Pantech PG-1400 User manual

PG-1400 Service Manual PG-1400
PG-1400 Service Manual
(GSM Cellular Phone)
Pantech Co., Ltd., Korea
September 5, 2005
1st Edition
For Use by Authorized Service/Maintenance Personal Only
Documents to Receive This Addendum:
PG-1400 Maintenance/Repair/Operating Manual

PG-1400 Service Manual
CONTENTS
SECTION 1 INTRODUCTION .............................................................................................................3
1.1 AN INTRODUCTION OF GSM DIGITAL CELLULAR MOBILE COMMUNICATION SYSTEM...........................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
3.4 CAMERA MODULE……………………………….…….………….……………………………….…..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
4.1.7 CAMERA MODULE
4.2 RADIO TRANSCEIVER SECTION.....................................................................................................12
4.2.1 DC DISTRIBUTION AND REGULATION PART .................................................................................13
4.2.3 RECEIVER SECTION………………………………………………………………….…………….…13
4.2.3.1 AN OVERVIEW OF RECEIVE SECTION.......................................................................................13
4.2.3.2 RECEIVER PART……………………………………………………………………………….……14
4.2.4 TRANSMIT SECTION ..................................................................................................................15
4.2.4.1 AN OVERVIEW OF TRANSMIT SECTION ....................................................................................15
4.2.4.2 TRANSMITTER PART...............................................................................................................16
4.2.5. VCTCXO(VOLTAGE CONTROLLED TEMPERATURE COMPENSATED CRYSTAL OSCILLATOR):…….……16
SECTION 5 ALIGNMENT PROCEDURE..........................................................................................17
5.1 RECOMMENDED TEST EQUIPMENT................................................................................................17
5.2 CONNECTION OF TEST EQUIPMENT...............................................................................................17
SECTION 6 EQUIPMENT REPAIR PROCEDURE ...........................................................................18
6.1 NO POWER ON WITH BATTERY APPLIED ..........................................................................................18
6.1.1 POWER CHECK.........................................................................................................................18
6.1.2 OSCILLATION CHECK ................................................................................................................24
6.1.3 KEYPAD LED NOT IN OPERATION ...............................................................................................25
6.1.4 LCD BACKLIGHT LED NOT IN OPERATION(WHITE)..…………………………………………….. …26
6.2 AUDIO PART(EARPIECE,HANDS FREE EARPHONE,MICROPHONE,HANDS FREE MIC) ..................27
6.2.1 NO RECEIVING TONE HEARD (EARPIECE)..................................................................................27
6.2.2 NO RECEIVING TONE HEARD (HANDS FREE EARPHONE).............................................................28
6.2.3 SIDETONE NOT TRANSMITTED (EARPIECE)................................................................................29
6.2.4 SIDETONE NOT TRANSMITTED (HANDS FREE MIC) .....................................................................30
6.2.5 HOOK SWITCH NOT WORKING ..................................................................................................31
6.2.6 MELODY NOT RINGING.............................................................................................................32
6.2.7 VIBRATOR NOT WORKING …………………………………………………………………...…33
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6.3 SIM CARD PART ……………………………………...………………………….………………… 34
6.3.1 SIM ERROR ………………………………………………………………………….…..…………. 34
6.4 CHARGER PART………………….………………………………………………….…..………….. 35
6.4.1 CHARGING ERROR ……………….………………..……………………………….…………..…… 35
6.5 RF PART…………….………………….……………………………………………………………… 37
6.5.1 TEST CONDITIONS……………….…….…………………………………………… …………………37
6.5.2 POWER SUPPLY CHECK POINT….…….……………………………………………………………….38
6.5.3 POWER AMPLIFIER MODULE …….…….……………………………………………………………...40
6.5.4 VC-TCXO...…………...………………….……………………………………………………………..42
