LG GU280, GU285 Service Manual

Service Manual Model : GU280/GU285

Internal Use Only

Service Manual

GU280/GU285

Date: October, 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 : Solution ....................................................7

2.4 Feature .......................................................................8

2.5 HW Spec. ..................................................................10

3. Technical Brief ............................................. 13

3.1. General Description ..................................................13

3.2. WCDMA Part ............................................................14

3.3. EDGE/GPRS/GSM RF block ........................................19

3.5. Control Flow .............................................................24

3.6 General Description ...................................................25

3.7 Power management ..................................................35

4. TROUBLE SHOOTING ..................................... 38

4.1 RF Component ..........................................................38

4.2 RF Path ....................................................................39

4.3 Trouble Shooting of GSM Part (GSM850/900/1800/1900)

......................................................................................40

4.4 Trouble Shooting of WCDMA Part ................................48

4.5 Checking Bluetooth Block ..........................................55

4.6 Checking FM Radio Block ..........................................58

4.7 Base band part ..........................................................61

4.8 Charger Troubleshooting ............................................63

4.9 USB Troubleshooting ..................................................64

4.10 USIM Detect Troubleshooting ....................................66

4.11 Camera Troubleshooting ..........................................68

4.12 Main Keypad Backlight Troubleshooting ....................70

4.13 Sub Keypad Backlight Troubleshooting ......................71

4.14 LCD Troubleshooting ................................................73

4.15 Vibrator ...................................................................74

4.16 Receiver Path ..........................................................75

4.17 Headset path...........................................................77

4.18 Speaker phone path ................................................79

4.19 Main microphone ....................................................81

4.20 Headset microphone ................................................83

5. Downloading ................................................ 85

5.1 Introduction ...............................................................85

5.2 Downloading Procedure .............................................86

5.3 Troubleshooting Download Errors ..............................101

5.4 Caution ...................................................................106

6. Block Diagram ........................................... 107

7. CIRCUIT DIAGRAM ...................................... 109

8. BGA Pin Map .............................................. 117

9. PCB LAYOUT ...............................................121

10. CALIBRATION ............................................127

10.1 Conﬁ guration of directory .......................................127

10.2 How to use Tachyon ...............................................129

11. EXPLODED VIEW & REPLACEMENT

PART LIST ................................................ 131

11.1 EXPLODED VIEW ...................................................131

11.2 Replacement Parts ................................................133

11.3 Accessory ............................................................. 150

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LGE Internal Use Only

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Only for training and service purposes

1. INTRODUCTION

BL20

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

BL20

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

GU280 : WCDMA2100+EGSM/GSM850/DCS/PCS (GPRS Class 12 / EDGE Class 12)

2.2 Supporting Standard

2. PERFORMANCE

CommentFeatureItem

Supporting Standard

Frequency Range

WCDMA(FDD1)/EGSM/GSM850/DCS1800/PCS1900 with seamless handover Phase 2+(include AMR) SIM Toolkit : Class 1, 2, 3, C-E

WCDMA(FDD1) TX : 1920 – 1980 MHz WCDMA(FDD1) RX : 2110 – 2170 MHz EGSM TX : 880 – 915 MHz EGSM RX : 925 – 960 MHz GSM850 TX : 824 – 849 MHz GSM850 RX : 869 – 894 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(MIDP 2.1 CLDC 1.1)Application Standard

2.3 Main Parts : Solution

QSC6240 : QualcommDigital Baseband

QSC6240 : QualcommAnalog Baseband

QSC6240 : QualcommRF Chip

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CommentPart NameItem

QSC6240 is an one-chip solution(DB + AB + RF + PM)

LGE Internal Use Only

2. PERFORMANCE

2.4 Feature

CommentFeatureItem

Slide typeForm Factor

Battery

Size

Stand by time

Talk time

RX sensitivity

1) Capacity Standard : Li-Ion, 900mAh

2) Packing Type : Inner Pack

Standard :

96.0 x 45.7 x 14.9mm

TBDVolume

Staggered 10 Layers , 0.8tPCB

2G : Over 320 hrs 3G : Over 250 hrs

2G : Over 180mins 3G : Over 180 mins

WCDMA(FDD1) < -105 dBm EGSM < -105 dBm GSM850 < -105 dBm DCS 1800 < -105 dBm PCS 1900 <-105 dBm

