LG KV600 Service Manual

CDMA Mobile Subscriber Unit

LG-KV600

SERVICE MANUAL

CDMA MOBILE PHONE

SINGLE BAND

Only for training and service purpose.

-1-

Table of Contents

General Introduction.....................3

CHAPTER 1. System Introduction...........4

1.1 System Introduction................4

1.2 Features and Advantages of CDMA

Mobile Phone (For AMPS as well)....5

1.3 Structure and Functions of dual-band

CDMA Mobile Phone..................8

1.4 Specification......................9

1.5 Installation......................13

CHPATER 2. NAM Input Method.............14

2.1 NAM Program Method and Telephone

Number Inputting Method...........14

CHAPTER 3. Circuit Description..........15

3.1 RF Transmit/Receive Part..........15

3.2 Digital/Voice Processing Part.....20

CHAPTER 4. Trouble Shooting.............24

4.1 Rx Part Trouble...................24

4.1.1 When Rx power isn’t enough...24

4.1.2 Checking TCXO Circuit.........25

4.1.3 Checking Mobile S/W & Duplexer26

4.1.4 Checking LNA & SAW(DCN).......28

4.1.5 Check PAM Circuit.............29

4.1.6 BLUETOOTH Trouble.............31

4.1.7 GPS Trouble...................33

4.2 Logic Part Troubleshooting.......35

4.2.1 Power on trouble..............35

4.2.2 Battery Charging Trouble......39

4.2.3 Camera Trouble................42

4.2.4 LCD Trouble...................50

4.2.5 Speaker Trouble...............54

4.2.6 MIC Trouble...................61

4.2.7 Headset trouble...............63

4.2.8 Keypad Backlight Trouble......67

4.2.9 Motor Trouble.................70

4.2.10 7-SEG LED trouble............73

CHAPTER 7. Appendix.......................92

7.1 KV600 Block and Circuit diagram.....93

7.2 BGA Pin Map........................101

7.3 KV600 Component Layout.............106

7.3.1 KV600 Layout Diagram...........106

7.3.1.1 KV600 MAIN Layout Diagram...106

7.3.1.2 KV600 F-KEY Layout Diagram..108

7.3.1.3 KV600 F-MAIN Layout Diagram.110

7.3.2 KV600 Circuit Diagram..........112

7.3.2.1 KV600 Main Circuit Diagram..112

7.3.2.2 KV600 F-KEY Circuit Diagram.117

7.3.2.3 KV600 F-MAIN Circuit Diagram118

7.4 KV600 Exploded view................120

7.5 KV600 Part List....................122

7.5.1 KV600 Main PCB Part List.......122

7.5.2 KV600 F-KEY PCB Part List......130

7.5.3 KV600 F-MAIN PCB Part List.....131

CHAPTER 5. Safety.......................76

CHAPTER 6. Glossary.....................79

Only for training and service purpose.

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General Introduction

The LG-KV600 phone has been designed to operate on the latest digital mobile communication technology,

Code Division Multiple Access (CDMA). This CDMA digital technology has greatly enhanced voice clarity and

can provide a variety of advanced features.

The CDMA technology adopts DSSS (Direct Sequence Spread Spectrum). This feature of DSSS enables the

phone to keep communication from being crossed and to use one frequency channel by multiple users in the

same specific area, resulting that it increases the capacity 10 times more compared with that in the analog mode

currently used. Soft/Softer Handoff, Hard Handoff, and Dynamic RF power Control technologies are combined

into this phone to reduce the call being interrupted in a middle of talking over the phone. CDMA network

consists of MSO (Mobile Switching Office), BSC (Base Station Controller), BTS (Base station Transmission

System), and MS (Mobile Station). The following table lists some major CDMA Standards.

- TIA/EIA/IS-95-A/B/C (Common Air Interface) : Protocol between MS and BTS

- TIA/EIA/IS-96-B : Speech CODEC

- TIA/EIA/IS-98 : Basic MS functions

- IS-126 : Voice loopback

- TIA/EIA/IS-99 : Short Message Service, Asynchronous Data Service, and G3 Fax Service

Only for training and service purpose.

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Chapter 1. System Introduction

1. System Introduction

1.1 CDMA Abstract

The CDMA mobile communication system has a channel hand-off function that is used for collecting the

information on the locations and movements of mobile telephones from the cell site by automatically controlling

several cell site through the setup of data transmission routes, and then enabling one switching system to carry

out the automatic remote adjustment. This is to maintain continuously the call state through the automatic

location confirmation and automatic radio channel conversion when the busy subscriber moves from the service

area of one cell site to that of another by using automatic location confirmation and automatic radio channel

conversion functions. The call state can be maintained continuously by the information exchange between

switching systems when the busy subscriber moves from one cellular system area to the other cellular system

area.

