Pantech GB100 Service Manual

GB100 Service Manual GB100

GB100 Service Manual

(GSM Cellular Phone)

Pantech Co., Ltd., Korea

September 1, 2004

For Use by Authorized Service/Maintenance Personal Only

Documents to Receive This Addendum:

Edition

GB100 Maintenance/Repair/Operating Manual

GB100 Service Manual

CONTENTS

SECTION 1 INTRODUCTION .............................................................................................................3

1.1 INTRODUCTION ..............................................................................................................................3

1.2 FREQUENCY ALLOCATION AND ITS USE ...........................................................................................3

1.3 ITEM NAME AND USE......................................................................................................................4

1.4 CHARACTERISTICS.........................................................................................................................4

SECTION 2 ELECTRICAL SPECIFICATIONS....................................................................................5

2.1 GENERAL ......................................................................................................................................5

2.2 TRANSMITTER…………………………………………………………………………………………….5

2.3 RECEIVER…………………………………………………………………………………………………5

SECTION 3 OPERATION....................................................................................................................6

3.1 NAME OF EACH PART…..……………………………….…………………………………………………6

3.2.DISPLAY ..………………….…………………………….………………………………………………..7

3.3 KEYPAD …………………………………….………….………………………………………………..7

SECTION 4 THEORY OF OPERATION..............................................................................................8

4.1 LOGIC SECTION........................................................................................................................8

4.1.1 DC DISTRIBUTION AND REGULATION PART…………………………………………………………….8

4.1.2 LOGIC PART…………………………………………………………………………………………….8

4.1.2.1 SUMMARY…………………………………………………………………………………………….8

4.1.2.2 BASEBAND DIGITAL SIGNAL PROCESSING…………………………………………………………..8

4.1.3 MEMORY PART………………………………………………………………………………………..10

4.1.4 NOTIFICATION PART .................................................................................................................. 11

4.1.5 KEY PAD PART.......................................................................................................................... 11

4.1.6 LCD MODULE(DISPLAY PART)................................................................................................... 11

4.2 RADIO TRANSCEIVER SECTION.....................................................................................................12

4.2.1 DC DISTRIBUTION AND REGULATION PART .................................................................................13

4.2.2 TRANSCEIVER PIN DESCRIPTION…………………………………………………….……….14

4.2.3 RECEIVE SECTION………………………………………………………………………………….…17

4.2.3.1 AN OVERVIEW OF RECEIVE SECTION.......................................................................................17

4.2.3.2 RECEIVER PART……………………………………………………………………………….……18

4.2.4 TRANSMIT SECTION ..................................................................................................................19

4.2.4.1 AN OVERVIEW OF TRANSMIT SECTION ....................................................................................19

4.2.4.2 TRANSMITTER PART...............................................................................................................20

4.2.5 OFFSET PLL……………………………………………………………………………….…………..21

4.2.5.1 AN OVERVIEW OF OFFSET PLL............................................................................................21

4.2.5.2 VCTCXO(VOLTAGE CONTROLLED TEMPERATURE COMPENSATED CRYSTAL OSCILLATOR):V801….22

SECTION 5 ALIGNMENT PROCEDURE..........................................................................................23

5.1 RECOMMENDED TEST EQUIPMENT................................................................................................23

5.2 CONNECTION OF TEST EQUIPMENT...............................................................................................23

SECTION 6 EQUIPMENT REPAIR PROCEDURE...........................................................................24

6.1 NO POWER ON WITH BATTERY APPLIED ..........................................................................................24

6.1.1 POWER CHECK.........................................................................................................................24

6.1.2 OSCILLATION CHECK ................................................................................................................30

6.1.3 KEYPAD LED NOT IN OPERATION(3-COLOR AND BLUE) ..............................................................31

6.1.4 LCD EL BACKLIGHT LED NOT IN OPERATION(WHITE)..………………………………………… …33

6.2 AUDIO PART(EARPIECE, HANDS FREE EARPHONE, MICROPHONE, HANDS FREE MIC) ..................35

6.2.1 NO RECEIVING TONE HEARD (EARPIECE) ..................................................................................35

6.2.2 NO RECEIVING TONE HEARD (HANDS FREE EARPHONE).............................................................35

6.2.3 SIDETONE NOT TRANSMITTED (EARPIECE)................................................................................38

6.2.4 SIDETONE NOT TRANSMITTED (HANDS FREE MIC) .....................................................................38

6.2.5 HOOK SWITCH NOT WORKING ..................................................................................................39

6.2.6 MELODY NOT RINGING.............................................................................................................40