With Battery115gWeight

@ Paging Period 5 (2G) @ DRX 1.28 (3G)

@ Power Off / 900mAh3 hrsCharging time

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

TX output power

WCDMA/ GSM/ GPRS

EDGE

WCDMA : 24dBm/3.84MHz,+1/-3dBm EGSM : 33dBm GSM850 : 33 dBm DCS 1800 : 30 dBm PCS 1900 : 30 dBm

GSM 900 : 27 dBm DCS 1800 : 26 dBm PCS 1900 : 26 dBm

GPRS Class 12GPRS compatibility

EDGE Class 12EDGE compatibility

- 8 -

Class3(WCDMA) Class4 (EGSM) Class4 (GSM850) Class1 (PCS) Class1 (DCS)

E2 (GSM900) E2 (PCS) E2 (DCS)

Only for training and service purposes

2. PERFORMANCE

SIM card type

Display

Keypad

Memory

Plug-In SIM 3V /1.8V

Main LCD TFT Main LCD(2’, 176 x 220)

1.3 CMOS Camera Built-in Camera

Slide Key pad : 11 Main Key pad : 15

Main : Internal Fixed TypeANT

5 PinSystem connector

3.5Phi, 4 Pole, StereoEar Phone Jack

YesPC synchronization

NAND Flash : 1Gbit SDRAM : 512Gbit

FR, EFR, HR,AMRSpeech coding

Support

(External Memory)

NoData & Fax

Built in VibratorVibrator

EDR 2.0Blue Tooth

MP3/ WMA/AAC/HE-AAC/EAAC+Music Player

MPEG4, H.263, WMV9Video Player

MPEG4, H.263, Camcorder

YesVoice Recording

YesSpeaker Phone mode

YesTravel Adapter

NoCDROM

OptionStereo Headset

OptionData Cable

NoT-Flash

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LGE Internal Use Only

2. PERFORMANCE

2.5 HW Spec.

GSM Transmitter/Receiver spec.

Item Specification

Phase Error

Frequency Error

EMC(Radiated Spurious Emission Disturbance)

Transmitter 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

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)

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

AM Suppression

-GSM : -31dBm - DCS : -29dBm

Timing Advance ± 0.5T

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

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

-98dBm/-96dBm (2.439%)

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Only for training and service purposes

WCDMA Transmitter spec.

Item Specification

2. PERFORMANCE

Transmit Frequency

Maximum Output Power

1920 MHz ~ 1980 MHz

+24 dBm / 3.84 MHz, +1 / -3 dB

Frequency Error within ±0.1 PPM

Open Loop Power Control

Minimum Transmit Power

Occupied Bandwidth

Adjacent Channel Leakage

Normal Conditions : within ±9 dB, Extreme Conditions : within ±12 dB

< -50 dBm /3.84 MHz

< 5 MHz at 3.84 Mcps (99% of power)

> 33 dB @ ±5 MHz, > 43 dB @ ±10 MHz

Power Ratio (ACLR)

Spurious Emissions

| > 12.5 MHz

|f-f

< -36 dBm / 1 kHz RW @ 9 kHz ≤ f < 150 kHz < -36 dBm / 10 kHz RW @ 150 KHz ≤ f < 30 MHz < -36 dBm / 100 kHz RW @ 30 MHz ≤ f < 1 GHz < -30 dBm / 1 MHz RW @ 1 GHz ≤ f < 12.75 GHz < -41 dBm / 300 kHz RW @ 1893.5 MHz < f < 1919.6 MHz < -67 dBm / 100 kHz RW @ 925 MHz ≤ f ≤ 935 MHz < -79 dBm / 100 kHz RW @ 935 MHz < f ≤ 960 GHz < -71 dBm / 100 kHz RW @ 1805 MHz ≤ f ≤ 1880 MHz

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

- 11 -

LGE Internal Use Only

2. PERFORMANCE

WCDMA Receiver spec.