In the cellular system, the cell site is a small-sized low output type and utilizes a frequency allocation system

that considers mutual interference, in an effort to enable the re-use of corresponding frequency from a cell site

separated more than a certain distance. The analog cellular systems are classified further into an AMPS system,

E-AMPS System, NMT system, ETACS system, and JTACS system depending on technologies used.

Unlike the time division multiple access (TDMA) or frequency division multiple access (FDMA) used in the

band limited environment, the Code Division Multiple Access (CDMA) system which is one of digital cellular

systems is a multi-access technology under the interference limited environment. It can process more number of

subscribers compared to other systems (TDMA system has the processing capacity three times greater than the

existing FDMA system whereas CDMA system, about 12~15 times of that of the existing system).

CDMA system can be explained as follows; TDMA or CDMA can be used to enable each person to talk

alternately or provide a separate room for each person when two persons desire to talk with each other at the

same time, whereas FDMA can be used to enable one person to talk in soprano, whereas the other in bass (one

of the two talkers can carry out synchronization for hearing in case there is a bandpass filter function in the area

of the hearer). Another available method is to make two persons to sing in different languages at the same time,

space, and frequency when wishing to let the audience hear the singing without being confused. This is the

characteristic of CDMA.

On the other hand, when employing the CDMA technology, each signal has a different pseudo-random binary

sequence used to spread the spectrum of carrier. A great number of CDMA signals share the same frequency

spectrum. In the perspective of frequency area or time area, several CDMA signals are overlapped. Among these

types of signals, only desired signal energy is selected and received through the use of pre-determined binary

sequence; desired signals can be separated, and then received with the correlator used for recovering the

spectrum into its original state. At this time, the spectrums of other signals that have different codes are not

recovered into its original state, and appears as the self-interference of the system.

Only for training and service purpose.

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1.2. Features and Advantages of CDMA Mobile Phone

1.2.1 Various Types of Diversities

When employing the narrow band modulation (30kHz band) that is the same as the analog FM modulation

system used in the existing cellular system, the multi-paths of radio waves create a serious fading. However, in

the CDMA broadband modulation (1.25MHz band), three types of diversities (time, frequency, and space) are

used to reduce serious fading problems generated from radio channels in order to obtain high-quality calls.

Time diversity can be obtained through the use of code interleaving and error correction code whereas frequency

diversity can be obtained by spreading signal energy to wider frequency band. The fading related to normal

frequency can affect the normal 200~300kHz among signal bands and accordingly, serious effect can be avoided.

Moreover, space diversity (also called path diversity) can be realized with the following three types of methods.

First, it can be obtained by the duplication of cell site receive antenna. Second, it can be obtained through the

use of multi-signal processing device that receives a transmit signal having each different transmission delay

time and then, combines them. Third, it can be obtained through the multiple cell site connection (Soft Handoff)

that connects the mobile station with more than two cell sites at the same time.

1.2.2 Power Control

The CDMA system utilizes the forward (from a base station to mobile stations) and backward (from the mobile

station to the base station) power control in order to increase the call processing capacity and obtain high-quality

calls. In case the originating signals of mobile stations are received by the cell site in the minimum call quality

level (signal to interference) through the use of transmit power control on all the mobile stations, the system

capacity can be maximized. If the signal power of mobile station is received too strong, the performance of that

mobile station is improved. However, because of this, the interference on other mobile stations using the same

channel is increased and accordingly, the call quality of other subscribers is reduced unless the maximum

accommodation capacity is reduced.

In the CDMA system, forward power control, backward open loop power control, and closed loop power control

methods are used. The forward power control is carried out in the cell site to reduce the transmit power on

mobile stations less affected by the multi-path fading and shadow phenomenon and the interference of other cell

sites when the mobile station is not engaged in the call or is relatively nearer to the corresponding cell site. This

is also used to provide additional power to mobile stations having high call error rates, located in bad reception

areas or far away from the cell site.

The backward open loop power control is carried out in a corresponding mobile station; the mobile station

measures power received from the cell site and then, reversely increases/decreases transmit power in order to

compensate channel changes caused by the forward link path loss and terrain characteristics in relation to the

mobile station in the cell site. By doing so, all the mobile transmit signals received by the base station have same

strength.

Moreover, the backward closed loop power control used by the mobile station is performed to control power

using the commands issued out by the cell site. The cell site receives the signal of each corresponding mobile

station and compares this with the pre-set threshold value and then, issues out power increase/decrease

commands to the corresponding mobile station every 1.25msec (800 times per second). By doing so, the gain

tolerance and the different radio propagation loss on the forward/backward link are complemented.