6.5.5 ANTENNA SWITCH MODULE…….………..…..…………………………………….…………………..43
6.6 FM RADIO MODULE……………….………..…..…………………………………….…………………..43
6.6.1 CHECK POINT POWER PART IN THE FM RADIO MODE ………..………..…..…………………………..43
6.6 2CHECK POINT COMMUNICATION PART IN THE FM RADIO MODE(INITIALIZATION,SET FREQUENCY)..…43
6.6.3 CHECK POINT OUTPUT PART IN THE FM RADIO MODE)…….………………………………………..…43
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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)
Conformance 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
1400, 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 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 1400 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) 1400 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) 1400 is designed to perform excellently even in the worst environment
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Section 2. Electrical Specifications
2.1 General E-GSM / DCS Band
Mobile Transmit Frequency 880 MHz ~ 915 MHz/1710MHz ~ 1785MHz
Mobile Receive Frequency 925 MHz ~ 960 MHz/1805MHz ~ 1880MHz
The Number of Time Slot 8
The Number of Channels 174/375
Channel Spacing 200 kHz
Power Supply Rechargeable Li-Ion Battery 3.7V/680mAh
Operating Temperature -10℃∼+55℃
Dimension
Weight
2.2 Transmitter E-GSM / DCS Band
Maximum Output Power 33±2 / 30±2 dBm
Frequency Error ±90Hz/±180Hz
Phase Error RMS < 5°, PEAK < 20°
Minimum Output Power 5±5 / 0±5 dBm
Power Control 5~19(2 dB Step)/0~15(2 dB Step)
Output RF Spectrum TS 100 910V6.2.0
Switching Transient TS 100 910V6.2.0
Intermodulation attenuation
Idle Mode
-57dBm 9KHz~880M/915MHz~1GHz
-59dBm 880MHz~915MHz
-53dBm 1.7~1.785GHz
-47dBm 1~1.715GHz/1.785GHz~12.75GHz
Conducted Spurious Emissions
Allocated Channel
-36dBm 9KHz~ 1GHz
-30dBm 1GHz~ 12.75GHz
2.3 Receiver
For GSM900 small MS :-102dBm
Reference Sensitivity
For DCS1800 class3 MS : -102dBm
C/Ic 9 dB
C/Ia1 -9 dB
C/Ia2 -41 dB
For Adjacent interference
For Adjacent(200KHz) interference
For Adjacent(400KHz) interference
For Adjacent(600KHz) interference
C/Ia3 -49 dB
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Section 3 Operation
3.1 Name of each part
Receiver Hall
1.5’ 65K CSTN
(128*128 pixels)
5 Way Menu
Joystick Key
Soft Key 2
Soft Key 1
End/ Power on, off
Clear Key
Numeric
Keypad
MIC Hall
Volume
u
p
/down
Speaker Hall
Camera key
330K CMOS
Camera
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Display(LCD)
Parameter Projected Actual(MAIN LCD)
Display Color CSTN LCD with white LED back lighting
1.5” 65k colors
Pixels : 128*128 pixels
Character : (font size :12/14/16) 8characters x 10lines(max)
Driver S6B33B9 (SAMSUNG Electronics.)
Module Dimen. 36(W) x 48.2(H) x 5.2(D) mm
Effective Area 27.26(W) x 34.07(H) mm (1.8 inch)
Number of Pixel 128(W) x RGB(W)x 160(H) pixel
Pixel pitch 71(W) x 213(H) um
3.3 Keypad
Market Goal Projected Actual Comments
English
Keypad
0-9, *,#
Send (Color)
End/Pwr (Color)
Up, Down, WAP
Soft1, Soft2, CLR
Camera
* Key: Vib. Mode
# Key: Auto Lock
0/+Key: international
2 Volume Keys
0-9, *,#
Send (Color)
End/Pwr (Color)
Up, Down, WAP
Soft1, Soft2, CLR
Camera
* 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
3.4.Camera Module
Product Name MC020A-0AA0AO
Effective pixel array 640 x 480
Unit Pixel size 3.6um x 3.6um
Module size 6.8mm x 6.8mm x 4.8mm
Operating voltage 2.8V
Weight 0.5g or below
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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”. AD6537B(U201) 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 AD6527 ARM7 microprocessor-combined DBB(Digital BaseBand)
GSM-ASIC, COMBO(flash ROM & SRAM), AD6537B ABB(Analog BaseBand) Chip. AD6527 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) AD6527 : U101, [ARM7 Processor Core + DBB GSM Signal Processing] ASIC
2) AD6537B : U201, Analog Baseband Processor (Power management + Voice Codec)
3) COMBO MEMORY(Flash ROM : U509, 128Mbit Flash Memory + 32Mbit SRAM )
4.1.2.2 Baseband Digital Signal Processing
AD6527 is a GSM core device containing ARM7 CPU core. AD6527 is 204 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
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☞Configuration by Function of AD6527
1 Microprocessor Core
AD6527 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 AD6527 to operate.