Item Specification

Receive Frequency 2110MHz ~ 2170 MHz

Reference Sensitivity Level BER < 0.001 when Î

Maximum Input Level BER < 0.001 when Î

Adjacent Channel Selectivity (ACS)

ACS > 33 dB where BER < 0.001 when Î

= –52 dBm / 3.84 MHz @ ±5 MHz

& I

oac

Blocking Characteristic BER < 0.001 when Î

& I or I

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

blocking

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

blocking

= -106.7 dBm / 3.84 MHz

= -25 dBm / 3.84 MHz

= -103.7 dBm / 3.84 MHz

= -92.7 dBm / 3.84 MHz

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

Intermodulation BER < 0.001 when Î

& I

= -46 dBm @ F

ouw1

& I

= -46 dBm / 3.84 MHz @ F

ouw2

= -103.7 dBm / 3.84 MHz

(offset) = ±10 MHz

uw1

(offset) = ±20 MHz

uw2

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

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

blocking

= -44 dBm

Adjust output(TPC command) cmd 1dB 2dB 3dB +1 +0.5/1.5 +1/3 +1.5/4

Inner 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 group(10equal command group) +1 +8/+12 +16/+24

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Only for training and service purposes

3. Technical Brief

3.1. General Description

The RF platform of GU280 supports two different communication modes (WCDMA/GSM modes) including five communication bands (W2100/W850/GSM850/GSM900/GSM1800/GSM1900). The all the RF blocks can be divided into three main parts, which are a WCDMA part, a GSM, and

a Antenna switch module.

The simplified block diagram is shown in Figure 1.1.1

3. Technical Brief

Figure 1.1.1 Block diagram of RF part

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LGE Internal Use Only

3. Technical Brief

3.2. WCDMA Part

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.No IF filter needed . Direct IQ modulation transmitter

Figure 1.2.1. WCDMA RF structure

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Only for training and service purposes

3. Technical Brief

3.2.1. Transmitter Part

WCDMA Transmitter Block

The QSC62x0 device supports 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 lowpass filtered 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 upconverter is active at a time.

Figure 1.2.1.1 WCDMA Transceiver Architecture

The active upconverter’s output is at the desired RF channel frequency and drives the QSC output stages. These RF circuits include multiple variable-gain stages that provide transmit AGC control. A greater than 81 dB gain control range is realized using information from the on-chip Tx power detector combined

with a control signal from the baseband circuits. The wide range of driver amplifier output levels is achieved while supporting the WCDMA standard’s requirements for ACLR, spurious emissions, Rx-band noise, etc. The high-band driver amplifier output is followed by a SPDT switch that provides two high-band outputs,

thereby fulfilling the tri-band UMTS requirement. The low-band output port is driven directly by its output amplifier.

All three output ports are single-ended with 50ohm nominal impedance. Each requires a matching network to interface with its band-pass filter. Each of the three UMTS Tx output chains are functionally identical: the QSC Tx output drives the PA through the band-pass filter and a matching network; a directional coupler provides a sample of the PA output signal;

the through path of the coupler is routed to the Tx port of the duplexer; the duplexer antenna port is connected to the antenna switch; and the switch is connected to the antenna. The coupler outputs provide a low-level sample of the active transmitter’s Tx power. An on-chip power-detector circuit provides a Tx power estimate that assists in setting the transmit gains and helps ensure that the maximum allowed output power is not exceeded. The three UMTS couplers (one for each band) use a daisy-chain configuration that allows them to share the single, on-chip power detector circuit.

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LGE Internal Use Only

3. Technical Brief

3.2.2. Receiver Part

WCDMA 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 beginning with its own band-specific duplexer that separates that band’s receive and transmit paths

Figure 1.2.2.1 WCDMA Receiver schematic

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) that optimizes 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’s RF circuitry includes another gain-stepped amplifier that supplements the LNA gain steps to further extend the receiver dynamic range. The downconverter translates the active LNA’s RF signal directly to baseband, producing two analog outputs: in-phase (I) and quadrature (Q). The UMTS baseband signals are routed to lowpass filters whose passband and stopband characteristics 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

3.2.3. Power Amplifier Module

The ACPM-5201 is a fully matched 10-pin surface mount module developed for UMTS Band1. This power amplifier module operates in the 1920-1980MHz bandwidth. The ACPM-5001 meets stringent UMTS linearity requirements up to 27.5dBm output power. The 3mmx3mm form factor package is self contained, incorporating 50ohm input and output matching Networks The ACPM-5201 features 5th generation of CoolPAM circuit technology which supports 3 power modes

– bypass, mid and high power modes. The CoolPAM is stage bypass technology enhancing PAE (power added

efficiency) at low and medium power range. Active bypass feature is added to 5th generation to enhance PAE further at low output range. This helps to extend talk time. A directional coupler is integrated into the module and both coupling and isolation ports are available externally, supporting daisy chain.