Only for training and service purpose.

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1.2.3 Voice Encoder and Variable Data Speed

The bi-directional voice service having variable data speed provides voice communication which employs

voice encoder algorithm having power variable data rate between the base station and the mobile station. On the

other hand, the transmit voice encoder performs voice sampling and then, creates encoded voice packets to be

sent out to the receive voice encoder, whereas the receive voice encoder demodulates the received voice packets

into voice samples.

One of the two voice encoders described in the above is selected for use depending on inputted automatic

conditions and message/data; both of them utilize four-stage frames of 9600, 4800, 2400, and 1200 bits per

second for cellular. In addition, this type of variable voice encoder utilizes adaptive threshold values on

selecting required data rate. It is adjusted in accordance with the size of background noise and the data rate is

increased to high rate only when the voice of caller is inputted.

Therefore, background noise is suppressed and high-quality voice transmission is possible under the

environment experiencing serious noise. In addition, in case the caller does not talk, data transmission rate is

reduced so that the transmission is carried out in low energy. This will reduce the interference on other CDMA

signals and as a result, improve system performance (capacity increased by about two times).

1.2.4 Protecting Call Confidentiality

Voice privercy is provided in the CDMA system by means of the private long code mask used for PN spreading.

Voice privacy can ve applied on the traffic channels only. All calls are initiated using the public long code mask

for PN spreading. The mobile station user may request voice privacy during call setup using the origination

message or page response message, and during traffic channel operation using the long code transition request

order.

The Transition to private long code mask will not be performed if authentication is not performed. To initiate a

transition to the private or public long code mask, either the base station or the mobile station sends a long code

transition request order on the traffic channel.

1.2.5 Soft Handoff

A handoff in which the mobile station commences communications with a new base station without interrupting

communications with the old base station. Soft handoff can only be used between CDMA channels having

identical freqeuncy assignments.

1.2.6 Frequency Re-Use and Sector Segmentation

Unlike the existing analog cellular system, the CDMA system can reuse the same frequency at the adjacent cell.

there is no need to prepare a separate frequency plan. Total interference generated on mobile station signals

received from the cell site is the sum of interference generated from other mobile stations in the same cell site

Only for training and service purpose.

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and interference generated from the mobile station of adjacent cell site. That is, each mobile station signal

generates interference in relation to the signals of all the other mobile stations.

Total interference from all the adjacent cell sites is the ratio of interference from all the cell sites versus total

interference from other mobile stations in the same cell site (about 65%). In the case of directional cell site, one

cell normally uses a 120°sector antenna in order to divide the sector into three. In this case, each antenna is used

only for 1/3 of mobile stations in the cell site and accordingly, interference is reduced by 1/3 on the average and

the capacity that can be supported by the entire system is increased by three times.

1.2.7 Soft Capacity

The subscriber capacity of the CDMA system is flexible depending on the relation between the number of

users and service classes. For example, the system operator can increase the number of channels available for

use during the busy hour despite the drop in call quality. This type of function requires 40% of normal call

channels in the standby mode during the handoff, in an effort to avoid call disconnection resulting from the lack

of channels.

In addition, in the CDMA system, services and service charges are classified further into different classes so that

more transmit power can be allocated to high class service users for easier call set-up; they can also be given

higher priority of using hand-off function than the general users.

Only for training and service purpose.

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1.3. Structure and Functions of tri-band CDMA Mobile Phone

The hardware structure of CDMA mobile phone is made up of radio frequency (RF) part and logic part. The RF

part is composed of Receiver part (Rx), Transmitter part (Tx) and Local part (LO). For the purpose of operating

on tri-band, It is necessary dual Tx path, tri Rx path, dual PLL and switching system for band selection. The

mobile phone antenna is connected with the diplexer which divide antenna input/output cellular frequency band

(824~894 Mhz) and GPS frequency band(1575.42 MHz). The cellular path is linked with the cellular duplexer.

Duplexer carrys out seperating Rx band and Tx band. The Rx signals from the antenna are converted into

intermediate frequency(IF) band by the frequency synthesizer and frequency down converter. And then, pass

SAW filter which is a band pass filter for removing out image frequency. The IF output signals that have been

filtered is converted into digital signals via Analog-to-Digital Converter (ADC). In front of the ADC, switching

system is required to choose which band path should be open.

The digital signals send to 5 correlators in each CDMA de-modulator. Of these, one is called a searcher whereas

the remaining 4 are called data receivers (fingers). Digitalized IF signals include a great number of call signals

that have been sent out by the adjacent cells. These signals are detected with pseudo-noise sequence (PN

equence).