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

6.2.7 VIBRATOR NOT WORKING …………………………………………………………………...…41

6.3 SIM CARD PART ……………………………………...…………………………………………….42

6.3.1 SIM ERROR ………………………………………………………………………………………….42

6.4 CHARGER PART……………………………………………………………………………………..43

6.4.1 CHARGING ERROR ………………………………..…………………………………………………43

6.5 RF PART…………….………………………………………………………………………………… 45

6.5.1 TEST CONDITIONS………………………………………………………………… …………………45

6.5.2 POWER SUPPLY CHECK POINT……………………………………………………………………….46

6.5.3 POWER AMPLIFIER MODULE ………………………………………………………………………...48

6.5.4 VCTCXO...…………...………………………………………………………………………………..50

6.5.5 ANTENNA SWITCH MODULE……………………………………………………….…………………..51

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

SECTION 1. Introduction

1.1 An Introduction of GSM Digital Cellular Mobile Communication System

GSM (Global System for Mobile communication) concluded that digital technology working in

the Time Division Multiple Access (TDMA) mode would provide the optimum solution for the

future system. Specifically , a TDMA system has the following advantage

► Offers a possibility of channel splitting and advanced speech coding ,resulting in improved

spectrum efficiency.

► Offers much greater variety of service than the analog

► Allows considerable improvements to be made with regards to the protection of information.

The GSM system is basically designed as a combination of three major subsystem;

The network subsystem, the radio subsystem, and the operation support system.

The functional architecture of a GSM system can be divided into the Mobile Station (MS), the Base

Station (BS), and the Network Subsystem (NS). The MS is carried by the subscriber, the BS

subsystem controls the radio link with the MS and the NS performs the switching of calls between

the mobile and other fixed or mobile network users as well as mobility management. The MS and

the BS subsystem communicate across the Um interface also known as radio link

The specifications relating to MS are as follows:

z TS 100 607-1 : Digital cellular telecommunication system(Phase2+)Mobile Station (MS) con

Formance specification Part1:Conformance specification

1.2 Frequency Allocation and Its Use

z Transmit frequency band : 880 MHz ~ 915 MHz(For EGSM), 1710 MHz ~ 1785 MHz(For DCS)

1850 MHz ~ 1910 MHz(For PCS)

z Receive frequency band: 925 MHz ~ 960 MHz(For EGSM) , 1805 MHz ~ 1880 MHz(For DCS),

1930 MHz ~ 1990 MHz(For PCS)

z Channel spacing : 200 KHz z ARFCN(Absolute Radio Frequency Channel Number) : 1~124 and 975~1023 (For EGSM),

512~885 (For DCS), 512~810 (For PCS)

z Transmit·receive frequency spacing: 45 MHz(For EGSM),

z Frequency band and Channel Arrangement

For standard GSM Fl(n)=890+0.2*n 1 ≤n≤ 124 Fu(n)=Fl(n)+45

890 MHz ~915 MHz : Mobile Transmit,Base receive

935 MHz ~960 MHz : Base Transmit, Mobile receive

For Extended GSM Fl(n)=890+0.2*n 1 ≤n≤ 124 Fu(n)=Fl(n)+45

Fl(n)=890+0.2*(n-1024) 975 ≤n≤ 1023

880 MHz ~915 MHz : Mobile Transmit,Base receive

95MHz(For DCS), 80MHz(For PCS)

925 MHz ~960 MHz : Base Transmit, Mobile receive

For DCS Fl(n)=1710.2+0.2*(n-512) 512≤n≤885 Fu(n)=Fl(n)+95

1710 MHz ~ 1785 MHz : Mobile Transmit,Base receive

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

1805 MHz ~ 1880 MHz : Base Transmit, Mobile receive

For PCS Fl(n)=1850.2+0.2*(n-512) 512 ≤n≤ 810 Fu(n)=Fl(n)+80

1850 MHz ~1910 MHz : Mobile Transmit,Base receive

1930 MHz ~1990 MHz : Base Transmit, Mobile receive

** Fl(n)= frequency value of the carrier , Fu(n)= corresponding frequency value in upper band

1.3 Item Name and Usage

GB100, GSM digital cell phone, is supercompact, superlight mobile communication terminal for

personal use. It has a 900MHz, 1800MHz and 1900MHz frequency band and adopts GSM and

PCS mode having excellent spectrum efficiency, economy, and portability.

