LG C3600 Service Manual

Table of Contents

1. INTRODUCTION .........................................................................................1

1.1 Purpose................................................................................................................ 1

1.2 Regulatory Information.........................................................................................1

2. SYSTEM SPECIFICATION..........................................................................3

3. C3600 TECHNICAL BRIEF .....................................................................4

3.1 C3600 Block Diagram...................................................................................... 4

3.2 RF Part................................................................................................................. 5

3.3 BaseBand Transmit Section................................................................................. 6

3.4 BaseBand Receive Section.................................................................................. 6

4. C3600 TROUBLE SHOOTING................................................................7

4.1 RF Components...................................................................................................7

4.2 RX Trouble...........................................................................................................8

4.2.1 Check ANT Feedback Points..................................................................... 8

4.2.2 Check Regulator Circuit............................................................................. 8

4.2.3 Check VCTCXO Circuit.............................................................................. 9

4.2.4 Check Antenna Switch & Mobile Switch....................................................10

4.2.5 Check SAW Filter......................................................................................11

4.2.6 Checking Receive IQ................................................................................12

4.3 TX Trouble ..........................................................................................................13

4.3.1 Check LDO Circuit....................................................................................13

4.3.2 Check VCTCXO Circuit.............................................................................13

4.3.3 Check Transmit IQ....................................................................................13

4.3.4 Check PAM Control Signal........................................................................14

4.3.5 Check Antenna Switch and Mobile Switch................................................15

4.4 Power On Trouble...............................................................................................15

4.5 Charging Trouble ................................................................................................17

4.6 LCD Trouble....................................................................................................... 19

4.6.1 LCD Blue Screen..................................................................................... 19

4.6.2 LCD Blank Screen or Abnormal Screen................................................... 19

4.7 Camera Trouble..................................................................................................20

4.8 Color LED Trouble ..............................................................................................21

4.9 KEYPAD Blacklight LEDS Trouble......................................................................22

4.10 SIM Trouble.......................................................................................................23

4.11 Ear Jack Trouble...............................................................................................24

4.12 Speaker/Receiver Trouble.................................................................................26

5. DOWNLOAD AND CALIBRATION .............................................................28

6. CIRCUIT DIAGRAM & PCB LAYOUT…………………………………………29

7. EXPLODED VIEW & REPLACEMENT PART LIST………………………….36

1. INTRODUCTION

1. INTRODUCTION

1.1 Purpose

This manual provides the information necessary to repair, calibration, description and
download the features of C3600.

1.2 Regulatory Information

A. Security

Toll fraud, the unauthorized use of telecommunications system by an unauthorized part
(for example, persons other than your company’s employees, agents, subcontractors, or
person working on your company’s behalf) can result in substantial additional charges for
your telecommunications services. System users are responsible for the security of own
system.There may be risks of toll fraud associated with your telecommunications system.
System users are responsible for programming and configuring the equipment to prevent
unauthorized use. The manufacturer does not warrant that this product is immune from
the above case but will prevent unauthorized use of common – carrier telecommunication
service of facilities accessed through or connected to it. The manufacturer will not be
responsible for any charges that are resulted from such unauthorized use.

B. Changes in Service

A local telephone company may make changes in its communications facilities or
procedure. If these changes could reasonably be expected to affect the use of this phone
or compatibility with the network, the telephone company is required to give advanced
written notice to the user, allowing the user to take appropriate steps to maintain
telephone service.

C. Maintenance Limitations

Maintenance limitations on this model must be performed only by the manufacturer or its
authorized agent. Therefore, note that unauthorized alternations or repair may affect the
regulatory status of the system and may void any remaining warranty.

D. Notice of Radiated Emissions

This model complies with rules regarding radiation and radio frequency emission as
defined by local regulatory agencies. In accordance with these agencies, you may be
required to provide information such as the following to the end user.

E. Interference and Attenuation

Phone may interfere with sensitive laboratory equipment, medical equipment, etc.
Interference from unsuppressed engines or electric motors may cause problems.

F. Electrostatic Sensitive Devices

1

1. INTRODUCTION

ATTENTION

Boards, which contain Electrostatic Sensitive Device (ESD), are indicated by the sign.

Following information is ESD handling:

• Service personnel should ground themselves by using a wrist strap when exchange
system boards.

• When repairs are made to a system board, they should spread the floor with anti-static
mat which is also grounded.

• Use a suitable, grounded soldering iron.

• Keep sensitive parts in these protective packages until these are used.

• When returning system boards or parts like EEPROM to the factory, use the protective
package as described.

