Abnormal Voltage (Dtv+9V Line) - Panasonic PT-50LCZ70 Service Manual

Protection Circuit
SOS terminal of IC6004 (TV microcontroller)
6
9
10
IC1107
11
+5V
1 2
REG.
IC1104,
Q1106
DC-DC
CONVERTER
Q6008
7
Error Information
29
LAMP FAN SOS :APPROX. 0V
OPT FAN SOS :APPROX. 0.5V
FRONT FAN SOS :APPROX. 1.3V
REAR FAN SOS :APPROX. 2V
NORMAL :APPROX. 2.8V
REAR JACK P.C.B. :APPROX. 3.3V
CONNECTION ERROR
[POWER Indicator one blink]
T1002
FULL-WAVE
10 8
RECTIFIER
11 9 11
POWER
TRANS.
IC1001
SWITCHING
2 9 14
CONTROL
(FEEDBACK LOOP)
R1017
IC1002 IC1003
R1018
FEED SHUNT
3 1
BACK REG.
R1019
POWER P.C.B.
[POWER Indicator two blinks]
IC6004 (TV MICROCONTROLLER)
DTV+9V SENS
MAIN P.C.B.
IC6004 (TV MICROCONTROLLER)
AC STOP(L)
12
DTV+9V SENS (SOS(L))
30
SUB+5V SENS (SOS(L))
34
MAIN+3.3V SENS (SOS(L))
57
LAMP RXD
67
FAN SOS
117
MAIN P.C.B.
Over voltage/current detection circuit
IC1107
(+9V)
9 9 +5V
1 2
REG.
11
IC1105
+1.8V
1 2
REG.
IC1104,
Q1106
DC-DC
CONVERTER
IC1103,
Q1107
DC-DC
CONVERTER
IC1202,
Q1201
DC-DC
CONVERTER
IC1201,
Q1202
DC-DC
CONVERTER
(Over voltage Detect)
Abnormal voltage (DTV+9V) detection circuit
Normal
SOS
30
SOS: 0V on DTV+9V line
PT-50LCZ70 / PT-56LCZ70 / PT-61LCZ70 / PT-50LCZ7 / PT-56LCZ7 / PT-61LCZ7
SOUND SOS (H)
72
PANEL SOS (L)
48
PANEL STATUS (SOS(L))
13
SOS (L)
114
IC1101,IC1102,
IC1205
Over current
Normal
Detect
Q1102
SW
MAIN P.C.B.
DTV+9V
9 9
10 10
11 11
13
IC4501
(AUDIO POWER AMP)
Q4502
SOUND SOS (L)
5
IC8001 (PEAKS)
PANEL SOS (L)
L6
PANEL STATUS (SOS(L))
G1
D1104,D1105,ETC
Q1102
OVER VOLTAGE
SW
DETECT CIRCUIT
IC1101,IC1102,
IC1205
OVER CURRENT
DETECT CIRCUIT
SUB+5V
SUB+1.8V
DTV+9V
SUB+3.3V
MAIN+3.3V
SUB+1.2V
FHD+3.3V
DDR+3.3V
FHD+1.2V
IC6004
(TV MICROCONTROLLER)
SOS
SOS (L)
114
+9V
POWER P.C.B.