Hello, I'm in possession of this 60 inch plasma, its power supply is defective, everything else is OK, very few people bought this TV so there's little I could find to help me.
I plug AC in, relay clicks ON and a second later it shuts down,repeats like this until i plug it off AC, PFC voltage is 305V stand-by and 384~386V during the cycling.
VA and VS go up to 0.42V.
P815 measures(STANDBY / ON / LABEL)
01 - 0V / 16.52V / 16.5V
02 - 0V / 16.52V / 16.5V
03 - GND
04 - GND
05 - 0V / 12.01V / 12V
06 - 0V / 12.01V / 12V
07 - GND
08 - GND
09 - 5.1V / 5.1V / 5V
10 - 5.1V / 5.1V / 5V
11 - 5.1V / 5.1V / 5V
12 - 5.1V / 5.1V / 5V
13 - GND
14 - GND
15 - GND
16 - GND
17 - 0V / 0V / 5VDET
18 - 5.02V / 5.014V / ACD(AC_detect)
19 - 0V / 0V / RL-ON
20 - 0V / 0V / VS-ON
21 - 0V / 0V / M5V_ON
22 - 5V / 5V / AUTO-GND
I also have M5V for the SUS boards and 5V in SMPSU main controller.
Force 5V into RL-ON or VS-ON pin doesn't change anything.
You see that I'm testing this board without main connected or screwed into the chassi, it is default behavior for LG plasma power boards to start-up in this condition.
I've replaced all optocouplers for confirmed working equivalent, replaced all ultrafast diodes(they were bad after 10 years of work), replaced 2 ceramic PTH capacitors, measured all PTH resistors / SMD capacitors / SMD resistors and they seem OK, desoldered and measured every transistor off the board,no bulging caps, everything looks good.
There are these 4 ICs on the primary side 1 KIA393P(dual OPAMP), SC6200(PWM), ICE1PCS02(PFC), SPF9001(no info) and the main microcontroller at secondary side, NEC D78F9234. When the SMPSU is plugged in AC SC6200 and KIA393P have 18V on their VCC pins, then the relay activates, ICE1PCS02 VCC pin gets 15V but it shuts down with the relay.
What seems to control VS is SPF9001(which is located on a soldered vertical daughter board) and on solder-side is a SMD IC SC6700(no info) that looks like control VA, there is one optocoupler to each one of them.
SMPSU part number is EAY41391501, no schematics to be found, all the service manual for 60PG30FD says is "replace power board", found two instances of repair kits including the SC6200.
I'm at a total loss,but I have an oscilloscope and a good DMM, can provide clear pictures of whatever is needed.
Service manual - https://www.electronica-pt.com/esque...s-pa81c-34623/
I plug AC in, relay clicks ON and a second later it shuts down,repeats like this until i plug it off AC, PFC voltage is 305V stand-by and 384~386V during the cycling.
VA and VS go up to 0.42V.
P815 measures(STANDBY / ON / LABEL)
01 - 0V / 16.52V / 16.5V
02 - 0V / 16.52V / 16.5V
03 - GND
04 - GND
05 - 0V / 12.01V / 12V
06 - 0V / 12.01V / 12V
07 - GND
08 - GND
09 - 5.1V / 5.1V / 5V
10 - 5.1V / 5.1V / 5V
11 - 5.1V / 5.1V / 5V
12 - 5.1V / 5.1V / 5V
13 - GND
14 - GND
15 - GND
16 - GND
17 - 0V / 0V / 5VDET
18 - 5.02V / 5.014V / ACD(AC_detect)
19 - 0V / 0V / RL-ON
20 - 0V / 0V / VS-ON
21 - 0V / 0V / M5V_ON
22 - 5V / 5V / AUTO-GND
I also have M5V for the SUS boards and 5V in SMPSU main controller.
Force 5V into RL-ON or VS-ON pin doesn't change anything.
You see that I'm testing this board without main connected or screwed into the chassi, it is default behavior for LG plasma power boards to start-up in this condition.
I've replaced all optocouplers for confirmed working equivalent, replaced all ultrafast diodes(they were bad after 10 years of work), replaced 2 ceramic PTH capacitors, measured all PTH resistors / SMD capacitors / SMD resistors and they seem OK, desoldered and measured every transistor off the board,no bulging caps, everything looks good.
There are these 4 ICs on the primary side 1 KIA393P(dual OPAMP), SC6200(PWM), ICE1PCS02(PFC), SPF9001(no info) and the main microcontroller at secondary side, NEC D78F9234. When the SMPSU is plugged in AC SC6200 and KIA393P have 18V on their VCC pins, then the relay activates, ICE1PCS02 VCC pin gets 15V but it shuts down with the relay.
What seems to control VS is SPF9001(which is located on a soldered vertical daughter board) and on solder-side is a SMD IC SC6700(no info) that looks like control VA, there is one optocoupler to each one of them.
SMPSU part number is EAY41391501, no schematics to be found, all the service manual for 60PG30FD says is "replace power board", found two instances of repair kits including the SC6200.
I'm at a total loss,but I have an oscilloscope and a good DMM, can provide clear pictures of whatever is needed.
Service manual - https://www.electronica-pt.com/esque...s-pa81c-34623/
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