The power amplifier is manufactured on an advanced InGaP HBT (hetero-junction Bipolar Transistor) MMIC (microwave monolithic integrated circuit) technology offering state-of-the-artreliability, temperature stability and ruggedness.

Figure 1.2.3.1 ACPM-5201 Functional Block Diagram

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LGE Internal Use Only

3. Technical Brief

DNIL116

C149 DNI

WCDMA_1900

WLNA_HB1_IN_M

WLNA_HB1_IN_P

4.7pL120

WCDMA_2100

WCDMA_850/900

WLNA_HB2_IN_M

WLNA_HB2_IN_P

WCDMA_LB

L119

DNI

6.8nR111

WLNA_LB_IN_M

WLNA_LB_IN_P

C160 12n

B7686FL101

ANT TX_IN

RX_OUT1

C127

RX_OUT2

DNI

GND1

GND2 GND4 GND3 GND5

1880,1960MHz

L121

DNI

C138 2.2p

B7696

FL106

3.3nC144

ANT

TX_IN

RX_OUT1

RX_OUT2

GND1

GND2 GND4

GND3 GND5

1950 MHz,2140 MHz

1.8nC116

L115 1p

C142 1.8n

B7671FL103

8.2pC148

ANT

TX_IN

RX_OUT1

RX_OUT2

GND1

GND2

GND4

GND3 GND5

836.5 MHz,881.5 MHz

L108 33p

L107

10n

L109 33p

1 8

25 79

PCS_IN_M

C126

DNI C133

2.2pC134

L118 10n

DNI C129

PCS_IN_P

C123

L117 DNI

C124

0.5p

+VPWR

C173

DNI

C135 DNI

C143

33p

DNIL123

C132 DNI

PWR_DET

C151

C158

2.2u

330p

ACPM-5201 U102

PGND

10 1

1nC128

C159 DNI

C180 DNI

411R

R109

801R

001

001 1 R

VCC1VCC2

RFINRFOUT

R103

49.9

VMODEGND

WCDMA_PA_ON0

C139

C146 680p

WCDMA_PA_ON1

VBPISO

VENCPL

10 1

+VPWR

C130

C147

2.2u

330p

1.5nC119

PA_R1

PA_R0

C140

VCC1VCC2

RFINRFOUT

VBPISO

VMODEGND

VENCPL

PGND

U104ACPM-5305

C136 DNI

C155

L125 DNI

+VPWR+VPWR

C145 680p

PA_R0

C156

C137

DNI

B9414FL104

OUT

PA_R1

G1G2G3

532

1950MHz

C141 DNI

L110 DNI

L111 DNI

2.7nC118

C150

4.7n

FL102

B9425

OUT

G1G2G3

532

836.5MHz

L122

0.5p

DNIC181

C117 33p

L124

DNI

WCDMA_1900

WCDMA_1900_TX_OUT

WCDMA_2100_TX_OUT

WCDMA_2100

DNIC125

WCDMA_900_TX_OUT

WCDMA_850/900

Figure 1.2.3.2 WCDMA PAM schematic

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Only for training and service purposes

3. Technical Brief

3.3. EDGE/GPRS/GSM RF block

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

3.3.1. Transmitter Part

GSM/EDGE Transmitter Block

The QSC62x0 device supports quad-band GSM transmissions with two separate dual-band driver amplifier 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 upconverters as well — one for low band signals and one for high band — with just one active at a time. The transmitter LO signals are generated by circuits described in next section and delivered to the upconverter circuits at the correct frequency, with the proper phase relationship, and with an adequate drive level. The SPDT switches at each driver amplifier input allow selection of the output signal: either the actual GSM signal from the upconverter or 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 amplifier 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’s burst transmissions. The ramp signal is generated by one of the baseband circuit’s Tx DACs. A switch after the baseband amplifier 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 for data transmission.

