I360 Mobile Phone Maintenance Manual v0.1
I360 Mobile Phone Maintenance
Manual
Lenovo Mobile Telecommunications Co., Ltd.
All information contained herein, including the text, diagrams, data,
graphics, images, methods and ideas, is the property of Lenovo Mobile
Communications Co., Ltd. and shall not be disclosed, copied,
duplicated, photographed and transferred in any way by any individual
and organization without the written approval of the Mobile
Communication Office of Lenovo Research Institute.
Lenovo Mobile Telecommunications Co., Ltd.
© 2005 All rights reserved
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 1 of 1
I360 Mobile Phone Maintenance Manual v0.1
Contents
Preface............................................................................................................................................3
1. Specifications....................................................................................................................................4
2 Working Principles......................................................................................................................................5
2.1 GSM System Description.................................................................................................6
2.1.1 General Introduction to Cellular Theory...............................................................................6
2.1.2 GSM Description .............................................................................................................6
2.1.3 Service Area................................................................................................................9
2.1.4 Baseband Block Diagram....................................................................................................10
2.2 GSM Processor and Voice Baseband Codec .................................................................................. 11
2.3 GSM Processor ..............................................................................................................................12
2.3.1 Mcu Chip.............................................................................................................................12
2.3.2 ABB chip.............................................................................................................................13
3. Disassembly .............................................................................................................................................14
3.1 Recommended tools.......................................................................................................................15
3.2 Disassembling Steps.......................................................................................................................15
4 I360 Assembly Steps..............................................................................................................................16
5 Troubleshooting ........................................................................................................................................16
5.1 Block Diagram of Troubleshooting................................................................................................16
5.2 Problem Identification and Maintenance................................................................17
5.2.1 Block Diagram and Modules Description...........................................................................17
5.2.2 Baseband troubleshooting ...................................................................................................20
5.2.3 RF Troubleshooting..........................................................................................................24
6. Engineering Mode....................................................................................................................................28
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 2 of 2
I360 Mobile Phone Maintenance Manual v0.1
Preface
I360 is a bar-style GSM (GPRS) WAP mobile phone developed by Lenovo
Mobile Telecommunications Co., Ltd.
Services for this product are divided into three levels:
1、 Level 1 is for elementary services. With no specialized
maintenance tools available, only empirical maintenance
service is offered. Usually a heat gun is not required, and an IC
problem cannot be solved. IC troubleshooting is offered only
when necessary with the manufacturer’s permission.
2、 Level 2 is intended to solve problems that cannot be solved at
level 1. If necessary, specialized maintenance tools can be used
such as the heat gun, electric soldering iron, oscilloscope and
communications system analyzer. Any element of the phone
can be serviced at this level, and the service technicians will try
their best to solve various problems.
3、 Level 3 is for problems that cannot be solved at level 2. These
problems will be solved by the research and development
center of the manufacturer.
Important statement:
The target readers of this service manual are experienced technicians
familiar with similar devices. This manual is intended to technically assist
electronic and mechanical maintenance, suitable for I360 Level 2 maintenance
technicians. If the problems cannot be solved with the help of this manual,
please contact the Customer Support or the Development and Research Center
of Lenovo Mobile Telecommunications Co., Ltd. Thanks.
