency Band1 : 1920 MHz ~ 1980 MHz

Band8 : 880MHz~915MHz

Maximum Output Power +24 dBm / 3.84 MHz, +1 / -3 dB

Frequency Error within ±0.1 PPM Open Loop Power Control Normal Conditions : within ±9 dB,

Extreme Conditions : within ±12 dB

Minimum Transmit Power < -50 dBm /3.84 MHz

Occupied Bandwidth < 5 MHz at 3.84 Mcps (99% of power) Adjacent Channel Leakage

Power Ratio (ACLR) Spurious Emissions

|f-fc| > 12.5 MHz

> 33 dB @ ±5 MHz, > 43 dB @ ±10 MHz

< -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 < -60 dBm / 3.84 MHz RW @ 869 MHz ≤ f ≤ 894 MHz < -60 dBm / 3.84 MHz RW @ 1930 MHz ≤ f ≤ 1900 MHz < -60 dBm / 3.84 MHz RW @ 2110 MHz ≤ f ≤ 2155 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 < -41 dBm / 300 kHz RW @ 1884.5 MHz < f < 1919.6 MHz

Transmit Intermodulation < -31 dBc @ 5 MHz & < -41 dBc @ 10 MHz

when Interference CW Signal Level = -40 dBc Error Vector Magnitude < 17.5 %, when Pout ≥ -20 dBm Peak Code Domain Error

< -15 dB at Pout t -20 dBm

2. PERFORMANCE

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LGE Internal Use Only

2. PERFORMANCE

3) WCDMA receiver specification Item Specification

Receive Frequency Band1 : 2110 ~ 2170 MHz

Band8 : 925~960MHz

Reference Sensitivity Level Band1 : BER < 0.001 when Îor = -106.7 dBm / 3.84 MHz

Band8 : BER < 0.001 when Îor = -103.7 dBm / 3.84 MHz Maximum Input Level BER < 0.001 when Îor = -25 dBm / 3.84 MHz Adjacent Channel Selectivity

(ACS)

Blocking Characteristic BER < 0.001 when Îor = -103.7 dBm / 3.84 MHz

Spurious Response BER < 0.001 when Îor = -103.7 dBm / 3.84 MHz

Intermodulation BER < 0.001 when Îor= -103.7 dBm / 3.84 MHz

Spurious Emissions < -57 dBm / 100 kHz BW @ 9 kHz ≤ f < 1 GHz

ACS > 33 dB where BER < 0.001 when

Îor = -92.7 dBm / 3.84 MHz

& Ioac = –52 dBm / 3.84 MHz @ ±5 MHz

& Iblocking = -56 dBm / 3.84 MHz @ Fuw(offset) = ±10 MHz

or Iblocking = -44 dBm / 3.84 MHz @ Fuw(offset) = ±15 MHz

& Iblocking = -44 dBm

& Iouw1 = -46 dBm @ Fuw1(offset) = ±10 MHz

& Iouw2 = -46 dBm / 3.84 MHz @ Fuw2(offset) = ±20 MHz

< -47 dBm / 1 MHz BW @ 1 GHz ≤ f ≤ 12.75 GHz

Inner Loop Power Control In Uplink

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

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Only for training and service purposes

4) HSDPA transmitter specification Item Specification

Transmit Frequency Band1 : 1920 MHz ~ 1980 MHz

Band8 : 880MHz~915 MHz

Maximum 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

in table

C.10.1.4

HS-DPCCH

Power

Power step slot

step

1 Start of

2 Start of CQI 1 +/- 0.6 3 Middle of CQI 0 +/- 0.6

boundary

Ack/Nack

2. PERFORMANCE

Power

step size,

P [dB]

6 +/- 2.3

Transmitter power

step tolerance [dB]

Sub-Test : 1=1/15, 2=12/15, 3=13/15, 4=15/8, 5=15/7, 6=15/0

Frequency offset

Spectrum Emission Mask

Adjacent Channel Leakage Power Ratio (ACLR)