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LGE Internal Use Only

3. Technical Brief

Figure 1.3.1.1 QSC GSM transmitter signal paths functional diagram

3.3.2. Receiver Part

There are two recommended GSM receiver path configurations; both are 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 LNAs for 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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Only for training and service purposes

3. Technical Brief

Figure 1.3.2.1 QSC GSM receiver signal paths functional diagram

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LGE Internal Use Only

3. Technical Brief

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). Beginning at the antenna switch output, the GSM signal is routed through the UMTS850 duplexer to the shared LNA input at pins L22 and K22. Likewise, the GSM 1900 receive path shares the UMTS 1900 front-end, including pins J23 and H23. The GSM 900 and GSM 1800 bands 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 bandpass filters. The filter functions suppress out-of-band received signals and the handset’s GSM transmitter leakage. Transmit power suppression must be adequate to avoid overdriving the GSM Rx chain. Like the UMTS paths, the GSM paths use a differential configuration into their LNAs, and thus equire differential 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 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’s RF circuitry includes another gain-stepped amplifier that supplements the LNA gain steps to further extend the receiver dynamic range. The downconverter translates the active LNA’s RF signal directly to baseband, producing two analog outputs: in-phase (I) and quadrature (Q). The GSM baseband signals drive lowpass filters whose passband and stopband characteristics 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 downconverter circuits from the LO generation and distribution circuits as described in next section.

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 1800 and GSM 1900 bands 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 synthesizer input (REF), the frequency reference to which the PLL is phase and frequency locked. The reference 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-loop will force 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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Only for training and service purposes

3.3.4. Front-End Module (FEM)

■ Low-loss SAW frontend module for mobile telephone system

■ Covering GSM850, GSM900, GSM1800, GSM1900,

WCDMA 2100 bands

■ 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/ EGSM

■ Integration of ESD protection at Ant port to 8kV

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

3. Technical Brief

Figure 1.3.4.1 Block diagram of FEM

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LGE Internal Use Only

3. Technical Brief

3.5. Control Flow

The access side of the digital baseband controller controls the overall radio system. In both EDGE/GSM/GPRS and W-CDMA air interface mode, the digital baseband controller controls the radio system through a serial bus. The digital baseband controller also manages PA band control and the antenna switch mechanism in the front end module. The 26 MHz VCXO clock residing in the GSM/EDGE transceiver is turned on only when required, the digital baseband controller initiates this. The EDGE/GSM/GPRS RF system requires control, which is temperature dependent. The temperature within the RF system is estimated by a voltage measurement performed by the analog baseband controller. The control flow for the RF system is shown in Figure 1.5.1.

Figure 1.5.1 Block diagram of FEM

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Only for training and service purposes

3. Base Band Technical Description

3.6 General Description

QSC6240 has all eight major functional blocks as like Figure 2.1

3. Technical Brief

Figure 2.1 QSC6240 Base band block

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LGE Internal Use Only

3. Technical Brief

3.6.1 Processor

The QSC6240 device integrates multiple processors on-chip: one ARM microprocessor and two DSP processors. Each processor is part of a functional subsystem:

 The micro subsystem includes the ARM926EJ-S microprocessor.  The modem subsystem includes the QDSP4u8 digital signal processor (mDSP).  The application subsystem includes the QDSP4u8 application digital signal processor(aDSP).

Figure 2.1.1 Processors and bus architecture

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Only for training and service purposes

3. Technical Brief

3.6.2 Memory support (and LCD interface)

The QSC62x0 device has two external bus interface (EBI) ports: EBI1 and EBI2.

EBI1 supports high-speed synchronous dynamic devices. Its memory controller supports the new mobile DDR SDRAM memories with its higher bandwidth and ability to run at high clock frequencies. This interface supports the high-bandwidth, high-density, and low-latency requirements of the QSC’s advanced on-chip capabilities such as the ARM9 processor, highperformance graphics, and video applications.

EBI2 is the slower speed interface intended to support memory devices such as NAND flash and asynchronous SRAM, peripheral devices such as LCDs, and the UBM receiver for multicast or broadcast reception (QSC6270 only). In addition, EBI2 is required to support a synchronous-burst AAD NOR flash to enable a NOR/DDR SDRAM memory configuration because the simultaneous mode (NOR, SDRAM) is not supported on the EBI1 bus.