Signal to interference ratio (C/I) on signals that match the desired PN sequence are increased through this type

of correlation detection process, but other signals obtain processing gain by not increasing the ratio. The carrier

wave of pilot channel from the cell site most adjacently located is demodulated in order to obtain the sequence

of encoded data symbols. During the operation with one cell site, the searcher searches out multi-paths in

accordance with terrain and building reflections. On three data receivers, the most powerful 3 paths are allocated

for the parallel tracing and receiving. Fading resistance can be improved a great deal by obtaining the diversity

combined output for de-modulation. Moreover, the searcher can be used to determine the mostpowerful path

from the cell sites even during the soft handoff between the two cell sites. Moreover, 3 data receivers are

allocated in order to carry out the de-modulation of these paths. Output data that has been demodulated changes

the data string in the combined data row as in the case of original signals(deinterleaving), and then, are

demodulated by the forward error correction decoder which uses the Viterbi algorithm. Mobile station user

information send out from the mobile station to the cell site pass through the digital voice encoder via a mike.

Then, they are encoded and forward errors are corrected through the use of convolution encoder. Then, the order

of code rows is changed in accordance with a certain regulation in order to remove any errors in the interleaver.

Symbols made through the above process are spread after being loaded onto PN carrier waves. At this time, PN

sequence is selected by each address designated in each call.

Signals that have been code spread as above are digital modulated (QPSK) and then, power controlled at the

automatic gain control amplifier (AGC Amp). Then, they are converted into RF band by the frequency

synthesizer synchronizing these signals to proper output frequencies.

Transmit signals obtained pass through the duplexer filter and then, are sent out to the cell site via the antenna.

Only for training and service purpose.

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1.4. Specification

1.4.1 General Specification

1.4.1.1 Transmit/Receive Frequency Interval :

1.4.1.2 Number of Channels (Channel Bandwidth)

1.4.1.3 Operating Voltage :

DC 3.25~4.2V

1.4.1.4 Battery Power Consumption :

SLEEP IDLE MAX POWER

CELLULAR

1.5 mA 100mA 500 mA (24 dBm)

DC 3.7V

1.4.1.5 Operating Temperature :

1.4.1.6 Frequency Stability :

-20°C ~ +60°C

0.5PPM

±

CELLULAR : 45 MHz

: 20CH (BW : 1.23MHz)

1.4.1.7 Antenna :

Internal Antenna, 50 Ω

1.4.1.8 Size and Weight

1) Size : 15.5(H) x 52(W) x 102.9(D) mm

2) Weight : 112g (with 900mAh Battery)

1.4.1.9 Channel Spacing :

1.25MHz

1.4.1.10 Battery Type, Capacity and Orerating Time.

Standby Time DCN (Slot Cycle 2)

Talk Time DCN (Slot Cycle 2)

Unit = Hours, Minutes

Standard (1100mAh)

150Min.( Cell Power –92dBm Half Rate)

About 150 Hrs (SCI=2)

Only for training and service purpose.

-9-

1.4.2 Receive Specification

1.4.2.1 Frequency Range

1.4.2.2 Local Oscillating Frequency Range

1.4.2.3 Sensitivity :

1.4.2.4 Selectivity

1) CELLULAR : 3dB C/N Degration (With Fch±1.25 kHz : -30dBm)

1.4.2.5 Interference Rejection

1) Single Tone : -30dBm at 900 kHz (CELLULAR)

2) Two Tone : -43dBm at 900 kHz & 1700kHz(CELLULAR)

1.4.2.6 Spurious Wave Suppression

1.4.2.7 CDMA Input Signal Range

: 869.820 MHz ~ 893.190 MHz

: 1738.08MHz ~ 1787.94MHz

-104dBm ( C/N 12dB or more)

: Maximum of -80dB

z Dynamic area of more than -115~ -12.6 dB : 102.4dB at the 1.23MHz band

1.4.3 Transmit Specification

1.4.3.1 Frequency Range

1) CELLULAR : 824.820MHz ~ 848.190MHz

1.4.3.2 Output Power

1) CELLULAR : 0.251W

1.4.3.3 CDMA TX Frequency Deviation :

1) CELLULAR: +300Hz or less

1.4.3.4 CDMA TX Conducted Spurious Emissions

1) CELLULAR : 900kHz : - 42 dBc/30kHz below

1.98MHz : - 54 dBc/30kHz below

1.4.3.5 CDMA Minimum TX Power Control

1) CELLULAR : - 50dBm below

Only for training and service purpose.

