Samsung SGH-C120 User manual

GSM TELEPHONE
SGH-C120
GSM TELEPHONE CONTENTS
1. Specification
2. Flow Chart of Troubleshooting
3. Exploded Views and Parts List
4. Electrical Parts List
5. PCB Diagrams
6. Block Diagrams

Samsung Electronics Co.,Ltd.
Code No.: GH68-08501A
2005. 11. Rev.1.0
ⓒ
This Service Manual is a property of Samsung Electronics Co.,Ltd.
Any unauthorized use of Manual can be punished under applicable
International and/or domestic law.

SAMSUNG Proprietary-Contents may change without notice
1. SGH-C120 Specification
1-1
This Document can not be used without Samsung's authorization
1-1. GSM General Specification
GSM900
Phase 1
EGSM 900
Phase 2
DCS1800
Phase 1
Freq. Band[MHz]
Uplink/Downlink
890~915
935~960
880~915
925~960
1710~1785
1805~1880
ARFCN range 1~124 0~124 &
975~1023 512~885
Tx/Rx spacing 45MHz 45MHz 95MHz
Mod. Bit rate/
Bit Period
270.833kbps
3.692us
270.833kbps
3.692us
270.833kbps
3.692us
Time Slot
Period/Frame
Period
576.9us
4.615ms
576.9us
4.615ms
576.9us
4.615ms
Modulation 0.3GMSK 0.3GMSK 0.3GMSK
MS Power 33dBm~13dBm 33dBm~5dBm 30dBm~0dBm
Power Class 5pcl ~ 15pcl 5pcl ~ 19pcl 0pcl ~ 15pcl
Sensitivity -102dBm -102dBm -100dBm
TDMA Mux 8 8 8
Cell Radius 35Km 35Km 2Km

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Specification
1-2
This Document can not be used without Samsung's authorization
1-2. GSM TX power class
TX Power
control level GSM900
533±2dBm
631±2dBm
729±2dBm
827±2dBm
925±2dBm
10 23±2dBm
11 21±2dBm
12 19±2dBm
13 17±2dBm
14 15±2dBm
15 13±2dBm
16 11±3dBm
17 9± 3dBm
18 7±3dBm
19 5±3dBm
TX Power
control level DCS1800
030±3dBm
128±3dBm
226±3dBm
324±3dBm
422±3dBm
520±3dBm
618±3dBm
716±3dBm
814±3dBm
912±4dBm
10 10±4dBm
11 8±4dBm
12 6±4dBm
13 4±4dBm
14 2±5dBm
15 0±5dBm

SAMSUNG Proprietary-Contents may change without notice
2. SGH-C120 Flow Chart of Troubleshooting
2-1
This Document can not be used without Samsung's authorization
2-1.Baseband
2-1-1. Power ON
'Power On' does not work
Voltage >=3.3V
Download again
Charge the Battery
Pin#J12 >= 2.8V Check U300 and C315
Pin#A13 and
pin#A14 =2.8V Check U300 and C316
Freq = 13MHz
Vrms >=300mV
Vpp≒900mV
Check the clock generation circuit
(related to OSC100)
Check the initial operation
END
No
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
pin#G11 =
1.8V
No
Yes
Check the current consumption
Check the Vbat Voltage
Check the pin of U300
Checktheclocksignalatpin#8ofU100
Current consumption
>= 100mA
①
②
③
④

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-2
This Document can not be used without Samsung's authorization
①
①
②
③
②
④

