50LN5420-TC (CHASSIS:LB36B) - LG TV Service Manual (repair manual). Page 28

THE    SYMBOL MARK OF THIS SCHEMETIC DIAGRAM INCORPORATES
SPECIAL FEATURES IMPORTANT FOR PROTECTION FROM X-RADIATION.
FILRE AND ELECTRICAL SHOCK HAZARDS, WHEN SERVICING IF IS 
ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR
THE CRITICAL COMPONENTS IN THE    SYMBOL MARK OF THE SCHEMETIC.

+1.8V_TU

R3760

0

HALF_NIM/IF_NON_FILTER

C3743
20pF
50V

OPT

R3741-*1

1K

TU_IIC_NON_ATSC_1K

TU_GND_A

R3704

100

R3740-*1

1K

TU_IIC_NON_ATSC_1K

R3735

33

+3.3V_TU

LNA2_CTL

C3742
20pF
50V

OPT

TUNER_RESET

L3703

CIS21J121

IF_P_MSTAR

R3758
82

OPT

R3736

33

TU_GND_A

DEMOD_SCL

IF_AGC_MAIN

TU3700

TDSS-G201D

TUNER_OPT

5

+B1[3.3V]

11

DIF[N]

2

RESET

10

DIF[P]

4

SDA

1

NC_1

9

IF_AGC

8

NC_3

3

SCL

7

+B2[1.8V]

6

NC_2

12

SHIELD

A1

A1

B1

B1

TU_SDA

+3.3V_TU

C3727

0.1uF

16V

R3733

100K

C3707
100pF
50V

FE_TS_VAL_ERR

C3716

0.1uF

16V

+1.8V_TU

C3708

0.1uF
16V

LNA_CTRL_2

C3738
0.1uF
16V

+3.3V_TU

R3732
100

IC3703

AP1117E18G-13 

2

OUT

3

IN

1

ADJ/GND

R3705

0

OPT

R3784

0

OPT

FE_TS_DATA[0]

TU_SCL

C3737
100pF
50V

+3.3V_TU

C3740

0.1uF

16V

TU_CVBS

TU_SIF

R3761

0

HALF_NIM/IF_NON_FILTER

BR_RESET_DEMOD

R3740

1.8K

TU_IIC_ATSC_1.8K

TU_GND_A

FE_TS_CLK

RF_SWITCH_CTL

C3702

0.1uF

16V

OPT

FE_TS_SYNC

IF_AGC_SEL

C3710

0.1uF

16V

LNA_CTRL_1

C3713
18pF
50V

C3701
0.1uF
16V

DEMOD_SDA

C3717

0.1uF

16V

+3.3V_TU

C3711
18pF
50V

R3741

1.8K

TU_IIC_ATSC_1.8K

C3725

0.1uF
16V

IF_N_MSTAR

+3.3V_Normal

C3723
22uF
6.3V

C3715
22uF
6.3V

R3766
1

C3741-*1

10uF 10V

CAP_X7R_MP

C3741
10uF

10V

CAP_10uF_X5R

85C

TU3700-*1

TDSS-H501F

TUNER_ATSC

5

+B1[3.3V]

11

DIF[N]

2

RESET

10

DIF[P]

4

SDA

1

NC

9

IF_AGC

8

ALIF_[P]

3

SCL

7

+B2[1.8]

6

ALIF_[N]

12

SHIELD

A1

A1

B1

B1

TU3702

TDSH-G501D

TUNER_ISOLATOR_DVB_1INPUT_H

5

+B1[3.3V]

11

DIF[N]

2

RESET

10

DIF[P]

4

SDA

1

NC

9

IF_AGC

8

CVBS

3

SCL

7

+B2[1.8V]

6

SIF

A1

A1

B1

B1

A2

A2

B2

B2

R3761-*1
10

HALF_NIM/IF_FILTER

R3760-*1
10

HALF_NIM/IF_FILTER

R3714

0

NON_ASIA

R3715

0

NON_ASIA

2012.06.21

should be guarded by ground

TUNER MULTI-OPTION

NC4_S7LRM

GLOBAL tuner block except EU and China

Pull-up can’t be applied 
because of MODEL_OPT_2

close to TUNER

close to TUNER

FE_BOOSTER_CTL

1. should be guarded by ground
2. No via on both of them
3. Signal Width >= 12mils
   Signal to Signal Width = 12mils
   Ground Width >= 24mils

close to the tuner pin, add,09029

Close to the tuner

TUNER_NON_EU

Size change,0929

14

FE_AGC_SPEED_CTL

GND seperation for ASIS tuner

CHANGE TO
10UF 10V X5R

CHANGE TO
6.3V 2012 X5R

CHANGE TO
6.3V 2012 X5R

HPF

LPF

Frequence

1

0

0

54MHz~350MHz

TW_FE_LNA FILTER_SETTING

CTRL_1

CTRL_2

0

350Hz~450MHz

450Hz~870MHz

Filter_Type

1

0

Through