-10-

4.4

1.

MS (Mobile Station) Transmitter Frequency

1.

4.4.1 CELLULAR mode

Ch # Center Freq. (MHz) Ch # Center Freq. (MHz)

1011

29

70

111

152

193

234

275

316

363

824.640

825.870

827.100

828.330

829.560

830.790

832.020

833.250

834.480

835.890

404

445

486

527

568

609

650

697

738

779

837.120

838.350

839.580

840.810

842.040

843.270

844.500

845.910

847.140

848.370

Only for training and service purpose.

-11-

1.4.5 MS (Mobile Station) Receiver Frequency

1.

4.5.1 CELLULAR mode

Ch. # Center Freq. (MHz) Ch. # Center Freq. (MHz)

1011

29

70

111

152

193

234

275

316

363

869.640

870.870

872.100

873.330

874.560

875.790

877.020

878.250

879.480

880.890

404

445

486

527

568

609

650

697

738

779

882.120

883.350

884.580

885.810

887.040

888.270

889.500

890.910

892.140

893.370

Only for training and service purpose.

-12-

1.5. Installation

1.5.1 Installing a Battery Pack

1) The Battery pack is keyed so it can only fit one way. Align the groove in the battery pack with the rail on the

back of the phone until the battery pack rests flush with the back of the phone.

2) Slide the battery pack forward until you hear a “click”, which locks the battery in place.

1.5.2 For Adapter Use

1) Plug the adapter into a wall outlet. The adapter can be operated from a 110V source. When AC power is

connected to the adapter.

2) Insert the adapter jack into the phone with the installed battery pack.

Red light indicates battery is being charged.. Green light indicates battry is fully charged.

Only for training and service purpose.

-13-

CHAPTER 2. NAM Input Method

(Inputting of telephone numbers included)

2.1 NAM Programming Method and Telephone Number Input Method

Press ******159753 > 1>4

z

Then, the following Menu is appeared.

1 : Phone Model 2 : SlotCycle Idx 3 : Phone Number 4 : Nam Name 5 : MCC

6

Press ******159753 > 1>3

z

1 : Phone Model 2 : SlotCycle Idx 3 : Phone Number 4 : Nam Name 5 : MCC

Press a number what you want to edit.

z

Press [edit] to edit, after input, press [OK] to save

z

To reset the handset, press [END]

z

Only for training and service purpose.

-14-

CHAPTER 3. Circuit Description

3.1. RF Transmit/Receive Part

3.1.1 Overview

The RF transmit/receive part employs the direct conversion architecture (ZIF, Zero Intermediate Frequency).

The transmit/receive frequency is respectively 824.04~848.97MHz and 869.04~893.97 MHz. The block diagram

is shown in [Figure 3-1].

RF signals received through the antenna are fed QSC6085 through the duplexer. And then, they pass the low

noise amplifier (LNA), combined with the signals of local oscillator (VCO) at the frequency mixer in order to

create baseband signal directly.

Baseband signals created are changed into digital signals by the analog / digital converter (ADC, A/D

Converter) and then, auto gain controlled and, are demodulated by the modulator / demodulator.

In the case of transmission, QSC6085 modulates, interpolates, and converts the digital signal into an analog

baseband before upconverts the Tx analog baseband into RF.

The baseband quadrature signals are upconverted to the Cellular Tx frequency bands and amplified to provide

signal drive capability to the power amp.

After that, the RF signal is amplified by the Power Amp in order to have enough power for radiation. Finally,

the RF signal is sent out to the cell site via the antenna after going through the

duplexer

Only for training and service purpose.

-15-

[Figure 1-1] Block Diagram Of KV600

3.1.2 Description of Rx Part Circuit

3.1.2.1 Duplexer(DP1000)

The Duplexer consists of the Rx bandpass filter (BPF) and the Tx BPF which has the function of separating Tx

and Rx signals in the full duplex system for using the common antenna. The Tx part BPF is used to suppress

noises and spurious out of the Tx frequency band. The Rx BPF is used to receive only Rx signal coming from

the antenna, which is usually called preselector. It’s main function is to limit the bandwidth of spectrum reaching

the LNA and mixer, attenuate receiver spurious response and suppress local oscillator energy. As a result

frequency sensitivity and selectivity of mobile phone increase. The specification of LG-KV600 duplexer is

described below ;

z Cellular Duplexer

Pass Band

Insertion Loss

Return Loss

Attenuation

48dB min (869~894MHz) 60dB min (824~849MHz) 60dB (824~849MHz)

Tx Rx Tx to Rx (min)

824~849MHz 869~894 MHz

2.0dB max 2.5dB max

12dB min 12dB min

50dB (869~894MHz)

3.1.2.2 Rx RF SAW FILTER (F102)

The main function of Rx RF SAW filter is to attenuate mobile phone spurious frequency, attenuate noise

amplified by the LNA and suppress second harmonic originating in the LNA.

