Hitachi 32HDT50 Service Manual page 93

AVC3-U AV P.W.B
Reg. SI-3033LSA
Fuse F901
AC INLET
5A/125V
AC in
120V
To frame
GND
AVC3-U POWER P.W.B
PROTECTION CIRCUIT BLOCK DIAGRAM
Reg. SI-3090KM FE+9V
I907
Reg. SI-3090KM
V+9V-1
I909
Reg. SI-3090KM
V+9V-2
I908
STB+5V
STB+3.3V
I910
AC-Clock
Photo-
coupler
I905
Standby
Standby
rectifier
DC/DC converter
D902 H901
Relay
S901
Fuse F902
2.5A/125V
Main
rectifier
Main
Switching
D901
-regulator
T901
Switching Photo-
regulator coupler
I901 I902
LIVE COLD
Reg. TK11125CS
Reg. SI-3050LSA
Reg. SI-3050LSA
Reg. SI-3050LSA
Reg. SI-3033LSA
FE+30V
POWER1
+9.5V
Relay Protection
driver circuit
Q930 Q931, Q933
SW
Q932
(Detect
Voltage-down) D944 D947
<2.8V >5.7V
D942
<3.8V
D941
<3.8V
16V
DC/DC converter
I931, D950, L931
DC/DC converter
Error
I933, D949, L932
Amp.
DC/DC converter
Q934,
D938 I930, D959, L933
DC/DC converter
93
PT3-E/G AVC3-U
DV+3.3V
AV+2.5V
I904
FE+5V
I906
V+5V
I905
DVI+5V
IJ05
DVI+3.3V
IJ06
+3.3V +5.5V
(Detect
Voltage-over)
FE+30V
D948
>6.6V
+9.5V
D955
>9.5V
D+1.8V
+3.3V
+5.5V
FSTBY+5V
I932
FC4