Circuit Diagrams; Main Pwb Circuit Diagram - JVC LT-19DB1BU/AX Service Manual

CIRCUIT DIAGRAMS

MAIN PWB CIRCUIT DIAGRAM (1/28) [DVB-T+C TUNER]
1
A
+5VT_ANT
C922
L923 104p/16V/1005
BLM18PG300SN1D
C939
220uF/16V/MVK/S
+5VTA
L921
BLM18PG300SN1D
C927
B
220uF/16V/MVK/S
+5VTA
L922
BLM18PG300SN1D
C931
220uF/16V/MVK/S
C
D
All location are from 921 to 960
1
2
U921
FQD1116AME/BH
RF IN RF IN
C923
102p/50V/1005
C925 C926
104p/16V/1005 102p/50V/1005
C929 C930
104p/16V/1005 102p/50V/1005
C935
OPEN-330p/1005
Antenna Power Short Protection Circuit
Antenna Current Limiting Circuit (100mA Limiting)
ANT_PWR_EN
HIGH
LOW
ANT_PWR_EN
MAIN PWB (7/28)
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
(No.YA697<Rev.001>)2-7
3 4
IIC AS : Tuner : 0xC0h
25
GND
26
GND
Analog Demod : 0x86h
27
GND
28
GND
R926 000/1005
R928 750/F/1005
R944
331/F/1005
R952
OPEN-330/F/1005
C932
OPEN_3R3p/50V/005
R944 and R929 are located near by U921
R929
121/F/1005
R950 R951
OPEN-331
OPEN-331
R948 000/1005
IF0_NARROW-
R949 000/1005
IF0_NARROW+
R932 000/1005
TUNER0_AGC
R933 000/1005
R934 000/1005
C936
OPEN-330p/1005
+5V_ANT
+3V3DT
ON
R924
103/1005
+5VTA +5VT_ANT
OFF
U922
R922 330/1005
1 8
EN OUT
R923 101/1005
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
3 4
2-8(No.YA697<Rev.001>)
5
MAIN PWB (12/28)
RF_CVBS
C933
OPEN-104p/16V/1005
R947
MAIN PWB (12/28)
SIF
330/1005
C937
C934
OPEN-220p/50V/1005
220p/50V/1005
+5VTA +3V3DT
MAIN PWB
(26/28)
R930 R943
562/1005 562/1005
Q925
FDV301N_NL
3 2
3 2
Q924
FDV301N_NL
MAIN PWB ASS'Y (1/28)
[DVB-T+C TUNER]
HU-71100004
5
6
A
B
TUNER0_SDA
MAIN PWB (26/28)
TUNER0_SCL
C
D
6
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