This product is GSM Cellular type portable phone, adopting 1-cell Li-ion battery and power saving

circuit to maximize its operation time. Also, it is equipped with a fixed antenna (snap-in type) and its

color LCD with font built in enables both Chinese and English text service. And power control(basic

feature of GSM), security feature, voice symbol feature, and variable data rate feature are used

appropriately to ensure its best performance. This product consists of a handset, battery pack, and

Travel charger.

1.4 Characteristics

1) All the active devices of GB100 are made of semiconductors to ensure excellent performance

and semi-permanent use.

2) Surface mounting device (SMD) is used to ensure high reliability, compactness and lightness.

3) GB100 adopts the Skyworks’s RF transceiver, which is CMOS RF front-end for multi-band GSM

digital cellular handsets. The Skyworks’s RF transceiver highly-integrated architecture

eliminates the IF SAW filter, low noise amplifiers (LNAs) for three bands, transmit and RF

voltage-controlled oscillator (VCO) modules, and more than 60 other discrete components found

in conventional GSM handsets to deliver smaller, more cost effective GSM solutions that are

easier to design and manufacture.

4) GB100 is designed to perform excellently even in the worst environment

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

Section 2. Electrical Specifications

2.1 General E-GSM / PCS Band

Mobile Transmit Frequency

Mobile Receive Frequency

The Number of Time Slot 8 The Number of Channels 174 / 374 / 299 Channel Spacing 200 kHz Power Supply Rechargeable Li-Ion Battery 3.7V/680mAh Operating Temperature

Dimension Weight 76 g

880 MHz ~ 915 MHz / 1710 MHz ~1785 MHz / 1850MHz ~ 1910MHz 925 MHz ~ 960 MHz / 1805 MHz ~ 1880 MHz / 1930MHz ~1990MHz

-10℃ ∼ +55℃ 76(H) ×40(W) ×23.5(D) mm (SLIM)

2.2 Transmitter E-GSM / PCS Band

Maximum Output Power Frequency Error Phase Error Minimum Output Power

Power Control

Output RF Spectrum TS 100 910V6.2.0 Switching Transient TS 100 910V6.2.0 Intermodulation attenuation

EGSM and DCS

Allocated a channel;

-36dBm 9kHz ~ 1GHz

-30dBm 1GHz ~ 12.75GHz

Idle mode;

-57dBm 9KHz ~ 1GHz

-47dBm 1GHz ~ 12.75GHz with the following excoptions

-59dBm 880MHz ~ 915MHz

Conducted Spurious Emissions

-53dBm 1.71GHz ~ 1.785GHz

-76dBm 1900 ~ 1920MHz, 1920 ~ 1980MHz, 2010 ~

PCS

Allocated Channel;

-36dBm 9KHz~ 1GHz

-30dBm 1GHz~ 12.75GHz

Idle mode;

-57dbm 9kHz ~ 1000MHz

-53dBm 1850MHz ~ 1910MHz

-47dBm 1GHz ~ 12.75GHz

33±2 / 30±2 / 30±2 dBm ±90Hz / ±180Hz / ±180Hz RMS < 5°, PEAK < 20° 5±5 / 0±5 dBm / 0±5 dBm 5~19(2 dB Step) ) / 0~15(2 dB Step) /

0~15(2 dB Step)

2025MHz, 2210 ~ 2170MHz

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

2.3 Receiver

For GSM900 small MS :-102dBm Reference Sensitivity

For Adjacent interference

For Adjacent(200KHz) interference

For Adjacent(400KHz) interference

For Adjacent(600KHz) interference

Section 3 Operation

3.1 Name of each part

For DCS1800 / PCS1900 class3 MS : -102dBm

C/Ic

C/Ia1 -9 dB

C/Ia2 -41 dB

C/Ia3 -49 dB

9 dB

Antenna

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

Two-mode Speaker

Display Screen

Mic

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

3.2 Display(Single LCD)

Parameter Projected Actual (MAIN LCD)

Display Color STN LCD with white LED back lighting

65,000 colors European Character : (font size : 16×16) 7 lines x 8 characters Chinese Character

: (font size : 16×16) 7 lines × 8 characters Driver HCD667A66UBP Module Dimen. 34.8(W) x 41.61(H) x 4.94(D) Active Area 28.868(W) x 28.868(H) Dot pitch 0.07(W) x 0.21(H)

3.3 Keypad

Market Goal Projected Actual Comments English

Keypad

0-9, *,# Send (Color) End/Pwr (Color) Up (Melody), Down (Phonebook), Left (My menu), Right (SMS) Center (WAP) MENU, OK, CLR