3.1.2.3 Down-converter Mixers

The QSC6085 device performs signal direct-down-conversion for Cellular applications. It contains all the

circuitry (with the exception of external filters) needed to support conversion of received RF signals to baseband

signals. The LO Buffer Amplifier buffers the RF VCO to the RF Transmit Upconverter. QSC6085 offers the

most advanced and integrated CDMA Rx solution designed to meet cascaded Noise Figure (NF) and Third-order

Intercept Point (IIP3) requirements of IS-98C and J-STD-018 specifications for Sensitivity, Two-Tone

Intermodulation, and Single-tone Desense.

Operation modes and band selection are specially controlled from the Mobile Station Modem QSC6085.

Only for training and service purpose.

-16-

● Cellular

High current mode Mid current mode Low current mode

Noise Figure

High Gain mode

Low Gain mode

Input IP3

High Gain mode

Low Gain mode

Input IP2

High Gain mode

Low Gain mode

● Cellular

10dB

25dB

4.0dB

-5.0dB

56dB

30dB

10dB

25dB

4.0dB

-5.0dB

56dB

30dB

9dB

25dB

-10.0dB

-5.0dB

40dB

30dB

High current mode Mid current mode Low current mode

Noise Figure

High Gain mode

Low Gain mode

Input IP3

High Gain mode

Low Gain mode

Input IP2

High Gain mode

Low Gain mode

10dB

25dB

4.0dB

-11.0dB

56dB

30dB

10dB

25dB

-8.0dB

-11.0dB

56dB

30dB

9dB

25dB

-8.0dB

-11.0dB

40dB

30dB

Only for training and service purpose.

-17-

3.1.3 Description of Transmit Part Circuit

3.1.3.1 Description on the Internal Circuit of QSC6085(U2000)

For the transmit data path(Tx), the QSC6085 modulates, interpolates, and converts the digital signal into an

analog baseband, and upconverts the Tx analog baseband into RF. The QSC6085 communicates with the

external RF and analog baseband to control signal gain in the RF Rx and Tx signal paths, educe base band offset

errors, and tune the system frequency reference.

The QSC6085 baseband-to-RF Transmit Processor performs all Tx signal-processing functions required

between digital baseband and the Power Amplifier Module (PAM). The baseband quadrature signals are

upconverted to the Cellular frequency bands and amplified to provide signal drive capability to the PAM. The

QSC6085 includes an mixer for up-converting analog baseband to RF, a programmable PLL for generating Tx

and Rx LO frequency, cellular driver amplifier and Tx power control. As added benefit, the single sideband

upconversion eliminates the need for a band-pass filter normally required between the upconverter and driver

amplifier.

I, I/, Q and Q/ signals are modulated by Offset Quadrature Phase Shift King (OQPSK). I and Q are 90 deg. out

of phase, and I and I/ are 180 deg. The mixer in QSC6085 converts baseband signals into RF signals. After

passing through the upconverters, RF signal is inputted into the Power Amplifier Module.

The QSC6085 Cellular CDMA RF specifications are described below:

Condition Min. Typ. Max. Unit

Maximum Output Power

Noise power

ACPR

869-894 MHz, all power levels -135.0 dBm/Hz

±885kHz, < 2:1 VSWR

±1.98MHz, < 2:1 VSWR

28 dBm

-44

-57

dBc

3.1.3.2 Power Amplifier (U1003)

The power amplifier that can be used in the CDMA mode has linear amplification capability.

For higher efficiency, it is made up of one module (Monolithic Microwave Integrated Circuit) for which RF

input terminal and internal interface circuit are integrated onto one IC after going through the GaAs HBT

(heterojunction bipolar transistor) process.

The module of power amplifier is made up of an output end interface circuit including this module.

The maximum power that can be inputted through the input terminal is 8dBm and conversion gain is about

28.5dB. RF transmit signals that have been amplified through the power amplifier are sent to the duplexer.

Only for training and service purpose.

-18-

3.1.4 Description of Frequency Synthesizer Circuit

3.1.4.1 Crystal Oscillator (U1007)

Crystal Unit generates the refrence frequency of 19.2MHz. Tolerance at 25°C is ±12x10-6 Max.Tolerance over

the tmperature range is ±12x10-6 Max. at -30 to 85°C

3.1.4.2 Crystal Oscillator (U2001)

Crystal Unit generates the refrence frequency of 32.768KHz. Tolerance at 25°C is ±12x10-6 Max.Tolerance

over the tmperature range is ±12x10-6 Max. at -30 to 85°C

Only for training and service purpose.

