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4-3
Block Diagrams
4-2-1 RF Transmit Part
a
b
c
d
e
U305
HD155128TF
Antenna
S/W
U304
U108
VP40575
TXEN
RAMPD
A
C
BAND Selection
- GSM :
Lo
w
- DCS :
High
ITXP
ITXN
QTXP
QTXN
Loop
Filter
TX VCO
U200
Dual P
A
M
U312
APC Circuit
Coupler
15
3
1
3
7
5
U318
U318
8
8
13
7
2
540 MHz
PCN :
1575 ~ 1650 MHz (Tx)
GSM :
1150 ~ 1185 MHz
41
4
1
1
1
2
3
4
5
38
35
20
19
18
17
30
47
10
6
8
1
4
2
5
2
1
Ant.
S/W
Control
Circuit
3VTX
TXEN2
VC1
VC2
VC3
VC3
VC2
VC1
GSM(Tx)
DCS(Tx)
Rx
H
H
H
L
L
L
L
LL
11
SI4133-MLP28
U302
VCTCXO
13MHz
U303
IF VCO
1080MHz
PLL1
PLL2
RF VCO
AFCD
A
C
10
23
15
880 ~ 915MHz(EGSM)
890 ~ 915MHz(PGSM)
1710 ~ 1785MHz(DCS)
U305
HD155128TF
Antenna
S/W
U304
U108
VP40575
TXEN
RAMPD
A
C
BAND Selection
- GSM :
Lo
w
- DCS :
High
ITXP
ITXN
QTXP
QTXN
Loop
Filter
TX VCO
OSC301
Dual P
A
M
U312
APC Circuit
880
~
915
MHz
1710
~
1785
MHz
Coupler
15
9
1
3
7
5
U318
8
13
7
2
1080 MHz
DCS :
1575 ~ 1650 MHz (Tx)
E-GSM :
1150 ~ 1185 MHz
41
4
1
1
1
2
3
4
5
38
35
20
19
18
17
30
47
5
1
8
1
4
2
5
2
Ant.
S/W
Control
Circuit
3VTX
TXEN2
VC1
VC2
VC3
VC3
VC2
VC1
E-GSM(Tx)
DCS(Tx)
Rx
H
H
H
L
L
L
L
LL
11
SI4133-MLP28
U302
VCTCXO
13MHz
U303
IF VCO
1080MHz
PLL1
PLL2
RF VCO
AFCD
A
C
10
23
15
E-GSM
DCS
Summary of Contents for SGH-N300
Page 2: ...Samsung Electronics Co Ltd Printed in Korea 06 2001 Rev 1 0 GH68 02097A ELECTRONICS ...
Page 11: ...Exploded Views and Parts List 1 8 1 10 Desk Top Charger DESK TOP CHARGER GH44 00206A ...
Page 12: ...2 1 PCB Diagrams Schematic Diagrams 2 PCB Diagrams 2 1 Main Top ...
Page 13: ...2 2 PCB Diagrams Schematic Diagrams 2 2 Main Bottom ...
Page 41: ...Flow Chart of Troubleshooting 5 12 J101 SPK101 U110 PWO1P PWO1N SPK SPK 6 2 3 SPK SPK ...