Error Vector Magnitude < 17.5 %, when Pout ≥ -20 dBm

5) HSDPA receiver specification

Item Specification

Receive Frequency

Maximum Input Level (BLER or R), 16QAM Only

from carrier f

2.5 ~ 3.5 MHz

3.5 ~ 7.5 MHz

7.5 ~ 8.5 MHz

8.5 ~ 12.5 MHz -49dBc 1 MHz

Sub-Test : 1=1/15, 2=12/15, 3=13/15, 4=15/8, 5=15/7, 6=15/0

> 33 dB @ ±5 MHz > 43 dB @ ±10 MHz

Band1 : 2110 ~ 2170 MHz Band8 : 925 ~ 960Hz

Sub-Test : 1=1/15, 2=12/15, 3=13/15, 4=15/8, 5=15/7, 6=15/0

BLER < 10% or R >= 700kbps

Minimum requirement

-35-15×(f-2.5)dBc

-35-1×(f-3.5)dBc

-35-10×(f-7.5)dBc

Measurement

Bandwidth

30 kHz

1 MHz 1 MHz

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LGE Internal Use Only

3. Technical Brief

3. TECHNICAL BRIEF

3.1 GENERAL DESCRIPTION

The RF platform of BL20 supports two different communication modes (WCDMA/GSM modes) including five

communication bands (W2100/W850/GSM900/GSM1800/GSM190). The all the RF blocks can be divided into

three main parts, which are a WCDMA part, a GSM, and an antenna switch Mode.

The simplifed block diagram is shown in Figure 1.1.1i

[Figure 1-1] Block diagram of RF part

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Only for training and service purposes

3. Technical Brief

3.2 GSM MODE

The EDGE/GPRS/GSM transceiver use a digital interface that is shared between receive and transmit data.

The receive interface is based on I and Q data and the transmitter interface is based on envelop and

frequency data.

The quad band EDGE/GSM/GPRS transceiver has the following general features:

Power class

GMSK low bands: Class 4 (33 dBm)

GMSK high bands: Class 1 (30 dBm)

8PSK low bands: Class E2 (27 dBm)

8PSK high bands: Class E2 (26 dBm)

Multi slot class 12 (4+4=5)

Dual Transfer Mode (DTM) class 9 (3+2=5)

Zero-IF receiver

-Polar modulation transmitter

3.2.1 GSM RECEIVER

There are two recommended GSM receiver path configurations; bothare shown in Figure 1.3.2.1. The

configuration shown on top allows the GSM 850 and GSM 1900 bands to share the UMTS 850 and UMTS 1900

paths for US applications and uses four LNA inputs to support quad-band GSM operation.

The lower example uses two LNAsfor quad-band GSM operation (one low band and one high

band), with two-way SAW filters between the antenna switch and the QSC inputs for each

band type.

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LGE Internal Use Only

3. Technical Brief

[Figure 1-2] QSC GSM receiver signal paths functional diagram

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Only for training and service purposes

3. Technical Brief

3.2.2 GSM TRANSMITTER

The QSC62x0 device supports quad-band GSM transmissions with two separate dual-band

driver amplifer outputs; in fact, most Tx active circuits are contained within the device.

Both GSM transmit paths (Figure 1.3.1.1) begin with a single, shared analog baseband

signal from the device’s baseband circuits - the same interface and baseband circuits used

by the UMTS transmitters. The GSM transmitters use the same quadrature upconvertersas well

- one for low band signals and one for high band —with just one active at a time. The

transmiter LO signals are generated by circuits described.

in next section and delivered to the upconvertercircuits at the correct frequency, with

the proper phase relationship, and with an adequate drive level.

The SPDT switches at each driver amplifier input allow selectionof the output signal:

either the actual GSM signal from the upconverteror a test signal generated by the Tx LO

synthesizer. The Tx output chain is functionally identical for both the low band and the

high band: the power amplifer is driven by the QSC device through a matching network

and a resistive attenuator; the PA output is routed to the antenna switch module whose

output is connected to the antenna. In addition to the through signal path, the QSC device

also provides the PA ramp control signal that ensures smooth transitions while the

transmitter is turned on and off for GSM’sburst transmissions.