The ARM926EJ-S microprocessor is a cached processor and all its accesses to external memory use burst techniques of four or eight 32-bit words when the memory region is declared to be cacheable/bufferable. To take advantage of this QSC higher performance feature, data from memories must satisfy the requirements for these burst accesses.

DDR

SDRAM

DDR

512Mbit

SDRAM

512Mbit

External Memory (MICRO-

SD card)

EBI1 EBI2

SDRAM_CKE

SDRAM_CLK_P

SDRAM_CKE

SDRAM_CLK_N

SDRAM_CLK_P

SDRAM_CS_N

SDRAM_CLK_N

SDRAM_CS_N

SDRAM_WE_N

SDRAM_RAS_N

SDRAM_CAS_N

SDRAM_DQM[0:1]

SDRAM_DQS[0:1]

ADDRESS[0:31]

DATA[0:15]

MICROSD_CLK

MICROSD_CMD

MICROSD_DETECT

MICROSD_DATA[0:3]

QSC6240

EBI2_CS1_N

EBI2_WE_N

EB2_OE_N

EBI2_ALE

EBI2_CLE

RESOUT_N

NAND_READY

EBI2_DATA[0:15]

USIM_RST

USIM_CLK

USIM_DATA

EBI2_CS1_N

EBI2_WE_N

EB2_OE_N

EBI2_ALE

EBI2_CLE

RESOUT_N

NAND_READY

USIM

NAND E2PROM

1Gbit

USIM

NAND E2P

1Gbit

Figure 2.1.2.1 The memory control blocks of GU280

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LGE Internal Use Only

3. Technical Brief

QSC6240

LDO_LCD_2.8V

LDO_LCD_1.8V

LCD_RST

EBI2_WE_N

LCD_ADS

LCD_CS_N

EBI2_DATA[15:0]

LCD_IF(2:1)

LCD 2.0”

TFT

(176x220,QCIF)

WLED_PWR

Figure 2.1.2.2 The LCD interfaces of GU280

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Only for training and service purposes

3.6.3 Connectivity

QSC6240 has connectivity features as below

– USB-OTG; USB LS, FS, and HS (2.0 compliant) – I2C compatible for peripheral controls (1.8 V) – UART: up to 4 Mbps – Bluetooth 2.0 support via external SoC – WLAN via external device (SDIO) – NFC via external module (I2C) – FM radio via external module (I2C) – USIM, SIM, and USB-UICC support; 1.8 and 3 V – Keypad interface – SPI (master only) for peripheral support – Two secure digital controllers — WLAN and secure digital (SD) cards

3. Technical Brief

Figure 2.1.3 The connectivity of GU280

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LGE Internal Use Only

3. Technical Brief

3.6.4 GPIOs

QSC6240 has 78 configurable I/O pins

UART_BT_SEL

I2C_SDA_BL I2C_SCL_BL

113RK2.2

I2C2_SCL

I2C2_SDA

I2C_SCL I2C_SDA

VREG_MSMP_2.6V

V8.1_EMSM_GERV

8 0 3R

K2.2903R

K2.2

BT_PWR_ON

LCD_MAKER_ID

CAM_LDO_EN

103R

203R

K7.4

GSM_SW_MODE

SLIDE_DETECT

LCD_BACKLIGHT_CONT

TRK_LO_ADJ

V8.1_MAC_ODL

VGA_CAM_PWDN

VGA_CAM_RST

703RK2.2

NAND_READY

CAMIF_MCLK CAMIF_DATA[7] CAMIF_DATA[6] CAMIF_DATA[5] CAMIF_DATA[4] CAMIF_DATA[3] CAMIF_DATA[2] CAMIF_DATA[1] CAMIF_DATA[0]

CAMIF_VSYNC CAMIF_HSYNC

CAMIF_PCLK

BT_PCM_CLK

BT_PCM_DOUT

BT_PCM_DIN BT_PCM_SYNC

KEY_ROW[0] KEY_ROW[1] KEY_ROW[2] KEY_ROW[3] KEY_ROW[4]

UART1_RFR_N UART1_CTS_N

MICROSD_CLK MICROSD_DATA[3] MICROSD_DATA[2] MICROSD_DATA[1] MICROSD_DATA[0]

