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Power Supply Basic Operation - as monitor

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Power Supply Basic Operation AC Voltage is supplied to the SMPS Board at Connector SC101 from the AC Input assembly, routed to the Standby 5V supply. The STBY5V (standby) is B+ for the Controller chip on the back of the board (IC701) on the SMPS and output at P813 pins 13 and 14 then sent to the Main board for Microprocessor (IC1) operation (STBY 3.46V RUN 5.14V). When the Microprocessor (IC1) on the Main Board receives a "POWER ON" Command from either the Power button or the Remote IR Signal, it outputs a high (2.43V) called RL_ON at Pin 15 of P813. This command causes the Relay Circuit to close both Relays RL101 and RL103 routing AC to the Bridge Rectifier D101 which then routes the primary voltage to the PFC circuit (Power Factor Controller) 388V which can be read measuring voltage at Fuses F302 and F801 from "Hot" Ground. AC Detection (AC Det) is generated on the SMPS, by rectifying a small sample of the A/C Line and routed to the Controller (IC701) where it outputs at P813 pin 16 (4.44V) and sent to P301 to the Main Board where it is sensed and monitored by the Main Microprocessor (IC1). If AC Det is missing the set will come on, but shut off in 10 seconds. When RL_ON arrives, the run voltage +5V source becomes active and is sent to the Main Board via P813 (5.17V at pin 5, 6 and 7). The (Error Det) from the SMPS Board to the Main Board can be measured at pin 8 of P813 (2.85V STBY and 4.90V RUN), but it is not used. The RL-ON command also turns on the 17V (Audio B+) which is also sent to the Main Board. The 17V Audio supply outputs to the Main board at P813 pins 1 and 2 and used for Audio processing and amplification. The next step is for the Microprocessor IC1 on the Main Board to output a high (3.29V) on M_ON Line to the SMPS at P813 Pin 17 which is sensed by the Controller IC701, turning on the M5V line and outputs at P812 pins 9 and 10 to the Y-SUS board. The Controller (IC701) also uses the M_ON line to turn on the VA and the VS supplies. (Note there is no VS On Command in this set). VS is output at P812 to the Y-SUS board P210. (VA pins 6 and 7 and VS pins 1 and 2). Note: The Va is fused on the Y-SUS then routed out P203 to the X-Board Left. VS is also routed out of the Y-SUS P211 pins 4 and 5 to the Z-SUS P2. AUTO GND Pin 18 of P813: This pin is grounded on the Main board. When it is grounded, the Controller (IC701) works in the normal mode, meaning it turns on the power supply via commands sent from the Main board. When AUTO GND is floated (opened), it pulls up and places the Controller (IC701) into the Auto mode. In this state, the Controller turns on the power supply in stages automatically. A load is necessary to perform a good test of the SMPS if the Main board is suspect. 37 July 2010 50PJ350 Plasma