2) VC-TCXO(26 MHz) , 32.768KHz Clock:
This is the system reference clock to control SLEEP mode.
This is the clock derived from 26MHz 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:
AD6537B 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 ABB through a dedicated receive path serial port.
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4 RF Interface
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 sends Ramp 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 AD6537B 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 AD6527 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 128Mbit(16MByte). 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
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SRAM has a capacity of 32Mbit(4MByte) and stores system parameters, data buffer, and stack of
each task in it.
3 Key Tone Generation
All alert signals are generated by the DSP and output to the ABB audio output.
These alert can be used for the earpiece.
4.1.4 Notification Part
The notification of incoming call is given by melody, vibrator.
1) Melody:
This is a device sounding alert/melody tones.
The melody datas are stored in flash memory (U509) And generated by Melody IC(U301).
2) Vibrator:
This is a device enabling vibration. The vibrator data is stored in flash memory(U509)
And generated by K18(GPIO_3)pin.
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 output ports of KEYPADCOL(0-4). Also, to use the key even at light, the
backlight circuit is provided for LED 17s.
4.1.6 LCD Module(Display Part)
LCD module consists of LCD, controller, LED-Backlight, Indicator and Vibrator Driver IC.
LCD: 1S/W Icon x 1 lines[(128x3)x160] 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.
4.1.7 CAMERA Module
Camera Module is activated by keypad sw125.
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4.2 Radio Transceiver Section
Fig.4-1. RF Transceiver block diagram
The PG-1400’s RF Transceiver, which is Aero II, is the industry's most integrated RF front end for
multi-band GSM/GPRS digital cellular handsets and wireless data modems. The high-level of
integration obtained through patented and proven design architectures, fine line CMOS process
technology, and high-performance quad flat no-lead (QFN) technology results in a transceiver
solution with industry-leading performance, the smallest form factor, the fewest number of
components, the smallest solution footprint, and the lowest bill of materials (BOM) in the industry. A
quad-band RF front end using the Aero II transceiver can be implemented with 19 components in less
than 1 cm2of board area. This level of integration is an enabling force in lowering the cost, simplifying
the design and manufacturing, and shrinking the form factor in next-generation GSM/GPRS voice and
data terminals. The receive section uses a digital low-IF architecture that avoids the difficulties
associated with direct conversion while delivering higher performance, lower solution cost, and
reduced complexity. The baseband interface is compatible with any supplier's baseband The transmit
section is a complete up-conversion path from the baseband subsystem to the power amplifier, and
uses an offset phase-locked loop (OPLL) with a The frequency synthesizer uses Silicon Laboratories'
proven technology that includes an integrated RF VCO, loop filter, and varactor. The unique integer-N
PLL architecture produces a transient response superior in speed to fractional-N architectures
without suffering the high phase noise or spurious modulation effects often associated with those
designs. This fast transient response makes the Aero II transceiver well suited to GPRS multi-slot
applications where channel switching The analog baseband interface is used with conventional GSM
baseband ICs (BBIC). The receive and transmit baseband I/Q pins are multiplexed together in a
4-wire interface. A standard three-wire serial interface is used to control the transceiver.
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While conventional solutions use SiGe, BiCMOS, or other bipolar process technologies, the Aero II
transceiver is Silicon Laboratories' third-generation transceiver to be implemented in a 100% CMOS
process. Silicon Laboratories’ focus on RF and analog mixed-signal CMOS design creates innovation
in integration, space savings, and fabrication cost. This further extends the cost savings and
extensive manufacturing capacity of CMOS to the GSM/GPRS market.