* Key: Vib. Mode # Key: Auto Lock 0/+Key: International

0-9, *,# Send (Color) End/Pwr (Color) Up (Melody), Down (Phonebook), Left (My menu), Right (SMS) Center (WAP) MENU, OK, CLR

* Key: Vib. Mode # Key: Auto Lock 0/+Key: International 2 Volume Keys

Meets Goal. (Industrial design sample required) Meets Goal

Keys for VR and Lock International Volume up/down

2 Volume Keys

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

Section 4. Theory of Operation

4.1 Logic Section

4.1.1 DC Distribution and Regulation Part

Applying battery voltage and pressing “END” key on the key pad short-circuits “Ground” and “ PowerON”. AD6535(U102) control that power manage regarding power on/off in handset Pressing POWERKEY on the key pad is active on the handset. This will turn on all the LDOs, when PowerON is held low. The power of RF Tx power amplifier is supplied directly by the battery.

4.1.2 Logic part

4.1.2.1 Summary

The logic part consists of AD6525 ARM7 microprocessor-combined DBB(Digital BaseBand)

GSM-ASIC, COMBO(flash ROM & SRAM), AD6535 ABB(Analog BaseBand) Chip. AD6525 is

GSM-ASIC chipset implemented for GSM terminal’s system control and baseband digital signal

processing.

Major parts used in the logic part are as follows:

1) AD6525 : U101, [ARM7 Processor Core + DBB GSM Signal Processing] ASIC

2) AD6535 : U102, Analog Baseband Processor (Power management + Voice Codec)

3) COMBO MEMORY(Flash ROM : U1, 64Mbit Flash Memory + 16Mbit SRAM )

4.1.2.2 Baseband Digital Signal Processing

AD6525 is a GSM core device containing ARM7 CPU core. AD6525 is 160 pin LFBGA (mini-BGA)

package, consisting of terminal chips. The function and characteristics of clock are as follows:

1) Complete single chip GSM Processor

2) Channel codec sub-system

• Channel coder and decoder

• Interleaver and Deinterleaver

• Encryption and Decryption

3) Control Processor Subsystem including

• Parallel and serial Display interface

• Keypad Interface

• SIM Interface

• Control of RADIO subsystem

• Real Time Clock with Alarm

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

☞ Configuration by Function of AD6525

1 Microprocessor Core

AD6525 has a built-in ARM7 microprocessor core, including microprocessor interrupt controller,

timer/counter, and DMA controller. And besides, 32bit data path is included, and up to 8Mbyte

addressing is enabled and can be extended up to 16Mbyte. Although external clock should be

provided to operate the microprocessor, this core uses 13MHz VCTCXO to provide clock.

2 Input Clock

1) Main Clock(13 MHz):

This is the clock needed for the microprocessor built in AD6525 to operate.

2) VC-TCXO(13 MHz) , 32.768KHz Clock:

This is the system reference clock to control SLEEP mode.

This is the clock derived from 13MHz VC-TCXO clock, provided by RF part. It is the timing

reference clock for GSM signal processing.

3 DSP Subsystem

This is a GSM signal processing part in GSM mode, consisting of speech transcoding and

Channel equalization as follows:

1) Speech transcoding

In full rate, the DSP receives the speech data stream from VBC and encodes data from 104kbps to

13kbps. Using algorithm is Regular Pulse Excitation with Long Term Prediction (RPE-LTP).

2) Equalization

The Equalizer recovers and demodulates the received signal

The Equalizer establishes local timing and frequency references for mobile terminal as well as

RSSI calculation.

The equlization algorithm is a version of Maximum Likelihood Sequency Estimation(MLSI)

using Viterbi Algorithm.

☞ GSM Core and RF Interface

1) Transmitter:

AD6535 ABB receive data at 270kbps and use an on chip lock-up table to perform GMSK modulation. A pair of 10bit matched differential DACs convert the modulated data and pass I and Q analog data to the transmit section of the radio system.

2) Receiver:

The receiver I and Q signals are sampled by a pair of ADCs at 270kbps.

The I and Q samples are transferred to the EGSMP through a dedicated receive path serial port.

4 RF Interface

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

This interfaces the RF part to control power amplifier, Tx LO buffer amplifier, VC-TCXO, and

AGC-end on transmit/receive paths in the RF part.

1) Transmitter Interface:

This transmits TX_AGC signal to Tx AGC amplifier to adjust transmit power level and sends

Ramp_DAC signal to the RF part to control power amplifier.

2) Receiver Interface:

This transmits RX_AGC signal to Rx AGC amp. to adjust receive path gain.

5 General Purpose ADC Support

The AD6535 includes a general purpose 10bit auxiliary ADC with four multiplexed input channel

These are used for measurment of battery voltage ID , temperature and accessory ID.

6 USC(Universal System Connector) Interface

A Typical GSM handset requires serial connections to provide data during normal phone operation

manufacturing,testing and debugging.

7 General Purpose Interface

The AD6525 provides 32 interface pin for control of peripheral devices. All GPIO pins start up as inputs. Additional purpose inputs and outputs are available under SW control.

8 Speech Transcoding

In full rate mode, the DSP receive the speech data stream from the ABB and encodes data from 104kbps to 13kbps.Using algorithm is Regular Pulse Exitation with Long Term Prediction as specified GSM Recommandation

9 Power Down Control Section

1) Idle Mode Control:

If IDLE/ signal turns ‘Low’, transmitter section becomes disabled.

2) Sleep Mode Control:

If IDLE/ and SLEEP/ signals turn ‘Low’, all the sections except for VC-TCXO circuit become

disabled.

3) Receiver & Transmitter Mode Control:

If IDLE/ and SLEEP/ signals turn ‘High’, all the sections become enabled to perform

transmit/receive operation.

4.1.3 Memory Part

Memory consists of COMBO (flash ROM & SRAM).

1 Flash ROM

Flash ROM has a capacity of 64Mbit(8MByte). The main programs of the terminal(call processing, user interface, and diagnostic task) and supplemental programs (NAM program and test program) are stored in the flash ROM. Even if the program version may be changed in the future, customers can download the program.

2 Static RAM

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

SRAM has a capacity of 16Mbit(2MByte) and stores system parameters, data buffer, and stack of each task in it.

3 Key Tone Generation

All alert signals are generated by melody IC output.

4.1.4 Notification Part

The notification of incoming call is given by melody, vibrator, and 7color-LED.

1) Melody:

This is a device sounding alert/melody tones.

The melody datas are stored in flash memory (U104) And generated by 6525 DBB internal DSP.

2) Vibrator:

This is a device enabling vibration. The vibrator data is stored in flash memory(U104)

And generated by C5(GPO_23)pin.

3) 7color-LED:

This is a device to indicate a notification mode using the lamp.

U101 Nos. H12, C9 and B8 signal drives the lamp to flash.

4.1.5 Key Pad Part

To enable key operation to input information, the key matrix is configured using strobe signal of

KEYPADROW(0-4) and 5 input ports of KEYPADCOL(0-4). Also, to use the key even at light, the

backlight circuit is provided for LED 6s.

4.1.6 LCD Module(Display Part)

LCD module consists of LCD, controller, LED-Backlight,

LCD: 1S/W Icon x 1 lines[(128x3)x128] can be displayed on the LCD panel. 6 icons could be

provided by S/W. Controller with English font built in has been used.

LED-backlight Using illuminates the LCD panel, and LCD reflector enhances LCD display effect.

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

4.2 Radio Transceiver Section

Fig.4-1. RF Transceiver block diagram

Fig.4-2. Top view of RF Transceiver PCB Layout

The RF Transceiver of GB100, which is AERO I , consists of the GSM transimitter, the GSM

Receiver, and the RF synthesizer. The highly integrated solution eliminates the IF SAW filter,

external low noise amplifiers (LNAs) for three bands,

transmit and RF voltage controlled oscillator

(VCO) modules, and more than 60 other discrete components found in conventional designs.

The receive section uses a digital low-IF architecture that avoids the difficulties associated with

PANTECH R&D CONFIDENTIAL

GB100 Service Manual

direct conversion while delivering lower solution cost and reduced complexity. The transmit section

is a complete up-conversion path from the baseband subsystem to the power amplifer (U701) and

uses an offset phase locked loop (PLL) with a fully integrated transmit VCO.

The frequency synthesizer includes integrated RF and IF VCO’s, Varactors, and Loop filters. The

unique integer-N PLL architecture produces a transient response that is superior in speed to

fractional architectures without suffering the high phase noise or spurious modulation effects often

associated with those designs.

4.2.1 DC Distribution and Regulation Part

The battery voltage, in return, is applied to the logic part and RF part via LDO(Low Drop-Out) regulator.

As several LDO regulators are used, power can be supplied for each necessary part efficiently.

Audio/Logic parts use +2.8V. SI4205 RF Transceiver(U501) and RF3133 Power Amplifer(U701) also

use +2.8V DC voltage.

4.2.2 Transciever pin description

Fig.4-3. Top View of Si4205

PANTECH R&D CONFIDENTIAL

+ 34 hidden pages