Section	Page
50PJ350 PLASMA TRAINING PACKAGE	1
OUTLINE	2
Overview of Topics to be Discussed	3
LG Contacts	4
Preliminary Matters (The Fine Print)	5
ESD Notice	6
Safety and Handling, Checking Points	7
Basic Troubleshooting Steps	8
50PJ350 PRODUCT INFORMATION SECTION	9
50PJ350 Specifications	10
50PJ350 Logo Familiarization Page 1 of 3	11
50PJ350 Logo Familiarization Page 2 of 3	12
50PJ350 Logo Familiarization Page 3 of 3	13
600Hz Sub Field Driving	14
50PJ350 Remote Control	15
50PJ350 Rear and Side Input Jacks	16
50PJ350 Dimensions	17
DISASSEMBLY SECTION	18
Removing the Back Cover	19
Circuit Board Layout	20
Connector Identification	21
Disassembly Procedure for Circuit Board Removal	22
Disassembly Procedure for Circuit Board Removal (2)	23
X Drive Circuit Board Removal Continued	24
Getting to the X Circuit Boards	25
Left and Right X Drive Connector Removal	26
TCP (Tape Carrier Package) Generic Removal Precautions	27
Left and Right X Drive Removal	28
CIRCUIT OPERATION, TROUBLESHOOTING AND CIRCUIT ALIGNMENT SECTION	29
Signal and Voltage Distribution Block Diagram	30
Panel Label Explanation	31
Adjustment Notice	32
SWITCH MODE POWER SUPPLY SECTION	33
Switch Mode Power Supply Overview	34
Power Supply Board Layout (Drawing)	35
Power Supply Circuit Layout	36
Power Supply Basic Operation	37
Power Supply Turn On Sequence	38
Power Supply Va and Vs Adjustments	39
Power Supply Static Test with Light Bulb Load	40
Power Supply Static Test (Forcing on the SMPS in stages)	41
SMPS Connector P813 Identification, Voltages and Diode Check	42
SMPS Connector SC101 and P812 Identification, Voltages and Diode Check	43
Y-SUS BOARD SECTION	44
Y-SUS Block Diagram	45
Y-SUS Board Layout	46
Y-SUS Board Component Layout Drawing	47
VSC and -VY Adjustments	48
Y-Drive Signal Overview	49
Locking on to the Y-Drive Waveform Tip	50
Observing (Capturing) the Y-Drive Signal for Set Up Adjustment	51
Set Up and Set Down Adjustments	52
Set Up Adjustment Too High or Low	53
Set Down Adjustment Too High or Low	54
Y-SUS Board Troubleshooting VScan	55
Y-SUS Board P212 Connector to P205 Lower Y-Drive (Logic and FG5V)	56
Y-SUS Board P212 to Lower Y-Drive P205 Logic Signals Explained	57
Y-SUS P212 Connector Diode Mode Testing	58
Y-SUS Floating Ground (FG 15V) and (FG 5V) Checks	59
Y-SUS 16V Generation Checks	60
P101 Y-SUS to Control Board Fuse Information	61
Y-SUS P113 and P114 Plug Information	62
Y-SUS P211 Plug Information	63
Y-SUS P101 to Control P111 Plug Voltage Checks	64
Y-DRIVE BOARD SECTION	65
Y-Drive Board Layout	66
Y-Drive Upper Layout	67
Y-Drive Lower Layout	68
Y-Drive Diode Check Scan and FG	69
Y-Drive Buffer Troubleshooting	70
Y-Drive Upper P110 Connector Voltage and Diode Check	71
Y-Drive Lower P204 Connector Voltage and Diode Check	72
Removing (Panel) Flexible Ribbon Cables from Y-Drive Upper or Lower	73
Incorrectly Seated Y-Drive Flexible Ribbon Cables	74
Z-SUS SECTION	75
Z-SUS Block Diagram	76
Z-SUS Board Component Identification	77
Z-SUS Board Drawing	78
Z-SUS Waveform	79
VZB (Z-Bias) VR201 Adjustment	80
Connector P2 to Y-SUS P211 Voltages and Diode Checks	81
Connector P1 to Control P102 Voltages and Diode Checks	82
CONTROL BOARD SECTION	83
Control Board Pictorial	84
Control Board Component Identification and Checks	85
Control Board Temperature Sensor Location (Chocolate)	86
Locking on to the Y-Drive or Z-Drive Waveform Tip	87
Checking the Crystal X101 “Clock” on the Control Board	88
Control Board Signal (Simplified Block Diagram)	89
Control Board Connector P111 to Y-SUS P101 Voltages and Diode Mode Checks	90
Control P111 to Y-SUS P101 Plug Information	91
Control Board LVDS P121 Signals	92
Control Board LVDS P121 Connector Voltages and Diode Check	93
Control Board P101 Connector Pin ID and Voltages	94
P161 Connector \	95
P162 Connector \	96
X BOARD (LEFT, RIGHT and CENTER) SECTION	97
X Board Additional Information	98
X Board TCP Heat Sink Warning	99
X Board Layout Primary Circuit Diode Check	100
TCP (Tape Carrier Package)	101
TCP Testing	102
TCP 3.3V B+ Check	103
TCP Visual Observation. Damaged TCP	104
Left X Drive P122 Connector from Y-SUS P203 Information	105
P121, P212, P211 and P331 X Board Connector (VA Diode Check)	106
MAIN BOARD SECTION	107
Main Board Layout and Identification	108
Main Board Drawing (Front Side) Component Layout	109
Main Board Drawing (Front Side) Component Voltages	110
Main Board (Back Side) Component Layout	111
Main Board (Back Side) Component Voltages	112
Main Board Tuner Explained	113
Main Board Crystal X1, X402 and X401 Check	114
Main Board P703 (Removing the LVDS or SMPS Cable)	115
Main Board P703 LVDS Video Signal Test Points	116
Main Board Plug P703 “LVDS” Voltages	117
Main Board Plug P704 to Ft IR Board	118
Main Board Plug P301 to Power Supply Voltages and Diode Check	119
Main Board Speaker Plug P801 Voltage and Diode Check	120
FRONT IR, POWER LED and SOFT TOUCH KEY PAD SECTION	121
Front Control (IR and Intelligent Sensor) Board and Power LED Board Location	122
Front Control Board Connector P100 Voltage and Pin Identification	123
Front IR Board Plug P101 to Soft Touch Keys (Voltages and Pin Identification)	124
SOFT TOUCH KEY PAD SECTION (Board Layout and Identification)	125
Soft Touch Key Pad	126
Soft Touch Key Pad Resistance and Diode Mode Checks	127
INVISIBLE SPEAKER SYSTEM SECTION	128
INTERCONNECT DIAGRAM (11 X 17 Foldout) SECTION	129
Circuit Interconnect Diagram	130
LVDS Video Signal Waveforms	132

