LG -T300 Service Manual page 91

4. TROUBLE SHOOTING
CIRCUIT
U102
AD24
A24
K4
nROM_CS
CS0_N
M3
nRAM_CS
CS1_N
R3
nADV
ADV_N
J6
nWAIT
WAIT_N
P9
ANAMON
T2
MEM_CLK
BFCLK0
K15
FSYS_EN
FSYS_EN
M15
EPN
M16
EPP
R14
HSL
T14
HSR
N16
3.5phi HEADSET
1V8_VDD
JACK_DETECT
HP_ROUT
HP_LOUT
C301
270pF
0
EAR_GND
R326
HOOK_DETECT
LGE Internal Use Only
TP01
TP02
EPN
C143 C140 C142 C141
EPP
DNI DNI 47p 47p
HSR
HSL
EPN
EPP
HSL
HSR
TP04
1V8_VDD
R336
TP03
1M
S
G
Q201
D
R337
100K
R338
10
FB304
DNI
TP04
L301
0.1uH
TP0
L302
0.1uH
R304
C327
270pF
DNI DNI
VAUX
1V8_VDD
R334
100K
R305
OUT IN-
47ohms
4 3
GND
2
VCC IN+
5 1
C326
U303
120pF
VHSMIC
C304
560pF
0.022uF
C312
HS_MIC_N
C306
10pF
C302 0.022uF
HS_MIC_P
C305
560pF
2. TROUBLE SHOOTING
AUDIO AMP SUB SYSTEM & SIGNAL DISTRIBUTOR
VBAT
FB208
120
U20
TP01
OUT+
OUT-
C240 1u
C2
IN1-
C239 1u
C1
IN1+
U203
HPL
C231 1u
D2
IN2- HPR
C230 1u
D1
IN2+
C229 1u
D3
IN3-
C228 1u
C3
IN3+ CPVDD
CPVSS
CP
CN
TP02
C242
I2C_SCL
2.2u
I2C_SDA
C241
2.2u
R223
0
L304
0.1uH
FB302 1800
FB301
1800
FB305
1800
VA304 VA303 VA302 VA305
R307
100
C344
DNI
R301
2.2Kohms
C303
2.2uF
- 92 -
Copyright © 2010 LG Electronics. Inc. All right reserved.
C245 C244
2.2u 0.1u
C5
D5
FB2041800
A2
A1
FB2051800
C236 C235
0.1u 0.1u
B5 C232 2.2u
C237 C238
A3 C233 2.2u
R225 R224 47p 47p
A4
20 20
A5 C234 2.2u
Headset MIC
1V8_VDD
Resoldering points (components)
R233
220
C243
0.1u
EAR_GND
FM_ANT_1
ZD302
C325
EDTY0009401
24p
EAR_GND
M6
2
M1
3
M4F
4
M3
5
M4
6
M5
1
J301
Only for training and service purposes
RCV_SPK_P
RCV_SPK_N
HP_LOUT
HP_ROUT