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-3
This Document can not be used without Samsung's authorization
VCCB_2.9V
R302
C316
VCCA_2.9V
R303
NEG
POS
C325
BAT300
TR300
C313
R311
C317
VBAT
VCCD_2.9V
R307
VRF_2.9V
C311
C306
VCCA_2.9V
C304
C302
C301
C312C315
R300
C324
VRF_2.9V
C308
C300
R301
VRTC_2.9V
VRTC_2.9V
C322
SIM300
VCC_1.8A
C305
C318
C309
R304
QANEOX
1D
C307
C12
VREFA10
NGERV
41R
PGERV
31M
VRTCH11
VSIMK12
5G
1SSV
4K
2SSV
3SSV 2R
4SSV 6P
MCVXV
31R
VL4S_AA12
VL4S_BB11
VL5S_AD10
C9
VL5S_B
VLDO_1G11
VLDO_2J12
A13
VLDO_3
VLDO_4B12
VLDO_5B10
VLDO_6A14
VLDO_7
3DDV 6N
VDD34C11
5DDV 01C
76DDV 31B
BDDV 6A
DDDV 11N
VDDV 11L
1OI_DDV 5N
4J
2OI_DDV
4C
LTCO_DDV
VEXTE14
SIM_RSTK11
PXT
7E
UP_CLKN9
UP_IOP10
UP_RSTR10
VACCF14
VBATE13
1DDV 3J
VDD12J13
2DDV 3M
NQXTXR
6C
PQXTXR
7C
SCLK_PSCL8
M7
SDI_PSC
SDO_PSCN7
SERCK
C2
SERDA
C1
B1SERLE1
SERLE2
A2
SIM_CLKK14
SIM_IOJ11
1FERAR
6B
2FERAR
5B
R3RESETN_CSP
O_TESER
9K
RTC_ALMNH10
KLC_CTR
4N
RWN
L2
NIXTXR
6D
PIXTXR
7D
C5OCTL1
OCTL2
F5
OCTL4
A4
G6OCTL5
OCTL6
B3
A3OCTL7
FUB_1WSP
7L
PEEK_RWP
9M
N1WS_RWP
51C
2WS_RWP
41C
NTUOCIM
51P
PTUOCIM
51N
1
5CN
6CN 2
7CN
5P
11F
LTCO_DNG 4B
1CSP_DNG 51B
2CSP_DNG 51K
QRTNI
01L
L3I|O
LED1_DRVG13
LED2_DRVG12
6R CM
NNICIM
41M
PNICIM
41N
71SDNG 01K
2SDNG 8F
3SDNG 9F
4SDNG 01F
5SDNG 7G
6SDNG 8G
7SDNG 9G
01G
8SDNG
9SDNG 6H
VDNG 31P
RUCH_
DNG
6F
BDNG
DDNG 01M
QDNG 8E
7F
1SDNG
01SDNG 7H
11SDNG 8H
9H
21SDNG
7J
31SDNG
41SDNG 8J
51SDNG 9J
61SDNG 01J
D3
DB15
D2
DB2
K3
J5DB3
DB4
J6
DB5
H5
G3DB6
DB7
G4
DB8
F4
DB9
F1
RTNID
3P
K8
KCIAD
4R
6L IDIAD
ODIAD
6M
NRIAD
4P
DB0
K1
DB1
K2
DB10
F2
DB11
F3
DB12
E2
DB13
E3
DB14
21P NBTUOA
21R PBTUOA
41L NNIXUA
PNIXUA
51M
31L NTUOXUA
PTUOXUA
31K
CH_BDRVE11
CH_ISENF12
CH_RESD14
E9
CREF
CSN_PSC
L5
N1AB3
AB4
N2
AB5
M2
M1AB6
AB7
K7
AB8
K5
ADC_AUX1E10
CFA
9D
NATUOA
21N
PATUOA
11P
U300
AB0
K6
P1AB1
AB2
C314
VCCD_2.9V
VBAT
C303
INTRQ
PWR_KEEP
MOTOR
RING_EN
KEY_COL(2)
KEY_ROW(0)
TSR
BUZZER
SIMCLK
SIMDATA
SIMRST
GSM_TX_EN
DCS_TX_EN
VREF
NTUOCIM
PTUOCIM
NO_RWP
NO_GIJ
RTCALARM
K23KLC
RTX_IN
RTX_IP
RTX_QN
RTX_QP
UP_SCLK
UP_SDI
UP_SDO
TXPOWER
PATUOA
NBTUOA
PBTUOA
NNIXUA
PNIXUA
NTUOXUA
PTUOXUA
UP_CS
TNI_PSD
KEY_BL1
CM_M31KLC
NNICIM
PNICIM
RF_EN
XOENA
FLASH_RESET
DSP_IO
DSP_RWN
AFC
NATUOA
DSP_DB(13)
DSP_DB(12)
DSP_DB(11)
DSP_DB(10)
DSP_DB(1)
DSP_DB(0)
DSP_AB(8)
DSP_AB(7)
DSP_AB(6)
DSP_AB(5)
DSP_AB(4)
DSP_AB(3)
DSP_AB(2)
DSP_AB(1)
DSP_AB(0)
DSP_DB(0:15)
DSP_AB(0:8)
SERLE
SERDAT
SERCLK
TX_EN
TX_BAND_SEL
DSP_DB(9)
DSP_DB(8)
DSP_DB(7)
DSP_DB(6)
DSP_DB(5)
DSP_DB(4)
DSP_DB(3)
DSP_DB(2)
DSP_DB(15)
DSP_DB(14)

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-4
This Document can not be used without Samsung's authorization
R106
R104
R105
VRF_2.9V
VCCD_2.9V
R107
R110
1
L
A
T
X
30
2
L
A
T
X
9
N
D
P
_
10
T
E
S
E
R
_
_SEN
2
13
D
D
V
28
D
D
V
29
11
O
I
V
26
V
I
D
X
32
N
E
X
E
D
O
M
X
25
8XOUT
31
21
18
RFIPN
RFIPP
17
16
H
O
F
R
15
L
O
F
R
SCLK
1
SDIO
3
D
D
V
12
D
D
V
33
34
C
N
C
N
35
RFIAN 24
RFIAP 23
20
RFIDN
RFIDP
19
RFIEN
22
RFIEP
27
C
F
A
BIN
6
7
BIP
BQN
4
5
BQP
14
D
N
G
D
N
G
U100
OSC100
2
4
3
1
C120
C123
VRF_2.9V
R111
C133
C130
C134
RF_EN
SERDAT
AFC
SERLE
SERCLK
13MHZ_BB
RTX_QP
RTX_QN
RTX_IP
RTX_IN
XOENA

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-5
This Document can not be used without Samsung's authorization
2-1-2. Initial
Initial Failure
The pin #G11 of U101 =
1.8V and
the pin #J12 of U101 =
2.8V ?
Check the U300
(if it has some problem, it is to be replaced.)
Yes
No
Is the pin #K9 of U101
"Low →High" ?
Yes
No Check the U300
(if it has some problem, it is to be replaced.)
There is 32.768kHz wave
forms at the C216 and
C217
Yes
No
Check the U200
Is the pin #A4 of U300
is "High"
The voltage is "High" at
the C313,C315,C316 Check the U300
Check the U100
LCD display is O.K
No
No
Yes
Yes
Yes
Check the LCD part
No
Sound is O.K
Yes
No
Check the Audio part
END
Yes
①
①
②
③
④

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-6
This Document can not be used without Samsung's authorization
①
②
③
④

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-7
This Document can not be used without Samsung's authorization
C218
0
1
NK
L
C
_
0
M
S
X
A
T
A
D
_
0
M
S
X
2
1
U
XTIC_MODE D12
F
E
R
V
X0
1
F
P16 XPA4/OEN
P15 XPA5/WAITN
T15 XPA6/BE1N
M9 XPA7/IRQ1
XPA8/IRQ2
T5
P2 XPA9/IRQ3
5
R1
M
W
P
X
E8
XRTCALARM_N
0
M
I
_
0
3
A
P
X
3
F
1
E1
M
I
_
1
3
A
P
X
4
1
H
N
0
S
C
_
2
3
A
P
X
A
Q
E
R
_
T
_
3
3
A
P
X
7
1
N
7
1
MB
Q
E
R
_
T
_
4
3
A
P
X
3
1
L
2
2
A
_
5
3
A
P
X
N
5
S
C
_
3
2
A
_
6
3
A
P
X5
1
N
N14 XPA3/CS4N
2
M
W
P
/
3
2
A
P
X
6
H
3
M
W
P
/
4
2
A
P
X
5
H
3
M0
M
O
_
5
2
A
P
X
2
G1
M
O
_
6
2
A
P
X
K
L
C
_
1
M
S
_
7
2
A
P
X
4
G
5
G0
M
O
I
_
8
2
A
P
X
1
F1
M
O
I
_
9
2
A
P
X
XPA2/CS3N
M11
0
X
R
/
6
1
A
P
X
3
L
4
E0
Q
R
D
_
7
1
A
P
X
3
1
PK
C
A
_
T
_
8
1
A
P
X
2
LI
S
O
M
_
P
C
/
9
1
A
P
X
XPA1/CS2N
M14
O
S
I
M
_
P
C
/
0
2
A
P
X
1
L
K
C
S
_
P
C
/
1
2
A
P
X
4
K
6
JN
S
S
/
2
2
A
P
X
XOSC32OUT C6
M15 XPA0/CS1N
XPA10/IRQ4
N2
5
KX
R
A
D
R
I
/
1
1
A
P
X
X
T
A
D
R
I
/
2
1
A
P
X
1
N
6
G1
X
T
_
3
1
A
P
X
1
X
R
_
4
1
A
P
X
3
G
4
H0
X
T
/
5
1
A
P
X
4
T3
T
U
O
S
/
8
B
K
_
P
C
X
4
T
U
O
S
/
9
B
K
_
P
C
X
3
N
K
C
T
_
P
C
X
7
D
3
1
DO
D
T
_
P
C
X
8
GS
M
T
_
P
C
X
N
T
S
R
T
_
P
C
X
9
F
XCP_WEN
C13
B
T
S
R
F
X
4
F
4
L0
N
I
S
/
0
B
K
_
P
C
X
1
N
I
S
/
1
B
K
_
P
C
X
5
L
4
M2
N
I
S
/
2
B
K
_
P
C
X
1
T3
N
I
S
/
3
B
K
_
P
C
X
4
N
I
S
/
4
B
K
_
P
C
X
2
R
3
T0
T
U
O
S
/
5
B
K
_
P
C
X
1
T
U
O
S
/
6
B
K
_
P
C
X
3
U
3
P2
T
U
O
S
/
7
B
K
_
P
C
X
F7 XCP_D3
XCP_D4
C5
D6 XCP_D5
E7 XCP_D6
XCP_D7
D5
XCP_D8
C4
B4 XCP_D9
I
D
T
_
P
C
X
7
C
XCP_D1
B5
B3 XCP_D10
XCP_D11
C1
C2 XCP_D12
XCP_D13
D2
XCP_D14
D3
E3 XCP_D15
XCP_D2
F8
C14 XCP_A5
XCP_A6
A16
A15 XCP_A7
B17 XCP_A8
XCP_A9
C17
XCP_CSRAMEN
A13
A12 XCP_CSROMEN
A6 XCP_D0
K13 XCP_A17
XCP_A18
K14
L14 XCP_A19
E14 XCP_A2
L15 XCP_A20
XCP_A21
L16
XCP_A3
D15
XCP_A4
B15
XCP_A1
F11
XCP_A10
D16
F14 XCP_A11
G14 XCP_A12
XCP_A13
G13
G17 XCP_A14
XCP_A15
J12
XCP_A16
K12
X2RTC D10
XAG0 B11
A11
XAG1
E11
XAG2
XAG3 D11
B7
XBSWN
M12
XCPTSTSTOP_CKO
XCP_A0_BEON
B13
S
S
V0
1
G
7
H
S
S
V
1
1
H
S
S
V
7
J
S
S
V
S
S
V6
K
A
S
S
V0
1
E
L
L
P
D
_
S
S
V5
1
E
A7
X1RTC
S
S
V0
1
L
7
M
S
S
V
S
S
V8
L
1
1
J
S
S
V
9
L
S
S
V
S
S
V3
A
S
S
V6
F
9
G
S
S
V
E
D
D
V6
1
N
6
1
E
E
D
D
V
E
D
D
V7
1
E
6
1
G
L
L
P
D
_
D
D
V
8
D
C
T
R
V
2
A
S
S
V
7
K
S
S
V
6
L
S
S
V
1
1
C
A
D
D
V
E
D
D
V1
B
4
1
B
E
D
D
V
1
M
E
D
D
V
E
D
D
V2
U
8
P
E
D
D
V
E
D
D
V5
1
U
6
1
U
E
D
D
V
D
D
V1
G
1
R
D
D
V
D
D
V4
R
3
1
T
D
D
V
D
D
V6
1
R
7
1
R
D
D
V
D
D
V5
A
6
1
C
D
D
V
U5
RWN
H13
TCK
H12
TDI
F12
TDO
TMS G12
F15
TRST
2
E
D
D
V
D
D
V7
1
L
N7
DB#9
INT#0 N4
IO7 R12
IOBIT#1 K11
L12
IOBIT#2
1
C
N
C
N2
2
1
C
B
T
S
R
P10
DB#15
DB#2 R6
P6
DB#3
DB#4 U7
DB#5 T7
R7
DB#6
DB#7 M6
DB#8 P7
CKO G15
P5
DB#0
DB#1 U6
DB#10 N8
DB#11 M8
U11
DB#12
DB#13 T11
DB#14 R11
AB#2 R13
AB#3 N11
P11
AB#4
AB#5 P12
R14
AB#6
T14
AB#7
AB#8 T17
I
K
C7
1
F
U200
AB#0 U13
M10
AB#1
C215
C221C220
VCC_1.8A
VCC_1.8A
C217
R205
VCC_1.8A
R209
R210
C206
C222
C207
R200
VCCB_2.9V
R203
R219
R208
OSC200
23
41
C205
R206
R212
VBAT
R213
100K
VRTC_2.9V
C219
DSP_TCK
R204
VCCD_2.9V
VCCD_2.9V
C208
TH200
DSP_TDI
VCCD_2.9V
DSP_TMS
0
2
2
R
R214
R202
DSP_TDO
C216
RING_EN
LED_EN
LED_EN
VIB_EN
CP_TCK
TR_RST
BAT_CF
DSP_AB(0)
CHG_ON
DLC_DETECT
A(0:20)
CP_TDI
CP_TMS
DSP_DB(14)
DSP_DB(13)
DSP_DB(12)
DSP_DB(11)
DSP_DB(10)
DSP_DB(1)
DSP_DB(0)
CLK13M_TR
DSP_AB(8)
DSP_AB(7)
DSP_AB(6)
DSP_AB(5)
DSP_AB(4)
DSP_AB(3)
DSP_AB(2)
DSP_AB(1)
DSP_RWN
TR_RST
DSP_IO
DSP_INT
DSP_DB(9)
DSP_DB(8)
DSP_DB(7)
DSP_DB(6)
DSP_DB(5)
DSP_DB(4)
DSP_DB(3)
DSP_DB(2)
DSP_DB(15)
A(20)
A(2)
A(19)
A(18)
A(17)
A(16)
A(15)
A(14)
A(13)
A(12)
A(11)
A(10)
A(1)
A(0)
TR_RST
ICHRG
D(14)
D(13)
D(12)
D(11)
D(10)
D(1)
D(0)
CP_CSROMEN
CP_CSRAMEN
A(9)
A(8)
A(7)
A(6)
A(5)
A(4)
A(3)
A(21)
KEY_ROW(0)
KEY_COL(4)
KEY_COL(3)
KEY_COL(2)
KEY_COL(1)
KEY_COL(0)
D(9)
D(8)
D(7)
D(6)
D(5)
D(4)
D(3)
D(2)
D(15)
UP_SDO
LCD_CS
UP_SDI
JACK_IN
DEBUG_RXD
DEBUG_TXD
SDS_RXD
SDS_TXD
CLK32K
FLASH_RESET
CP_WEN
TR_RST
CP_TDO
KEY_ROW(4)
KEY_ROW(3)
KEY_ROW(2)
KEY_ROW(1)
DEBUG_DCD
CP_OEN
A(22)
DEBUG_DSR
EAR_SWITCH
DEBUG_RTS
DEBUG_DTR
CHG_DET
DEBUG_CTS
PWR_KEEP
SIMRST
DEBUG_RI
UP_CS
UP_SCLK
DSP_DB(15:0)
D(0:15)
KEY_ROW(0:4)
KEY_COL(0:4)
DSP_AB(8:0)
VREF
SIMDATA
SIMCLK
RTCALARM
INTRQ
UPPER_BYTE