The ramp signal is generated by one of the baseband circuit’s Tx DACs. A switch after

the baseband amplifer selects whether the DAC output signal is routed to GSM PA

module for ramping the PA up or down, or to the transmitter signal path fo

transmission.

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LGE Internal Use Only

3. Technical Brief

[Figure 1.2.2] QSC GSM transmitter signal paths functional diagram

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Only for training and service purposes

3. Technical Brief

3.3 UMTS MODE

The W-CDMA transceiver uses differential analog in-phase and quadrature-phase interfaces,

That is an IQ-interface, both in the receiver and transmitter information path..

The transceiver has the following general features:

. Power class : Power class 3 (+24dBm) in Band II and V

. Zero-IF Receiver.NoIF filter needed

. Direct IQ modulation transmitter

[Figure 1.3.1] WCDMA RF structure

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LGE Internal Use Only

3. Technical Brief

3.3.1 UMTS RECEIVER

The antenna collects the base station forward-link signal and radiates the phone’s reverse-link signal. In the

example of a multiband, multimode phone (Figure 1.2.2.1), a switch routes the antenna signals to one of the

three UMTS Rx/Tx paths, each begining with its own band-specific duplexer that separates that band’s receive

and transmit paths

[Figure 1.3.2] WCDMA Receiver schematic

Each UMTS duplexer provides a differential output signal that is comlatible with its QSC LNA input. The

duplexer-to-LNA interface requires a differential matching network (MN) thatoptimizes the power transfer

into the LNA. Although there are three UMTS LNAs, only one is active at a time. The active gain-stepped LNA

output drives a shared quadrature

Downconverter directly —an off-chip inter-stage filter is not required. The elimination of this filter is achieved

by a combination of factors:

-New on-chip QSC processing

-Higher performance achieved by the differential duplexer-to-LNA interface

-Greater duplexer suppression of Tx leakage

The downconverter’sRF circuitry includes another gain-stepped amplifier that supplements the LNA gain

steps to further extend the receiver dynamic range. The downconvertertranslates the active LNA’sRF signal

directly to baseband, producing two analog outputs: in-phase (I) and quadrature (Q). The UMTS baseband

signals are routed to lowpassfilters whose passbandand stopbandcharacteristics are optimized for the active

WCDMA waveform. Both filter outputs are buffered to drive their analog-to-digital converters for digitization.

The digital baseband outputs are routed to QSC baseband circuits for further processing.

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Only for training and service purposes

3. Technical Brief

3.3.2 UMTS TRANSMITTER

The QSC62x0 device support tri-band UMTS transmissions with three separate driver amplifier outputs; in

fact, most Tx active circuits are contained within the device. All three UMTS transmit paths (Figure 1.2.1.1)

begin with a single,shared analog baseband signal from the device’s baseband circuits. The baseband signal

is composed of two differential lines, one in-phase component and one quadrature-phase component. Each

component is lowpassfiltered and amplified to levels sufficient for driving the quadrature upconverters.

There are two upconverters—one for low-band signals and one for high band —but only one upconverteris

active at a time.

[Figure 1.3.3] WCDMA Transceiver Architecture

Each UMTS duplexer provides a differential output signal that is compatible with its QSC LNA input. The

duplexer-to-LNA interface requires a differential matching network (MN) thatoptimizes the power transfer

into the LNA. Although there are three UMTS LNAs, only one is active at a time. The active gain-stepped LNA

output drives a shared quadrature downconverterdirectly - an off-chip inter-stage filter is not required. The

elimination of this filter is achieved by a combination of factors:

-New on-chip QSC processing

-Higher performance achieved by the differential duplexer-to-LNA interface

-Greater duplexer suppression of Tx leakage. The downconverter’sRF circuitry includes another gain-stepped

amplifier that supplements the LNA gain steps to further extend the receiver dynamic range.

The downconvertertranslates the active LNA’sRF signal directly to baseband, producing two analog outputs:

in-phase (I) and quadrature (Q).