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 3 of 3
I360 Mobile Phone Maintenance Manual v0.1
1. Specifications
Table 1. Radio Frequency
Radio Frequency (900MHz)
Frequency range
Transmit: 880-915MHz；Reception:
925-960MHz
Bandwidth per channel 200 kHz
Number of channels
174 channels x8 (TDMA)
Carrier modulation GMSK (Gaussian Minimum Shift Keying)
Duplex bandwidth 45 MHz
Frequency stability
±0.1 ppm
Output power
33±2dBm - 5±5dBm
Reception sensitivity -104 dBm
Radio Frequency (1,800MHz)
Frequency range
Transmit: 1710-1785 MHz； Reception:
1805-1880 MHz
Bandwidth/channel 200 kHz
Number of channels
374 x 8 (TDMA)
Carrier modulation GMSK (Gaussian Minimum Shift Keying)
Duplex bandwidth 95 MHz
Frequency stability
± 0.1 ppm
Output power
30±2dBm - 0±5dBm
Reception sensitivity -105 dBm
Ambient temperature
-10 -- +55℃
GPRS feature
GPRS CLASS 8
Table 2. Operation voltage
Operation voltage
Li-polymer battery DC 3.4-4.2 V
Table 3. Power consumption
Power consumption
Average operation current < 250 mA
Standby current < 9 mA
Talk time* 90--150min (When using 680mAH lithium
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 4 of 4
I360 Mobile Phone Maintenance Manual v0.1
battery)
Standby time*
60--80h (When using 680mAH lithium battery)
Data sharing with PC Supported (specialized transmission cable
required)
* Depends on the network used.
2 Working Principles
Baseband Structure
Block Diagram
Voice
band/Baseband
coder
Radio
receptio
n
GSM/GPRS
Processor
128Mbit
FALSH
Backlight
Displayer
Keypad
SIM
Data terminal
ada
p
tation
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 5 of 5
I360 Mobile Phone Maintenance Manual v0.1
2.1 GSM System Description
2.1.1 General Introduction to Cellular Theory
A cellular system differs from other wireless telephone systems by dividing the service
area into many contiguous cells, which enables more powerful call processing and higher
system utilization. Each cell contains a base station which is capable of transmitting and
receiving signals, and is allocated with a set frequency pair (channel) for duplex
communications. Covering a relatively small area, each cell requires lower transmission
power than other wireless systems. So in a cellular system, the wireless transmission over a
specific channel involves the cell containing this channel and the immediate neighbor cells.
And since a cell corresponding to a specific channel covers a limited small area (compared
with the area covered by the whole system), the same channel can be reused by another cell
which is far away enough. This makes it possible for multiple subscribers to use the same
channel separately within the same geographical region.
2.1.2 GSM Description
The GSM system utilizes digital wireless communications technology, which makes it
different from previous cellular systems. Compared with older analog systems, the GSM
system enjoys many advantages which include the following:
A. International Roaming -- Since the universal GSM specifications are adopted
internationally, subscribers can dial or answer an international call in any country with
GSM support.
B. Digital wireless interface – A GSM phone provides a complete digital link between
a base station and a subscriber. In other words, a GSM phone provides a digital link
into the switching center and the traditional PSTN.
C. Compatible with ISDN – As the digital communications specification adopted in
many countries, ISDN can be used to transmit voice and data over copper links. A GSM
phone can offer features similar to those of a ISDN phone.
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 6 of 6
I360 Mobile Phone Maintenance Manual v0.1
D. Security and privacy -- While analog calls can be easily intercepted by portable
wireless receivers, GSM calls are encrypted and transmitted digitally, which are of high
security.
E. High quality voice – Problems such as channel interference, switching interrupts
and attenuation are properly handled in the digital system, and error code correction
(reorganizing missed data) also helps to improve voice quality.
F. Efficiency -- The GSM system can utilize the frequency band more efficiently than
traditional analog systems.
As shown in Figure 2 given below, the area bounded by the bold line represents the
total area to be covered by the imagined system. The whole area is divided into multiple cells,
with a base station in each cell. The cells work with specific channels and connect the
wireless phone subscribers to the mobile switching center. A mobile phone can utilize any of
the channels of the system, which means the mobile phone can be used in any of the cells.
Within any specific cell, the wireless communication requires lower power, so the channels
can be reused by cells which do not intersect with each other.
For instance, in Figure 2, cell A utilizes channels 1--8, cell B utilizes channels 9--16,
cell C utilizes channels 17--24, and cell D utilizes channels 1--8 again. So channels 1--8 are
used repeatedly, which means subscribers in cell A and cell D can use channels 1--8
simultaneously.