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. Si4210 RF Transceiver also use +2.8V DC voltage.
SKY77328Power Amplifier (U512) use battery voltage.
4.2.3 Receiver Section
4.2.3.1 An Overview of Receive section
Fig.4-6. Receiver block diagram
The PG-1400’s Aero II transceiver uses a digital low-IF receiver architecture that allows for the
on-chip integration of the channel selection filters, eliminating the external RF image reject filters, and
the IF SAW filter required in conventional superheterodyne architectures. Compared with
direct-conversion architectures, the digital low-IF architecture has a much greater degree of immunity
to dc offsets that can arise from RF local oscillator (RFLO) self-mixing, second-order distortion of
blockers (AM suppression), and device 1/f noise.
The digital low-IF receiver's immunity to dc offsets has the benefit of expanding part selection and
improving manufacturing. At the front end, the common-mode balance requirements on the input
SAW filters are relaxed, and the PCB board design is simplified. At the radio's opposite end, the BBIC
is one of the handset's largest BOM contributors. It is not uncommon for a direct conversion solution
to be compatible only with a BBIC from the same supplier in order to address the complex dc offset
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issues. However, since the Aero II transceiver has no requirement for BBIC support of complex dc
offset compensation, it is able to interface to all of the industry leading baseband ICs.
The receive (RX) section integrates four differentialinput low noise amplifiers (LNAs) supporting the
E-GSM 900 (925–960 MHz), DCS 1800 (1805–1880 MHz) bands. The LNA gain is controlled with the
LNAG bit.
A quadrature image-reject mixer downconverts the RF signal to a low intermediate frequency (IF).
The mixer output is amplified with an analog programmable gain amplifier (PGA) that is controlled
with the AGAIN bits. The quadrature IF signal is digitized with high resolution analog-to-digital
converters (ADCs). The ADC output is downconverted to baseband with a digital quadrature local
oscillator signal. Digital decimation and FIR filters perform digital filtering, and remove ADC
quantization noise, blockers, and reference interferers. The response of the FIR filter is
programmable to a flat passband setting and a linear phase setting. After filtering, the digital output is
scaled with a PGA, which is controlled with the DGAIN bits.
The LNAG, AGAIN, and DGAIN register bits should be set to provide a constant amplitude signal to
the baseband receive inputs.
Digital-to-analog converters (DACs) drive differential I and Q analog signals onto the BIP, BIN, BQP,
and BQN pins to interface to standard analog-input baseband ICs.
The receive DACs are updated at 1.083 MHz and have a first-order reconstruction filter with a 1 MHz
bandwidth. No special processing is required in the baseband for dc offset compensation. The receive and
transmit baseband I/Q pins are multiplexed together in a 4-wire interface (BIP, BIN, BQP, and BQN). The
common mode level at the receive I and Q outputs is programmable with the DACCM bits, and the fullscale level
is programmable with the DACFS bits.
4.2.3.2 Receiver Part
ASM (Antenna Switch Module)
ASM consists of Tx filter, having an antenna port, and dual configuration with the transmitting path
isolated from the receiving path. A signal receives from the antenna of frequency band which is
942.5±17.5MHz for GSM900 bands, 1842.5±37.5 MHz for DCS bands and transmits it to the saw
filter for each band. The Tx filter passes through the output signals of frequency band that is
897.5MHz ±17.5MHz for GSM950 bands, 1747.5±37.5 MHz for DCS bnads from the power
amplifier and transmits it to the antenna. The maximum insertion loss is about 1.5 dB for the
receiving bands at 25o C and about 1.5 dB for the transmitting bands at 25o C.
