![background image](http://html.mh-extra.com/html/samsung/sgh-r225/sgh-r225_service-manual_1191008026.webp)
SGH-R225 Block Diagrams
4-3
4-2-1 RF Transmit Part
햲
햳
햴
햵
햶
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)
HD155128TF
U454
Antenna
S/W
U203
VP40553-2
U618
TXEN1
RAMPDAC
BAND Selection
- GSM : Low
- DCS : High
ITXP
ITXN
QTXP
QTXN
Loop
Filter
TX VCO
U200
Dual P
A
M
U476
TXEN1
BAND Selection
RAMPDAC
17
18
19
20
38
35
30
47
23
11
15
3
7
10
6
8
1
5
4
4
3
2
5
3
1080 MHz
3VTX
TXEN2
4,9
5
8
VC1
VC2
21
1
8
RF
Conector
(CN1)
10
1080 MHz
VCTCXO
(13MHz)
(U100)
PLL1
PLL2
SI4133-XM2
(U478)
RF VCO
IF VCO
APCIC
(U611)
VC2
VC1
Tx(DCS)
Tx(GSM)
Rx
H
H
L
L
LL
Ant. S/W
Control
Circuit
3
2
PCS
1850 ~ 1910 MHz
(CH661 : 1880 MHz)
EGSM
880 ~ 915 MHz
(CH62 : 902.4 MHz)
34
1
GSM : 1150 ~ 1185 MHz
PCS : 1705 ~ 1765 MHz(Rx)
1715 ~ 1775 MHz(Tx)
1
2
3
4
5
1
Coupler
Coupler
(U623)
(U622)
5