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LGE Internal Use Only

3. Technical Brief

The UMTS baseband signals are routed to lowpassfilters whose passbandand stopbandcharacteristics are

optimized for the active WCDMA waveform. Both filter outputs are buffered to drive their analog-to-digital

converters for digitization. The digital baseband outputs are routed to QSC baseband circuits for further

processing.

z Shared UMTS/GSM configuration (four GSM LNAs)

In this configuration, the GSM 850 receive path shares the UMTS 850 receiver front-end path (including

LNA).Begining at the antenna switch output, the GSM signal is routedthrough the UMTS850 duplexer to the

shared LNA input at pins L22 and K2. Likewise, the GSM 1900 receive path shares the UMTS 190front-end,

including pins J23 and H23. The GSM 900 and GSM 180bands have dedicated receive paths from the antenna

switch outputs to the QSC LNA inputs.Each band has its own band-select filter that drives its LNA input. All

four GSM bands include input filtering: the 850 and 1900 bands share the UMTS duplexer filtering, while the

900 and 1800 bands have dedicated bandpassfilters. The filter functions suppress out-of-band received

signals and the handset’s GSM transmitter leakage. Transmit power suppression must be adequate to avoid

overdrivingthe GSM Rx chain. Like the UMTS paths,

the GSM paths use a differential configuration into their LNAs, and thus equiredifferential matching networks.

The internal GSM receivers are functionally identical to the UMTS receivers: although there are multiple GSM

LNAs, only one is active at a time. The active gain-stepped LNA output drives a shared quadrature

downconverterdirectly

—an off-chip inter-stage filter is not required. The elimination of this filter is achieved by a combination of

factors:

New on-chip QSC processing

Higher performance achieved by the differential duplexer-to-LNA interface

Greater duplexer suppression of Tx leakage

The downconverter’s RF circuitry includes another gain-stepped amplifier that supplements the LNA gain

step to further extend the receiver dynamic range. The downconvertertranslates the active LNA’sRF signal

directly to baseband, producing two analog outputs: in-phase (I) and quadrature (Q). The GSM baseband

signals drive lowpass filters whose passbandand stopbandcharacteristics are optimized for the active GSM

waveform. Both filter outputs are buffered to drive their analog-to-digital converters for digitization. The

digital baseband outputs are routed to QSC baseband circuits for further processing.The Rx LO signal is

delivered to the downconvertercircuits from the LO generation and distribution circuits as described in next

section.

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Only for training and service purposes

3. Technical Brief

z Dedicated GSM configuration (two GSM LNAs)

In this configuration, the GSM 850 and GSM 1900 bands do not pass through the UMTS duplexers.

Instead, the two GSM LNA inputs are shared: the GSM 850 and GSM 900 bands share the low-band GSM LNA,

and the GSM 180and GSM 190bands share the high-band LNA. Four switch module outputs are required,

each driving its own GSM Rx path. A two-way SAW filter takes the two low-band (or high-band) single-ended

inputs from the antenna switch and provides one filtered, differential output that drives the appropriate QSC

LNA input.

Beyond the LNA inputs, this GSM receiver configuration is identical to the paths described earlier for the

shared UMTS/GSM configuration.

3.3.3. Rx LO circuits

The QSC62x0 device integrates all of the frequency synthesizer functions that generate the UMTS and GSM

receive LO signals (UHF local oscillator, PLL circuits, and loop filter), plus the distribution circuits that deliver

the quadrature LO signals to the two downconverters.

The buffered 19.2 MHz TCXO or XO signal provides the synthesizerinput (REF), the frequency refrence to

which the PLL is phase and frequency locked. The refernce is divided to create a fixed frequency input to the

phase detector, FR. The other phase detector input (FV) varies as the loop acquires a lock and is generated by

dividing the local oscillator output frequency using the feedback path’s counter. The closed-lop wilforce FV to

equal FR when locked.

If the loop is not locked, the error between FV and FR will create an error signal. This error signal is filtered by

the loop filter and applied to the local oscillator, tuning the output frequency so that the error is decreased.

Ultimately the loop forces the error to approach zero and the PLL is phase and frequency locked.