MICROSD_CMD

MICROSD_DETECT

PA_R0

PA_R1 ANT_SEL[0] ANT_SEL[1] ANT_SEL[2] ANT_SEL[3]

LCD_RST

USIM_DATA

USIM_CLK USIM_RST

USW_INT LCD_IF[2]

CAM_PWDN

LCD_IF[1]

CAM_RST

LCD_VSYNC

KEY_COL[0] KEY_COL[1] KEY_COL[2] KEY_COL[3] KEY_COL[4]

C309

DNI

TP302

AC3

GPIO_77

AB1

GPIO_76

AB2

GPIO_75

AA3

GPIO_74

AB8 AA7

T14 C17 C16

A16

B16

A17

B17

E15

B15

A14

F14

A13

AC5 AB6 AC4

H10

H12

B10

A10

A11

C14

B14

F13

B13

C13

F12

B12

C12

E13

B11

E12

E11

C11

E14

AA1

AA2

F11

F10

AB4

AA6

AB5

AA5

AA4

AB3

C15

V8 W9 W8 W7 W6

G6 C8

A8 W1

V2 W2 W3

GPIO_73 GPIO_72 GPIO_71 GPIO_70 GPIO_69 GPIO_68 GPIO_67 GPIO_66 GPIO_65 GPIO_64 GPIO_63 GPIO_62 GPIO_61 GPIO_60 GPIO_59 GPIO_58 GPIO_57 GPIO_56 GPIO_55 GPIO_54 GPIO_53 GPIO_52 GPIO_51 GPIO_50 GPIO_49 GPIO_48 GPIO_47 GPIO_46 GPIO_45 GPIO_44 GPIO_43 GPIO_42 GPIO_41 GPIO_40 GPIO_39 GPIO_38 GPIO_37 GPIO_36 GPIO_35 GPIO_34 GPIO_33 GPIO_32 GPIO_31 GPIO_30 GPIO_29 GPIO_28 GPIO_27 GPIO_26 GPIO_25 GPIO_24 GPIO_23 GPIO_22 GPIO_21 GPIO_20 GPIO_19 GPIO_18 GPIO_17 GPIO_16 GPIO_15 GPIO_14 GPIO_13 GPIO_12 GPIO_11 GPIO_10 GPIO_9 GPIO_8 GPIO_7 GPIO_6 GPIO_5 GPIO_4 GPIO_3 GPIO_2 GPIO_1 GPIO_0

Figure 2.1.4 GPIOs of GU280

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Only for training and service purposes

3. Technical Brief

3.6.5 Air interfaces

The supported air-interface standards and features include: (See the RF technical description)

 UMTS/WCDMA/GSM/GPRS/EDGE Specification Release ‘99 (3GPP R99)  GSM/GPRS/EDGE Specification Release 4 (3GPP R4)  UMTS/WCDMA Specification Release 5 (3GPP R5, QSC6270 only)  HSDPA and equalizer; 3.6 Mbps  Enhanced GPS position location using gpsOne (with RGR6240 IC, only QSC6270)  Integrated gpsOne functionality, featuring enhancements by SnapTrack®, Inc., to enable a

wide variety of location-based services and applications, including points of interest, personal navigation, and friend finder  Simultaneous-GPS (processes GPS using dedicated circuitry while voice and/or data signals continue to be processed separately)  1024x searcher, direct facility termination (DFT) accelerator, off-chip RAM for measured data storage

3.6.6 Internal base band functions

Several baseband circuits within the QSC6240 device provide functions that are necessary only to make the device operate properly — these functions are not generally used directly by other handset circuits and functions.

 PLLs and clock generation  Modes and resets  Security  Qfuse  JTAG/ETM

The clock block includes two PLLs, all phase-locked to the TCXO signal. These PLLs generate several different stable, low-jitter clock signals that are distributed throughout the QSC device and to external components as needed. All the required WCDMA, GSM, GPS(only QSC6270), ARM, QDSP, and most peripheral clocks are derived in some way from the TCXO (or XO) source for their operating modes, plus the 32.768 kHz oscillator for their sleep modes

Figure 2.1.6 Clock block basic architecture of QSC6240

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LGE Internal Use Only

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