Panasonic TH-42PX20U-P Service Manual page 191

14.3. PF-Board Block Diagram
!
AC CORD
AC100V
K2CG3DH00034
TH-42PX20U-P
PF-BOARD BLOCK Diagram
PF
Tuner Power Board
!
AC INLET
K2AH3H000028
!
F901
AC120V
4
NEUTRAL
GND
1
LIVE
PF1
F900
!
D920
C920
R928 R927
1
C926
2
R934
R935
C924 R929
D926
T8AH 250V
CF901
R901
C901
T8AH 250V
HOT
S901
CF902
DC187V
IC920
C928
POWER CONTROL
Latch-stop
UVLO
-
comp
+ + +
comp
- -
VUL
Vcc(start) Vcc(startup off)
OVP /Vcc(stop) /Vcc(startup on)
comp
+
R
-
Q
VOVP
S
Peak
Thermal
Current
Shutdown
Limit
Z/C
Zero Current
Detection
On Dead Timer
S
Stand-By
Q
Vref
R
S
IF/B
F/B
Restart
-
+ Timer
On Time Timer
C925
R925
R904
LF909
LF904
3 4 3 4
C902
2 2
1 1
D925
C922
4 5
Vcc
D
Startup
UVLO
comp
Startup
Burst Peak
Current
Limit
Soft
drive
GND
3
D922
R94
1
4
3 2
LF911
!
F902
K5D312BK00
T3.15AL 250
LF915
3 4
C915
2
1
HOT
COLD
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