-19-

3.2 Digital/Voice Processing Part

3.2.1 Overview

The digital/voice processing part processes the user's commands and processes all the digital and voice signal

processing in order to operate in the phone. The digital/voice processing part is made up of a keypad/LCD,

receptacle part, voice processing part, mobile station modem part, memory part, and power supply part.

3.2.2 Configuration

3.2..2.1 Keypad/LCD and Receptacle Part

This is used to transmit keypad signals to QSC6085. It is made up of a keypad backlight part that illuminates the

keypad, LCD part that displays the operation status on to the screen, and a receptacle that receives and sends out

voice and data with external sources.

3.2.2.2 Voice Processing Part

The voice processing part is made up of an audio codec in QSC6085 used to convert MIC signals into digital

voice signals and other external MIDI Synthesizer used to convert digital voice signals into analog voice signals,

amplifying parts for amplifying the voice signals and MIC signals are on external MIDI Synthesizer and Codec

in QSC6085.

3.2.2.3 QSC6085 (Mobile Station Modem) Part

QSC6085 is the core elements of a CDMA mobile station and carries out the functions of CPU, encoder,

interleaver, deinterleaver, Viterbi decoder, Mod/Demod, codec, and vocoder.with RF, and PA module

3.2.2.4 Memory Part

The memory part is made up of a flash memory, SRAM for storing data.

\

Only for training and service purpose.

-20-

3.2.3 Circuit Description

3.2.3.1 Keypad/LCD and Receptacle Part

Once the keypad is pressed, the key signals are sent out to QSC6085 for processing. In addition, when the key is

pressed, the keypad lights up through the use of 2 LEDs and LCD backlights up. The status and operation of a

mobile station are displayed on the screen for the user with the characters and icons on the LCD.

Receptacle(CON4000) exchanges audio signals and data with external sources and external power.

Battery Connector receives power from the battery.

3.2.3.2 QSC Part

The baseband circuits and system software incorporate a low-power, high-performance

RISC microprocessor core featuring the ARM926EJ-S™ CPU and Jazelle™ accelerator

circuit from ARM® Limited. There are two low-power, high-performance QDSP4000™

digital signal processor (DSP) cores, one for the modem and one for applications. Camera

functions are supported by the QSC6030 device only, and MIDI and MP3 functions are

supported by the various QSC tiers as indicated in Table 1-2.

The baseband function reduces part costs by using two external bus interfaces to support

next-generation memory architectures such as NAND FLASH, SRAM and pseudo SRAM

(PSRAM), page and burst mode NOR or MLC NOR FLASH. The EBI2 also serves as an

enhanced LCD interface.

A variety of connectivity options are supported: the keypad interface and USB, UART, and

RUIM ports are available.

A camera interface is provided; this feature is available in the QSC6030 device only (not

the QSC6085 or QSC6085 devices).

Audio support supplements the analog/RF function’s CODEC, including up to

32- polyphonic MIDI in the QSC6085 device, MP3, AAC and AAC+ decoding support in

the QSC6085 and QSC6030 devices and additionally a Compact Media Extension

(CMX™)/MIDI synthesizer, and QCELP®.

The CDMA air interfaces mentioned earlier are implemented on the baseband CDMA

processor. All necessary interfaces to the RF functions are provided, some using a portion

of the 57 GPIOs. Many of the AMSS-configurable GPIOs are available for alternate uses

as desired by the wireless product designers.

Support circuitry and baseband internal functions include security, clock generation and

distribution, JTAG/ETM test interfaces, mode and reset controls, and the Q-fuse.

3.2.3.3 Audio Processing Part

Only for training and service purpose.

-21-

MIC signals are inputted into the audio codec, and amplified with programmable gain, and converted into digital

signals(PCM). Then, they are inputted into QSC6085.

In addition, digital audio signals(PCM) outputted from QSC6085 are converted into analog signals after going

through the audio codec. These signals are amplified with programmable gain on codec’s internal AMP and

external MIDI Synthesizer, transferred to the ear-piece.

3.2.3.4 Memory Part

The memory part consists of a 2Gbits Flash Memory and a 1Gbits SRAM. On the Flash Memory, there are

programs used for the operation of a mobile station and the non-volatile data of the mobile station such as a

ESN(Electronic Serial Number) are stored. The programs can be changed through down loading after the

assembling of mobile stations. On the SRAM, data generated during the operation of a mobile station are stored

temporarily.