SAW Filter (BPF / Band select filter)
The F501 filter is for the GSM900 band signals which range 942.5±17.5MHz with low insertion
loss. And F2 filter passes the DCS bands that cover 1842.5±37.5 MHz. These filters degrade
other band signals with high passing loss of 30~60 dB. The EGSM, and DCS’s maximum insertion
loss is 2.6 dB
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4.2.4 Transmit Section
4.2.4.1 An Overview of Transmit Section
Fig.4-8. Transmitter block diagram
The transmit section consists of an I/Q baseband upconverter, an offset phase-locked loop (OPLL),
and two 50 Ωoutput buffers that can drive an external power amplifier (PA). One output is for the
E-GSM 900 (880–915 MHz) bands and one output is for the DCS 1800 (1710–1785 MHz) bands.
The OPLL requires no external filtering to attenuate transmitter noise and spurious signals in the
receive band, saving both cost and power. The output of the transmit VCO (TXVCO) is a
constant-envelope signal that reduces the problem of spectral spreading caused by non-linearity in
the PA. Additionally, the TXVCO benefits from isolation provided by the transmit output buffers. This
significantly minimizes any load pull effects and eliminates the need for off-chip isolation networks.
A quadrature mixer upconverts the differential in-phase (BIP, BIN) and quadrature (BQP, BQN)
baseband signals to an intermediate frequency (IF) that is filtered and which is used as the reference
input to the OPLL. The OPLL consists of a feedback mixer, a phase detector, a loop filter, and a fully
integrated TXVCO.
Low-pass filters before the OPLL phase detector reduce the harmonic content of the quadrature
modulator and feedback mixer outputs.
The transmit I/Q interface must have a non-zero input no later than 94 quarter bits after PDN is
asserted for proper operation. If the baseband is unable to provide a sufficient TX I/Q non-zero input
preamble, then the CWDUR bits can be used to provide a preamble extension.
The receive and transmit baseband I/Q pins are multiplexed together in a 4-wire interface (BIP, BIN,
BQP, and BQN). In transmit mode, the BIP, BIN, BQP, and BQN pins provide the analog I/Q input
from the baseband subsystem. The full-scale level at the baseband input pins is programmable with
the BBG[1:0] bits. The I and Q signals are automatically swapped within the Aero II transceiver when
switching bands. The transmit output path is automatically selected by the ARFCN bits and the
BANDIND bits.
4.2.4.2 Transmitter Part
A. 3 dB attenuator
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These passive components are adopted for PAM to operate in a stable output power.
B. ASM (Antenna Switch Module / built in LPF)
These filters pass through the signals of which frequency band of 880~915MHz,
1710MHz~1785MHz which is the transmit frequency of GSM, DCS system terminal, and it
suppresses other images and spurious frequencies when the terminal transmits GMSK
modulated frequencies.
C. Power AMP Module (PAM)
This device amplifies signals ahead of transmiting them through the antenna to provide a sufficient
RF power. It has amplification factor of 28dB and efficiency of about 49% typically in GSM900 band
and amplification of 20dB and efficiency of about 53% typically in DCS band.
4.2.5 VC-TCXO(Voltage Controlled Temperature Compensated Crystal Oscillator)
This is the mobile station’s reference frequency source. Its frequency is 26MHz, this signal is
applied to the XOUT Buffer in Si4210 and the XOUT Buffer provides the 13MHz system reference
clock.
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Section 5. Alignment Procedure
5.1 Recommended Test Equipment
Model No. Description Maker Remark
8960 GSM Mobile Station
Test Set Agilent Technologies
8593E Spectrum Analyzer Hewlett Packard
TDS 340A Oscilloscope Tektronix
FLUKE 87 Digital Multimeter Fluke
E3630A DC Power Supply Hewlett Packard
Others Accessory Interface Connectors
RF Connectors
5.2 Connection of Test Equipment
Fig.5-1. Test Set Configuration
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SECTION 6. Equipment Repair Procedure
6.1 No Power On with battery Applied.
6.1.1 Power CHECK
1. Check battery power : 3.5V~4.2V.
Battery Pack
Gnd
Terminal
2. Check to see if C202.1 or C205 pin voltage is same with battery power : CP100
CP100
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CP100
3. Check to see if U408.5,6 and R221 pin is same with battery power : CP101
CP101
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