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4-3
Block Diagrams
4-2-1 RF Transmit Part
VCTCXO
(U102)
EGSM TX
880 ~ 915 MHz
(CH62 :
902.4 MHz)
DCS TX
1710 ~ 1785 MHz
(CH698 :
1747.4 MHz)
Antenna
S/W
(U107)
RF
Conector
(CN1)
VP40578
(U406)
S
D
ATA
SCLK
SENB
PDNB
PD
LPF
Si4200 (U104)
I
Q
Dual P
A
M
(U106)
RF
PLL
Si4133-T (U103)
AFC
+VBA
TT
Txpo
w
e
r
from U406
2.8VRFVCC
8
2.8VTX
TXEN2
from U406
VC1
VC2
Ant.
S/W
Control
Circuit
BAND Selection
VREG
BAND Selection
- GSM :
Lo
w
- DCS :
High
<EGSM>
1279 ~ 1314 MHz
<DCS>
1327 ~ 1402 MHz
-6dBm
@ 1301.4 MHz (G)
-9dBm
@ 1364.4 MHz (D)
21
1
53
9
11
7
1
24
25
5
6
7
8
31
1
3
7
26,27
23,24
12,13
9,10
IF
PLL
9
/2
<EGSM>
880~895 MHz :
798 MHz
895~900 MHz :
790 MHz
900~915 MHz :
798 MHz
<DCS>
766 MHz
-6dBm
@ 798 MHz
-9dBm
@ 766 MHz
1
2
3
VC2
VC1
Tx(GSM)
Tx(DCS)
Rx
L
L
H
H
LL
TXEN2
Txpo
w
e
r
2
1
Summary of Contents for SGH-T408
Page 2: ...Samsung Electronics Co Ltd Printed in Korea 01 2003 Rev 1 0 GH68 03159A ELECTRONICS ...
Page 11: ...2 1 PCB Diagrams 2 PCB Diagrams 2 1 Main Top ...
Page 12: ...2 2 PCB Diagrams 2 2 Main Bottom ...
Page 22: ...4 Block Diagrams 4 1 Main Baseband 4 1 Block Diagrams ...
Page 38: ...5 13 5 8 Receiver Part Flow Chart of Troubleshooting and Circuit Diagrams ...
Page 39: ...5 14 Flow Chart of Troubleshooting and Circuit Diagrams ...
Page 43: ...5 18 Flow Chart of Troubleshooting and Circuit Diagrams 5 12 GSM Receiver ...
Page 44: ...Flow Chart of Troubleshooting and Circuit Diagrams 5 19 5 13 GSM Transmitter ...
Page 45: ...5 20 Flow Chart of Troubleshooting and Circuit Diagrams 5 14 DCS Receiver ...
Page 46: ...Flow Chart of Troubleshooting and Circuit Diagrams 5 21 5 15 DCS Transmitter ...