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LGE Internal Use Only

3. Technical Brief

3.4 OFF-CHIP RF COMPONENTS

3.4.1 LMSP43QL-873 (FL100: FEM)

■Low-loss SAW frontend module for mobile telephone systems e

■Covering GSM850, GSM900, GSM1800, GSM1900, WCDMA 2100bands

■Integration of TX low pass filters, switches and decoder

■Integration of GSM 850, EGSM, PCN and PCS RX SAWs

■Balanced outputs of all RX ports, diplexed for GSM 850/ EGSMa

■Integration of ESD protection at Ant port to 8kV

acc. IEC-61000-4-2 (contact discharge)

[Figure 1.4.1] Block diagram of FEM

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Only for training and service purposes

3. Technical Brief

3.4.2 W-CDMA Power Amplifier (U102/104: ACPM7383/7311) and Coupler(U101/103: LDC151G8620Q-359/LDC15874M19Q-360)

The UMTS PA output power is monitored by external power detector circuits(Coupler : and HDET function in

QSC6270). This detector voltage can be used for transmitter calibration and monitor to meet RF system

specification.

6dB Atten

F, when W1900 enabled

L127= 1nH, when W1900 enabled

PWR_DET

PA_R1 PA_R0

WCDMA_PA_ON0

PA_R0

PA_R1

WCDMA_PA_ON1

C130= 100pF, when W850 enabled L110= DNI, when W850 enabled

[Figure 1.4.2] W-CDMA PAM, HDET, and Duplexer circuits.

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LGE Internal Use Only

3. Technical Brief

3.4.3 GSM850/EGSM/DCS/PCS Dual band Transmit Power Amplifier

(U101: TQM7M5012)

The dual band PA is operating to transmit for low band (GSM-850, GSM-900) and high band (GSM-1800,

GSM1900). Operating mode is selected and controlled by the QSC6270.(GSM_PA_BAND)

TX_GSM_HB

GSM_PA_BAND

DNI

GSM_PA_EN

GSM_PA_RAMP

GSM TX

3dB

B9442

3dB

EGSM Tx

SFSY0037601

B9442

TX_GSM_LB

[Figure 1.4.3] GSM900 /DCS/PCS TX Power Amplifier path

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Only for training and service purposes





3.5 OFF-CHIP COMPONENTS

3.5.1 Bluetooth (BCM2070)

3. Technical Brief

Bluetooth block of BL20 consists of a BCM2070 chip-set, an external crystal oscillator(26MHz), and a

Bluetooth chip antenna (2.4GHz). QSC6270, which is main HW solution of BL20 Model, doesn’t include BT

baseband core. Instead, Bluetooth chipset, BCM2070, contains stand-alone baseband processor (V2.1+EDR)

as well as BT RF block. An external crystal oscillator (26MHz) is used to provide reference frequency to

BCM2070.

Figure 1 shows the Bluetooth system architecture in the BL20.

[Figure 1.5] Bluetooth system architecture

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LGE Internal Use Only

3. Technical Brief





Table 1. Bluetooth Connection(GPIO) with QSC6270

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Only for training and service purposes





3.5.2 FM Receiver (TEA5991)

3. Technical Brief

The TEA5991 is a single chip FM stereo radio with RDS and RBDS decoder. The radio can be connected to a

headphone antenna and can tune from 70-108 MHz to cover the European, US, Chinese and Japanese FM

band. The radio delivers stereo audio output to an external amplifier. The radio can be controlled with a high

level command based interface through a I2C or SPI-bus.

[Figure3.xx.x.x] shows the FM Radio system architecture in the BL20.

5pin MicroUSB Connector

FM_ANT

TEA5991

FM_R FM_L

FM_I2C_SDA FM_I2C_SDL

QSC6270

[Figure3.xx.x.x]

HP_R

HP_L

HP_EAR_R

HP_EAR_L

AUDIO

SUBSYSTEM

Pin Descriptions

[Figure3.xx.x.x]

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LGE Internal Use Only

+ 183 hidden pages

LG BL20 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual