LG KG110 - Fun & Tools

37
4. TROUBLE SHOOTING
4.3.1 Check Crystal Circuit
VCC_ REF
17
VAFC_NC
18
REFI NB
19
REFI N
20
REF_OP
21
QB
22
Q
23
VCC_ BBQ
24
RX1900B
25
RX1900
26
RX1800B
27
RX1800
28
RX900B
29
RX900
30
RX850B
31
RX850
32
GND
33
VCC_ F E
1
I
2
VCC_BBI
4
IB
3
SDATA
5
SCLK
6
SEN
7
NC
8
VLDO3
9
TXOP_LO
10
TXOP_HI
11
VCC_TXVCO
12
VDD
13
VBAT
14
VLDO1
15
VLDO2
16
AD6548
C437 1000p
AFC
C438
47p
1
R420 1K
4
L409
680nH
26MHZ
3 2
C439
0.1u
DSX321SL2
Y400
X
Graph 4-5
Figure 4-10
26MHz ok?
VCTCXO Circuit is OK
See next Page to Check
ANT SW & Mobile SW
Change Y400
YES
NO
26MHz si
g
nal
Graph 4-6
Cr
y
stal
p
in1