LG KE520 Service Manual page 50

4.1.2.4 RF Transceiver (B6PLD)
Digital Interface to Baseband. Integrate LNA and VCO circuit.
C408
22p
A1
PCSLNAI
B1
PCSLNAIB
C2
PCSDCSGND
C1
DCSLNAI
D1
DCSLNAIB
D2
DCSG90GND
E1
G90LNAI
F1
G90LNAIB
E2
G90G85GND
G1
G85LNAI
H1
G85LNAIB
F2
G85GND
G2
GNDLNA_TX1
H2
TXON
E3
GNDDMIXIN
J2
DMIXIN
J1
DMIXINB
C426
22p
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
U401
C402
3.9p
C404
3.9p
C407
C406
68p
33nF
C405
0.1u
XON
GNDVCXO_OR
VOUTEF2
VCCVCXO
VOUTEF1
VCCLOGIC2
U401
GNDLOGIC
CLOGIC1
R2A60167BG
VCCLOGIC1
STROBE
SYSCLK
RXTXDATA
RXTXEN
TEST1
CTRLEN
CTRLDATA
CTRLCLK
C424 0.01u
<Fig.4> RF Transceiver Circuit Diagram
- 51 -
4. TROUBLE SHOOTING
L402
8.2nH
B9
C8
D7
0.1u
C9 C416
D8
SLICER_IN
D9
E7
0.01u C420 0.01u
C419
F7
E9
E8
F8
F9
DIGITALRF_DATA
G7
DIGITALRF_ENABLE
G6
G9
DIGITALRF_RF_CS
G8
DIGITALRF_RF_DATA
H9
DIGITALRF_RF_CLK
SYSCLKEN
C_VCCRF
VRIO
C409
0.01u
U400
1 VCC
_OE
5
2 A
3
4
Y
GND
SN74LVC1G125DRLR
VCC_SYN
VRIO
LGE Internal Use Only