Circuit Diagrams; Main Pwb Circuit Diagram - JVC LT-42HB1BU Service Manual

CIRCUIT DIAGRAMS

MAIN PWB CIRCUIT DIAGRAM (1/46) [TERRESTRIAL TUNER]
1
U921
FQD1116AME/BH
A
+5VT_ANT
L923
BLM18PG300SN1D
C922 C923
C921
220uF/16V/MVK/S
102p/50V/1005
104p/16V/1005
+5VTA
L921
BLM18PG300SN1D
C925 C926
C927
220uF/16V/MVK/S
104p/16V/1005 102p/50V/1005
+5VTA
B
L922
BLM18PG300SN1D
C929 C930
C931
220uF/16V/MVK/S
104p/16V/1005 102p/50V/1005
C
D
All location are from 921 to 960
1
2 3
IIC AS : Tuner : 0xC0h
Analog Demod : 0x86h
RF IN
R929
121/1005
R932
R933
R934
C932
C933
OPEN-330p/1005
OPEN-330p/1005
Antenna Power Short Protection Circuit
Antenna Current Limiting Circuit (100mA Limiting)
ANT_PWR_EN +5V_ANT
HIGH ON
LOW OFF
R922 330/1005
ANT_PWR_EN
MAIN PWB(7/46) R923 101/1005
ANT_PWR_CHK
IF ANT_PWR_CTRL is L
--> ANT_PWR_EN L
Fault Flag (Output):
Active-low, open-drain output.
Indicates overcurrent or
thermal shutdown conditions
2 3
(No.YA707<Rev.001>)2-9
4
25
GND
26
GND
27
GND
28
GND
R926
000/1005
RF_CVBS
R928
750/F/1005
R925
R940 201/1005
121/1005
C935
4R7p/50V/1005
R939 201/1005
R931 330/1005
000/1005
TUNER0_AGC MAIN PWB(26/46)
000/1005
000/1005
C934
104p/16V/1005
+3V3DT
R924
103/1005
+5VTA +5VT_ANT
U922
1 8
EN OUT
2 7
FLG IN
3 6
GND OUT
R927 222/1005
4 5
NC ILIM
POWER SW MIC2544-1YMM
Current limit threshold is determined by
ILIMIT = 230V / RSET,
where : 154 < RSET < 2.29k
4
2-10(No.YA707<Rev.001>)
5
MAIN PWB(13/46)
DTT_IF_NARROW-
DTT_IF_NARROW-
MAIN PWB(26/46)
DTT_IF_NARROW+
DTT_IF_NARROW+
MAIN PWB(13/46)
SIF
+5VTA +3V3DT
R930 R921
Q925
FDV301N_NL
562/1005 562/1005
3 2
3 2
Q924
FDV301N_NL
C936
220p/50V/1005
MAIN PWB ASS'Y(1/46)
[TERRESTRIAL TUNER]
HU-71100006
5
6
A
B
TUNER0_SDA
MAIN PWB(26/46)
TUNER0_SCL
C
D
6
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