2

2. SYSTEM SPECIFICATION

2. SYSTEM SPECIFICATION

Item Target Specification

Form Factor Folder Type
Standard Battery (1000mAh , Li-ion)

Size：34(W)×50(H)×5.5(T) mm

Weight：25g
Size 88 X 44 X 23mm
Weight 88.35 Gram(with standard battery)
Standby Current Below 4.5mA under the least current consumption

(e.g. Paging Period = 9)
Talk Time Up to 3 hrs (GSM Tx Lev:5)
Standby Time Up to 200 hrs : Paging Period 9, RSSI 85dBm
Antenna Internal
LCD

Back Light Blue LED
PC Sync Yes
Indicator LED None
Vibrator Yes (Cylinder Type)
Buzzer Yes
C-MIC Yes
Receiver Yes
Earphone Jack Yes (Stereo)
SIM Socket Yes (SIM Block Type)
Volume Key Yes
Voice Key Yes
MP3/AAC Yes
MIDI 64 MIDI
I/O Connector 24Pin
Basic Accessory Travel Adaptor

Main LCD：CSTN 128×160 Pixels 65K Color

Sub LCD: CSTN 96×64 Pixels 65K Color

Standard Battery (1000mAh , Li-ion)

Ear-mic

Data Cable

3

3. TECHNICAL BRIEF

3. C3600 TECHNICAL BRIEF

3.1 C3600 Block Diagram

Figure 3-1 C3600 top level block diagram

The Figure 3-1 shows the top level block diagram of C3600, it contains RF and BB part.
The following list is the detailed:

1. AD6527B : ADI digital baseband chipset

2. AD6537B : ADI analog baseband and power supply chipset

3. SI4205 : RF transmitter chipset

4. NEC9993 : NEC MP3 and Midi chipset

5. RD38F4455LLZDQ0 : 256Mb + 256Mb intel Flash memory chipset

6. CL761S : Camera module

7. Others:
A. 24 main key, 3 MP3 play key and 2 side key.
B. 128 x 160 65K CSTN –LCD module
C. Vibrator
D. Mic
E. Speaker and receiver
F. Ear-jack
G. Sim socket
H. Battery connector

4

3. TECHNICAL BRIEF

3.2 RF Part

The RF parts consist of a transmitter part, a receiver part, a frequency synthesizer part, a
voltage supply part, and a VCTCXO part. The Aero transceiver is one chip solution which
supports dual and triple-band GSM/GPRS wireless communications. This device
integrated a receiver based on a low IF(100KHz) architecture and a transmitter based on
a modulation loop architecture which contains a complete dual band transceiver with built
in VCOs. The transceiver employed a 3 wire serial interface to allow an external system
controller to write the control registers for dividers, receive path gain, power down setting,
and other controls.

Figure 3-2 Receiver Block Diagram

Figure 3-3 Frequency Synthesizer Block Diagram

Figure3-4 Transmitter Block Diagram

5

3. TECHNICAL BRIEF

3.3 BaseBand Transmit Section

i. The AD6537B transmit section is designed to support GMSK for both single slot and

multislot applications.

ii. The AD6537B transmit section consists of a digital GMSK modulator, a matched pair of

10-bit DACs and a matched pair of reconstruction filter.

Figure 3-5 AD6537B BASEBAND TRANSMIT SECTION

3.4 BaseBand Receive Section

i. This section consists of two identical ADC channels that process baseband in-phase(I)

and quadrature(Q) signals.

ii. Each channel consists a coarse switched capacitor Anti-alias filter, followed by a low

pass digital filter.

Figure 3-6 AD6537B BASEBAND RECEIVER SECTION

6

4. C3600 TROUBLE SHOOTING

4.1 RF Components

4. TROUBLE SHOOTING

Figure 4-1 RF Components

Reference Description Reference Description

SW500 Mobile S/W U501 PAM

FL401 EGSM SAW Filter FL500 ANT S/W
FL402 DCS SAW Filter U503 LDO

U502 RF Main Chipset
X500 XCTCXO

Table 4-1

ANT500
ANT501

ANT Feedback

Point

7

4. TROUBLE SHOOTING

4.2 RX Trouble

62CH, 7 Level Setting( TCH0

62CH, -6 0 d B m S e ttin g ( BCCH)

START

H P8922:T est M ode

1 C heck A N T

Feed back Pints

2 C heck R egulator

Circuit

R edownload SW ,Cal

3 C heckV C TC X O

Circuit

4 C heck A N T S W

& M o b ile S W

6 C heck R eceiving

IQ

5 C heck SA W

F ilte r C irc u it

4.2.1 Check ANT Feedback Points

See Figure 4-1. Check ANT500 and ANT501 Check Wether the ANT Good Contacting

4.2.2 Check Regulator Circuit

Figure 4-2 Regulator Circuit

Check PIN5

Check PIN 1

RF 2.8V O K ?

YE S

Regulator Circuit OK see

Next Page

Check VCTCXO

NO

PIN6 HIGH ?

YES

Replace the

U503

NO

Change the

Board

8

4. TROUBLE SHOOTING

RF 2. 85V

5

4 3

C536

4.7u

(1608)

C535
22n

4.2.3 Check VCTCXO Circuit

U503

OUT

GND

BYP EN

MIC5255-2.85BM5

VBAT

RF_LDO

1

IN

2

CLKON

C529

4.7n

Figure 4-3 VCTCXO Circuit

Chec Pin3
Figure 4-3

Check Pin 4

Figure 4-3

13Mhz Right?

Y

2.75v Right?

Y

Check U101

N

N

VCTCXO Circuit

no probl em, che ck

below, or software

Replace X501

2V75_VVCXO

X500

C528

100p

R510

100

C539

2.2u

3

OUT

4

VCC

VCONT

26MHz

GND

1

2

R515

C540

0.1u

10K

AFC

9

4. TROUBLE SHOOTING

4.2.4 Check Antenna Switch & Mobile Switch

Tx Test Only

（GSM：PL=7，DCS

：PL=2）

Figure 4-4 Antenna Switch & Mobile Switch

Change Main

Board

N

VC1:L
VC2:L

Check C531，C537,
Whether phone in Rx
state , Figure 4 -4

Check Pin 4，3，5

PAM control Signal

NN

Y

Pin5:-29.5dBm
Pin3:-26.5dBm

Check FL501 pin
10(For GSM)&Pin1(For
DCS) Power Level

Replace SW500

YY

Start

Check SW500 RF cable

Connection

Replace
SW500

Shorten?

N

Y

End

Table 4-2

10

4.2.5 Check SAW Filter

4. TROUBLE SHOOTING

Figure 4-5

When do these two
test, standalone mode
should be applied

Check the SAW filter
Iutput

For GSM：FL401.3
For DCS：FL402.3

Check the SAW filter
Output
For GSM：FL401.3

For DCS：FL402.3

C510

27p

1

1

FL401.1:

~-61dBm

Yes

FL401.3:~-64dBm
FL402.3:~-64dBm

Yes

C513

FL501

3

2

1

IN

G1O

EFCH942MTCA7

2

G2O

5

4

FL502

3

2

1

G1O

IN

2

G2O

EFCH1842TCA7

5

4

C518

C521

C522

1p

L501

27nH

1p

1p

L503

6.8nH

1p

Check the
soldering Is
Ok?

C510（for GSM）

No

Check the soldering
Is Ok?
For GSM：L501,C513
For DCS：L503,C52

No

Change C510 (For

GSM)

The SAW

soldering Is

Ok？

No

Yes

Change
FL401(GSM)
FL402(DCS)

SAW filer is OK, Refer
next page for IQ

signal checking

11

Change
For GSM：L501,C513
For DCS：L503,C521

4. TROUBLE SHOOTING

4.2.6 Checking Receive IQ

check C519，C526
check if there is any
major difference
Refer to Figure4-6

Figure 4-6

Sililar?

No

Replace U102

Yes

Redownload software
Recalibrat

e

Figure 4-7

12

4.3 TX Trouble

Set 62CH，-60dBm level（BCCH）

4. TROUBLE SHOOTING

Start

HP8922 :Test Mode

Set 62CH，7 leve l（TCH0

1、check LDO

2、check VCTCXO

3、check antenna

communication S/W

4.3.1 Check LDO Circuit

Detail on 4.2.1

circuit

circuit

and mobile

Download S/W and calibration

again.

3、check antenna

and mobile

communication S/W

5、check RAM

control signal

4.3.2 Check VCTCXO Circuit

Detail on 4.2.2

4.3.3 Check Transmit IQ

Detail on 4.2.6

13

4. TROUBLE SHOOTING

4.3.4 Check PAM Control Signal

VBAT

Figure 4-8

15

12

17

C520
39P

C581
12p

8

3

1

1

2

2

9

D

D

N

N

G

RSVD

G

P

GSM_OUT

DCS_OCS_OUT

E
S

C

N
E

P

S

A

V

V

9

2
2

1

R509
1k

C504

0.01u

6

4
1

1

6

8

7

D

D

D

N

N

N

G

G

G

U502

SKY77325

T
T
A
B

0
2

3
1

D
N
G

C503

0.01u

5

C505
18p

0

1

9

1

1

3

4

D

D

N

N

G

G

A
1

C
C
V

NCV

3

8

1

7

1

2

D

D

N

N

G

G

PAC_ENABLE

DCS_PCS_IN

B

1
C
C
V

C506

0.01u

C502
33p

GSM_IN

C507
22u

R501 100

C501

4

BS

2

6

5

TX_RAMP

27p

R502 100

C509
27p

PA_BAND

PA_EN

GPIO_17

GPIO_16

Check TX-RAMP and
PA-EN
Check the
difference
*Reference Graph
4-8

Almost the

same?

Yes

No

Download S/W
again

Transmit IQ signal OK，
Check RF transmit level

reference on next page.

14

4. TROUBLE SHOOTING

Figure 4-9

4.3.5 Check Antenna Switch and Mobile Switch

Please refer to 4.2.4

4.4 Power On Trouble

Figure 4-10

15