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-8
This Document can not be used without Samsung's authorization
2-1-3. Sim Part
Check the voltage at
pin#1 of SIM300 >=
2.8V ?
"Insert SIM is displayed on the LCD
Check the SIM
connector's (SIM300)
connection to SIM card
Check the U300
Resolder or change SIM300
END
No
Yes
Yes
Yes
Yes
No
No
Is there any signals
pin#2,#3,#4 of SIM300 ? Check the U200 & U300
Check the SIM Card
①
③
②

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-9
This Document can not be used without Samsung's authorization
③
③
①
②

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-10
This Document can not be used without Samsung's authorization
2-1-4. Microphone Part
Is the assembled status
of microphone O.K?
Microphone does not work
Reassembled the microphone
Resolder or change
R400,R401,R402,R403,R404,R405
R407,R410,R413,R414,L400,L401
C403,C407,C413
END
No
Yes
Yes
Yes
Yes
No
Is microphone ok?
No
Check U300
Check the reference voltage on mic path
VR401 ≒2.0V ?
Yes
①
②

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-11
This Document can not be used without Samsung's authorization
②
①

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-12
This Document can not be used without Samsung's authorization
2-1-5. Receiver Part
2-1-6. Buzzer Part
There is no sound from the Receiver
Is the terminal of Receiver
O.K ?
No
Replace the Receiver
Yes
No
Yes
Check U300,R423,R424
Is there any signals at
the pin#A11 and
pin#N12 of U300 ?
END
①
②
There is no sound from the Buzzer
Is the terminal of Buzzer
O.K ? Replace the Buzzer
Is there any signals at
the pin#A13 and
pin#N12 of U300 ? Check U300,D200,R218
END
Yes
Yes
Yes
Yes
No
No

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-13
This Document can not be used without Samsung's authorization
①
①
②
②

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-14
This Document can not be used without Samsung's authorization
D200
R218
C227
VBAT
BUZ200
C310
BUZZER
R423
VR404
TA401
23
1
TR400
R412
R424
C417
C413
L400
R410
VR405
R403
C410
2
3
4
5
6
EAR400
1
R407
C407
VR403
R413
R414
TA400
R420
R409
VR402VR401
CN400
C401
R417
C405
VR410
R419
C419
C403
C415
R401
C418
C400
VCCA_2.9V
C416
123
4
5
6
78
R405
ZD401
R415
R421
R406
TA402
C408
R404
C406
R422
C409
C404
R411
MIC400
VCCA_2.9V
R418
VCCD_2.9V
R408
C402
R416
VOUT3
VBAT
R425
U400
6CE
GND2
GND
5
4NC
1
VDD
VBAT
C420
R426
C424
C426
3
1
2
R427
D400
C423
C421C422
L401
R400
R402
MOTOR
VIB_EN
VR411
AOUTAP
AUXINP
JACK_IN
MOT+
AOUTBN
AUXOUTN
AUXINN
EAR_SWITCH
MIC+
AOUTAN
MIC
MICINP
MICINN
MICOUTN
MICOUTP
AUXOUTP
AOUTBP

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-15
This Document can not be used without Samsung's authorization
F101 CHECK
pin8 ≥-65dBm ?
2-2.RF
2-2-1. EGSM RX
CONTINUOUS RX ON
RF INPUT : 62CH
AMP : -50dBm
NORMAL CONDITION
catch the channel? CHECK
ANT contact ?
U100
pin 12,13,25,26,27:
2.8V ?
F101 CHECK
pin10 ≥-65dBm ?
U100 CHECK
pin21,22 ≥-65dBm ?
F101,RFS100
resolder or change
F101
resolder or change
C127,C129,L107
resolder or change
U300 pinA13, C314
change or resolder
U100 CHECK
pin 30,31 :
26MHz ?
Vp-p : 950mV?
OSC100
change or resolder
U100
resolder or change
U300 CHECK!!
U100
pin 4,5,6,7 Vp-p
: 120mV ?
NO
YES
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
①
③
②
④⑤
⑥
⑦
⑧
F100 CHECK
pin6,7 ≥-65dBm ?
F100
resolder or change
YES
NO

SAMSUNG Proprietary-Contents may change without notice
SGH-C120 Flow Chart of Troubleshooting
2-16
This Document can not be used without Samsung's authorization
②
③
③
④
⑤
⑥
⑥
⑦
⑧