This frequency multiplexing increases the calls processing capability of the wireless
system, and it is unnecessary to increase the number of channels available. When the same
frequency is multiplexed within a community, the interference between the channels cannot
CELL A
CHANNELS
1-8
CELL B
CHANNELS
9-16
CELL C
CHANNELS
17-24
CELL D
CHANNELS
1-8
CELL F
CHANNELS
17-24
CELL E
CHANNELS
9-16
Figure 2: Hypothetical
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 7 of 7
I360 Mobile Phone Maintenance Manual v0.1
be ignored. The GSM system is more capable of enduring inter-channel interference. With
digital modulation, forward correction and equalization, GSM cells are more adjacent to each
other than similar analog cells. So frequency multiplexing improves the GSM system and
enables more powerful calls processing for frequently used areas.
Combined with Time Division Multiple Address (TDMA) technique, the same carrier
can be shared by multiple calls. A carrier is divided into several continuous TDMA frame
streams. And a frame is divided into 8 time slices. For each connection, a specific time slice
is assigned to each subscriber in each TDMA frame. Subscriber’s voice and data are
transmitted digitally and divided into several segments. subscriber’s data segments are
transmitted within the corresponding time slices as burst pulses.
The segments are modulated onto carriers via Gaussian Minimum Shift Keying
(GMSK). Phase Shift Keying (PSK) is a very effective modulation scheme. Different
frequencies can be used whenever a data pulse is transmitted, and this procedure is called
frequency-hopping, which helps reducing impact of the attenuation and improves the security
and privacy of the wireless connection. A GSM wireless call demands to transmit the
corresponding pulse in each frame, but the pulses may not be transmitted continuously. So
the unit should be made more efficient.
When a mobile phone is moved from one cell to another cell, measures should be taken
to reduce the inconvenience as much as possible to the subscriber. During the movement, the
signal strength of adjacent cells should be measured, and the channel quality should be
judged by the mobile phone and the base station. Cross-cell switching requirements should
be clearly defined, and the switching should be carried out before the voice quality over a
channel has fallen down to a sensible extent.
When a mobile phone is located at the center of a cell, the signal is very strong; when the
phone is moved to the edge of the cell, the signal turns weak. The information contained in
the signal indicates the distance between the subscriber and the base station. When a mobile
phone is moved from one cell to another cell, the base station of the new cell takes over the
control of this phone. The treatment of the distance changes between the mobile phone and
the base station are completely transparent to the subscriber.
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 8 of 8
I360 Mobile Phone Maintenance Manual v0.1
2.1.3 Service Area
Calls within the service area can be positioned and received by the system administrator
(for a wireless system, there are no definite geographical boundaries.) If a mobile phone is
located outside of the coverage area, Out of Service will be prompted, and the phone cannot
locate and receive a call. If the movement occurs during a call, the current call would abort.
For some special service area, there may be communications interrupts for some part of the
area.
The mobile phone’s identity information is kept in the Host Location Register (HLR)
and Visiting Location Register (VLR) of the local GSM system. VLR contains identity
information of all wireless phones enabled locally. When roaming into another mobile
communications network, the identity information of a mobile phone will be sent to the VLR
of the new network. The new network will carefully check the identity information. Once the
authenticity is verified, roaming features will be enabled.
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 9 of 9
I360 Mobile Phone Maintenance Manual v0.1
2.1.4 Baseband Block Diagram
Radio frequency block diagram
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 10 of 10
I360 Mobile Phone Maintenance Manual v0.1
2.2 GSM Processor and Voice Baseband Codec
2.2.1 Mcu chip consists of some elements, including ARM7TDMI microcontroller,
which is in charge of channel coding/decoding and running protocols and applications; a
16-bit digital signal processor (DSP), which produces full speed and enhanced full speed
voice and a high performance, soft decision Viterbi equalizer, which is built-in software
in the DSP. The ARM7TDMI microcontroller runs protocols at layers 1, 2 and 3, and
executes the human-machine interface software.
2.2.2 The ABB chip performs audio and baseband A/D and D/A conversion, acting
as an interface to the digital elements of the chipset and to the speaker and wireless
module. The auxiliary converters in the ABB chip are used for burst pulses control,
automatic frequency control, automatic gain control, as well as battery and temperature
monitoring.
The power management unit of the GSM phone is also built in the ABB chip,
which contains 5 LDOs, one of which controls the power supply to some key
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 11 of 11
I360 Mobile Phone Maintenance Manual v0.1
sub-modules (the SIM converter, SIM voltage converter for 3V-5V logic signals).There
are also some improvements in the control of recharging power increasing and of the
recharging progression.
2.3 GSM Processor
2.3.1 Mcu Chip
The enhanced GSM processor is a highly integrated core element in the
GSM chipset. The GSM processor features all base-band functions of the layer
1 protocols, including:
A. Complete Single Chip GSM Processor
B. Channel Codec Subsystem
a. Channel Coder/decoder
b. Interleaving/de-interleaving
c. Encryption/decryption
d. Control processor
d. 32-bit microcontroller(ARM7TDMI)
C. Serial and parallel display interfaces
D. Keyboard interface
E. EPROM interface
F. SIM interface
G. ABB interface
H. Wireless control subsystem
I. Programmable backlight
J. Real-time clock with alarming function
K. DSP subsystem
a. 16-bit solid-state coding
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 12 of 12
I360 Mobile Phone Maintenance Manual v0.1
b. Full-speed voice coding/decoding
b. Enhanced full-speed voice coding/decoding
d. 16-state Viterbi equalizer (soft decision)
e. Dual-tone multiple frequency and call progression voice producer
L. Wireless transmission power management
M. Delayed clock for low current standby state
N. Ultra-low power design
O. 14.4Kbps on-chip GSM data processing
P. JTAG testing interface
Q. 1.5V operation voltage
R. 179-pin BGA package
S. Voice baseband Codec and A/D interface
2.3.2 ABB chip
A. Power Voltage: 1.5V--3.3V
B. Input frequency of system clock: 13MHz
C. Ambient temperature: -40--85℃
D. Complete interfaces:
a. A/D interfaces for voice I/O
b. A/D interfaces for baseband I/O
c. A/D interfaces for auxiliary/control signals
E. Voice Codec
a. Complete linear Codec
b. Dual-channel 15-bit A/D converter with filters
c. Dedicated buzzer output
d. Programmable I/O gain
e. Serial audio interface
F. Baseband Codec
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 13 of 13
I360 Mobile Phone Maintenance Manual v0.1
a. Differential I, Q I/O
b. Burst pulse storage on chip
c. GMSK modulator
d. 2 10-bit D/A converters
d. 2 15-bit A/D converters
f. Limited pulse response filter on chip
g. Serial baseband interface
G. Auxiliary components
a. Support for automatic gain control, automatic frequency control and power slope
control
b. 10-bit automatic gain control D/A converter
c. 13-bit automatic frequency control D/A converter
d. 10-bit slop D/A converter with a 4x repeater
e. On-chip slop random memory
f. 4 channel 10-bit A/D converter
g. Serial auxiliary interface
h. Charger interface
i. 3V/5V SIM interface
j. Power management module
H. 100 Ball BGA package
3. Disassembly
The disassembly of bar phone I360 is relatively complicated. To avoid
internal elements and the housing damage when disassembling or assembling
again, the service operations should be performed with great caution. Safe
grounding should be guaranteed. When maintaining these elements, high
resistance anti-static bracelets must be used to prevent possible damage caused
by static electricity.
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 14 of 14
I360 Mobile Phone Maintenance Manual v0.1
Attention Most of the circuit elements of this device are prone to static
damage. When operating, transporting the device or maintaining the
internal elements, measures should be taken against static electricity.
3.1 Recommended tools
The following tools are recommended for disassembling or assembling the
mobile phone (or similar tools with the same functionality can be utilized).
a. Anti-static pad (including the grounding lead)
b. Anti-static bracelets
c. Rotary screw driver (Type T5，with a torque of 0.15Nm）
d. Ф1.4mm cross screw driver
e. Nipper
f. Chock gauge（100mm in length）,type: 0.02mm-1.00mm (the mesne thickness
is 0.4mm )
g. Digital multimeter
h. Oscilloscope
i. Electric soldering iron
j. Heat gun
j. Communications system analyzer
3.2 Disassembling Steps
The steps for assembling components of the mobile phone are described
as below. Disassembling can be done with the reversed steps.
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 15 of 15
I360 Mobile Phone Maintenance Manual v0.1
4 I360 Assembly Steps
Fig. 4-1 I360 assembly process
5 Troubleshooting
5.1 Block Diagram of Troubleshooting
Fault description by the user
Search for
a
solution from the
list given below
C
ause
d
by
hardware
D
own
l
oa
d
again
following the
steps give
n
b
elow
C
ause
d
by
software
Explain to the
use
r
Diagnosis
Notice: A brand new problem has to be solved based on the technician’s experience. The troubleshooting
list given below contains the known faults of I360, which is for Level 1 service reference.
5.1.1 Chips and elements inside the mobile phone are driven by weak currents, so the maintenance
should not be performed within a magnetic field or with high voltage to avoid possible
damage caused by heavy current.
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 16 of 16
I360 Mobile Phone Maintenance Manual v0.1
5.1.2
When troubleshooting the mobile phone, follow the general operation rules. Firstly
the measurement meters should be correctly connected. Then turn on and properly configure
the meter. The type of the fault should be firstly determined as well as the possible extension
of the fault.
5.1.3
The mobile phone is an integrated microelectronics product with delicate elements
inside, so the service technician should get familiar with the chips/elements and their
specifications before any troubleshooting operation, with the logic between the chips clear in
mind. During the troubleshooting, circuit analysis, careful inspection, correct judgment, as
well as quick and accurate operation are required to prevent any man-made malfunction and
economic loss. Repair operations should be performed after the type of the fault has been
confirmed.
5.1.4
Final Testing or Calling on Trial
Final testing or calling on trial are performed to check whether the mobile phone can
operate normally again.
5.2 Problem Identification and Maintenance
The I360 phone includes mainly a motherboard and a keypad board.When
troubleshooting the phone, check the connection between the LCD and the keypad board.
5.2.1 Block Diagram and Modules Description
5.2.1.1 Block Diagram
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 17 of 17
I360 Mobile Phone Maintenance Manual v0.1
DBB
ABB
MEMORY
JPEG
IC
CAMERA
LCM
SIM
BATTERY
RF
KEYBOARD
MIC
SPEAKER
EARPHONE
MIDI&
MP3
VIBRATOR
RECEIVE
5.2.1.2 Modules Description
Power supply: The upper part shows ABB’s direct output, and the lower part shows the output voltage
from the LDO. Once the phone is turned on, the LDO output should be valid. If there is no output, check
the LDO’s input and the shutdown control (which should be “1”).
V-DBB 1.5V TO DIGITAL CORE
V-FLASH 2.8V TO MEMORY
V-SRAM 2.8V TO MEMORY
V-IO 2.8V TO Peripherals
V-ABB 2.8V TO Analog Part
VBAT 3.5---4.2V Battery Voltage
Note: VBAT is connected directly with the battery, providing power supply to the phone
components via L301 (filter induce). The network name is VBA.
U336_5 pin 3.3V TO MIDI PA
U334_5 pin 1.8V TO MIDI
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 18 of 18
I360 Mobile Phone Maintenance Manual v0.1
U335_5pin 2.8V TO LCD,JPEG,MIDI
U318_4pin/ U318_6pin 2.8V/1.8V TO Camera Connector
VCHG (J305_3,4pin) 5.00~5.50V
Voltage from recharger to
the phone
U320 About 6.2V LCD Backlight Voltage(2
lights)
Connectors (both internal and external)
J305
18pin＋4pin connector, external
Recharging, download and
battery connection
J306
Earphone jack, external Earphone for receiving
calls or listening to MP3
music
J301
SIM slot, external For SIM connection
J304
MIC connector, internal For MIC connection
J320
Camera connector, internal For camera connection,
20pinB-B
J332
Motor connector, internal For motor connection
J308
Speaker connector, internal For speaker connection
Receiver
Receiver connector, internal
For receiver connection
J300
LCD connector, internal For LCD connection
Display (LCD and camera)
The display module primarily includes the JPEG chip (U301), LCD displayer, camera, and LCD backlight
driver (U320).
The clock signal (13MHz, 2.8V) of JPEG is provided by DBB.
The voltage of LCD is 2.8V, provided by pins 28,29,30 of J300. The data and control signals are provided
by the JPEG chip to the LCD, which includes data, chip-select and read/write pins.
Camera data signals are connected with the JPEG chip, including I2C, field synch and YUV. The power
supply is provided by U318. Pins 1 and 3 (control) of LDO are controlled by JPEG. When the camera is
not used, there is no output for LDO, and pin 1 is “0”.
Storage (composed of combFlash)
combFlash(U331) consists of 128Mb Flash and 32Mb SRAM, which are both connected directly with
DBB.
Music (consisting of MIDI, MP3 chip and peripheral circuits)
U333 (VC0938D)
provides MIDI and MP3 features. The Speaker signal is output directly by VC0938D
(with built-in mono audio PA)
，and the earphone can be used for playing MP3 music and receiving calls,
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 19 of 19
I360 Mobile Phone Maintenance Manual v0.1
so there is an analog switch U300.
5.2.2 Baseband troubleshooting
The possible symptoms and corresponding solutions of I360 are listed in the table below
for reference.
Entry
Symptoms Possible causes Solution or maintenance steps
The voltage between the
positive and negative
connectors of the battery is
0.4—0.6V when the battery
is removed.
1、Use the nipper to short-circuit the
positive and negative connectors.
Then check whether the voltage
has turned to be 0V.
2、 If the phone still cannot be turned
on, remove the battery. After about
ten minutes, install the battery
and try to turn on the phone.
The battery is not correctly
installed.
Install the battery again. Make sure
the clamp functions correctly.
The battery is low(less than
3.4V)
Recharge the battery for about 20
minutes, and then check the phone
display which should indicates the
battery level.
If there is battery level indication,
press the Power key for about 2
seconds to see whether the phone
functions normally.
Battery connectors are of
poor elasticity.
Replace the battery connector J305.
1
The phone cannot
be turned on.
Power key malfunction Check the mechanical part of the
Power key and check the switch.
2
Breakdown
Error in program running. Remove and reinstall the battery, and
make sure the clamp functions
properly. Then power on the phone
again.
3
Date and time are
reset.
There is no backup battery in
the phone.
Please set up date and time after the
battery is reinstalled.
18
The alarm clock
(agenda) cannot
be set up
Menu options are not
properly configured.
See the part on Settings menus in your
user’s manual.
The LCD connector is not
ell connected with the
FPC.
w
Reinstall it again.
5
Nothing
displayed on the
LCD.
Or the LCD is
b
acklighted, but
Check the soldering of FPC
connector J300.
Check for possible pseudo soldering
or bridging
LENOVO Lenovo Mobile Telecommunications Co., Ltd.（OPEN DOC） Page 20 of 20
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
Page is loading ...
/