3.2.3.5 Power Supply Part

When the battery voltage (+4.2V) is fed and the PWR key of keypad is pressed, the power-up circuitry in

QSC6085(U2000) is activated by the PWR_ON_SW/ signal, and then the LDO regulators embedded in

QSC6085 are operated and +1.2V_MSMC, +2.6V_MSMP and +2.65V_MSMA are generated.

3.2.4 Logic Part

The Logic part consists of internal CPU of QSC6085, MCP (SRAM+FLASH ROOM).

The QSC6085 receives X-tal(19.20MHz) clock signals, and then controls the phone during the CDMA mode.

The major components are as follows:

Only for training and service purpose.

-22-

CPU : ARM926EJ-S microprocessor core

MEMORY :

FLASH ROM + STATIC RAM : 2Gbits + 1Gbits (U3000, TYA000B001BLKF40)

•

CPU

The ARM7TDMI 32-bit microprocessor is used and CPU controls all the circuitry. Some of the features of the

ARM microprocessor include a 3 stage pipelined RISC architecture, both 32-bit ARM and 16-bit THUMB

instruction sets, a 32-bit address bus, and a 32-bit internal data bus. It has a high performance and low power

consumption.

FLASH ROM and SRAM

Flash Memory is used to store the program of the mobile station. Using the down-loading program, the

program can be changed even after the mobile station is fully assembled.

SRAM is used to store the internal flag information, call processing data, and timer data.

KEYPAD

For key recognition, key matrix is setup using KEY_SENSE[0]-[4] signals and GPIO of output ports of

QSC6085. 2 LEDs and backlight circuitry are included in the keypad for easy operation in the dark.

LCD MODULE

LCD module contains a controller which will display the information onto the LCD by 16-bit data from the

QSC6085. It is also supplied stable 1.8V_MSM_E1 by inner regulator in U2000 for fine view angle and and

LCD reflects to improve the display efficiency.

Only for training and service purpose.

-23-

CHAPTER 4. Trouble shooting

QSC6020

4.1 Rx Part Trouble

4.1.1 When Rx Power isn’t enough

Test Points

QSC6020

RX SAW

Checking Flow

QSC6085

START

Rx TEST SETUP(HHP)

- Test Channel : 610

E5515C Setup

- CH : 610

- Sector Power : -30 dBm Spectrum Analyzer Setting Oscilloscope Setting

Mobile S/W

Duplexer

TCXO

QSC020

4.Check

Control Signal

1.Check

TCXO Circuit

2.Check

Duplexer

Mobile SW

3.Check LNA, RX SAW

- 24 -

Re download SW, CAL

4.1.2 Checking TCXO Circuit

U201

Test Points

Waveform

U1007 Pin3

(TCXO)

U1007 Pin4

(+2.85V_TCXO)

Checking Flow

Pin 3

19.2MHz OK?

NO

Pin4

2.85V OK?

NO

Re download

YES

Replace U201

- 25 -

4.1.3 Check Mobile S/W & Duplexer

Dupl

Rx TEST SETUP(HHP)

YES

Test Points

Checking Flow

Check DP2 Pin6

- Test Channel : 610(DCN)

E5515C Setup

- CH : 610(DCN)

- Sector Power : -30 dBm Spectrum Analyzer Setting Oscilloscope Setting

Level is Appear?

YES

NO

Replace DP2

DP1000 Pin6

(L103)

U101

M/S

DP100

exer

Redownload SW and

Recalibration

- 26 -

Test Points

Waveform

DP1000 Pin 6

Figure 6

- 27 -

4.1.4 Checking LNA & SAW (DCN)

Rx TEST SETUP(HHP)

YesNoRx I/Q data Signal

Test Points

L1005 Pin

LNA_OUT_C_LB

Checking Flow

Waveform

- Test Channel : 610(DCN)

E5515C Setup

- CH : 610(DCN)

- Sector Power : -30 dBm Spectrum Analyzer Setting Oscilloscope Setting

Check SAW, F1002

Pin 3,4 (L1011,L1012)

MIX_INP_C_LB

Detected Signal?

Yes

See next Page to check

F1002 Pin3

F1002 Pin4

MIX_INM_C_LB

Changing F1002

- 28 -

4.1.5 Check PAM Circuit

U1005 Pin2

U1002 Pin2

Test Points

U1005 Pin 1,8

(Vcc, C1008)

(RF_OUT, L1006)

(RF_IN, C1030)

U1005 Pin4

(Vref, Q1000)

F1003 TX_SAW

- 29 -

LG KV600 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual