Pantech G200 User manual

G200 Service Manual G200
G200 Service Manual
(GSM Cellular Phone)
Pantech Co., Ltd., Korea
January 19, 2008
1st Edition
For Use by Authorized Service/Maintenance Personal Only
Documents to Receive This Addendum:
G200 Maintenance/Repair/Operating Manual

G200 Service Manual
PANTECH R&D CONFIDENTIAL
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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……………………………………………………………………………….……16
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 ................................................................................................................29
6.1.3 KEYPAD LED NOT IN OPERATION(BLUE).....................................................................................30
6.1.4 LCD EL BACKLIGHT LED NOT IN OPERATION(WHITE)..………………………………………… …32
6.1.5 POWER INDICATED LED &STATUS LED ......................................................................................32
6.2 AUDIO PART(EARPIECE,HANDS FREE EARPHONE,MICROPHONE,HANDS FREE MIC) ..................34
6.2.1 NO RECEIVING TONE HEARD (EARPIECE)..................................................................................34
6.2.2 NO RECEIVING TONE HEARD (HANDS FREE EARPHONE).............................................................34
6.2.3 SIDETONE NOT TRANSMITTED (EARPIECE)................................................................................37
6.2.4 SIDETONE NOT TRANSMITTED (HANDS FREE MIC) .....................................................................37
6.2.5 HOOK SWITCH NOT WORKING ................................................................................................39

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

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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:
zTS 100 607-1 : Digital cellular telecommunication system(Phase2+)Mobile Station (MS) con
Formance specification Part1:Conformance specification
1.2 Frequency Allocation and Its Use
zTransmit frequency band : 880 MHz ~ 915 MHz(For EGSM) , 1710 MHz ~ 1785 MHz(For DCS)
zReceive frequency band: 925 MHz ~ 960 MHz(For EGSM) , 1805 MHz ~ 1880 MHz(For DCS)
zChannel spacing : 200 KHz
zARFCN(Absolute Radio Frequency Channel Number) : 1~124 and 975~1023 (For EGSM),
512~885 (For DCS)
zTransmit·receive frequency spacing: 45 MHz
zFrequency 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
925 MHz ~960 MHz : Base Transmit, Mobile receive
For DCS Band Fl(n)=1710.2+0.2*(n-512) 512 ≤n≤885 Fu(n)=Fl(n)+95
1710 MHz ~1785 MHz : Mobile Transmit,Base receive
1805 MHz ~1880 MHz : Base Transmit, Mobile receive

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** Fl(n)= frequency value of the carrier , Fu(n)= corresponding frequency value in upper band
1.3 Item Name and Usage
G200, GSM digital cell phone, is supercompact, superlight mobile communication terminal for
personal use. It has a 900MHz and 1800MHz frequency band and adopts GSM and DCS 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 snap-in antenna 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 G200 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) G200 adopts the Silabs’s AERO RF transceiver, which is CMOS RF front-end for multi-band
GSM digital cellular handsets. The Aero's 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) G200 is designed to perform excellently even in the worst environment