Match case Limit results 1 per page

July 2010

50PJ350

Plasma

Power Supply Basic Operation

AC Voltage is supplied to the SMPS Board at Connector SC101 from the AC Input assembly, routed to the Standby 5V

supply. The STBY5V (standby) is B+ for the Controller chip on the back of the board (IC701) on the SMPS and output at

P813 pins 13 and 14 then sent to the Main board for Microprocessor (IC1) operation (STBY 3.46V RUN 5.14V).

When the Microprocessor (IC1) on the Main Board receives a “POWER ON“ Command from either the Power button or

the Remote IR Signal, it outputs a high (2.43V) called

RL_ON

at Pin 15 of P813. This command causes the Relay Circuit to

close both Relays RL101 and RL103 routing AC to the Bridge Rectifier D101 which then routes the primary voltage to the

PFC circuit (Power Factor Controller) 388V which can be read measuring voltage at Fuses F302 and F801 from “Hot”

Ground. AC Detection (AC Det) is generated on the SMPS, by rectifying a small sample of the A/C Line and routed to the

Controller (IC701) where it outputs at P813 pin 16 (4.44V) and sent to P301 to the Main Board where it is sensed and

monitored by the Main Microprocessor (IC1). If AC Det is missing the set will come on, but shut off in 10 seconds.

When

RL_ON

arrives, the run voltage +5V source becomes active and is sent to the Main Board via P813 (5.17V at

pin 5, 6 and 7). The (Error Det) from the SMPS Board to the Main Board can be measured at pin 8 of P813 (2.85V STBY

and 4.90V RUN), but it is not used. The

RL-ON

command also turns on the 17V (Audio B+) which is also sent to the Main

Board. The 17V Audio supply outputs to the Main board at P813 pins 1 and 2 and used for Audio processing and

amplification.

The next step is for the Microprocessor IC1 on the Main Board to output a high (3.29V) on

M_ON

Line to the SMPS at P813

Pin 17 which is sensed by the Controller IC701, turning on the M5V line and outputs at P812 pins 9 and 10 to the Y-SUS

board.

The Controller (IC701) also uses the

M_ON

line to turn on the VA and the VS supplies. (Note there is no VS On Command

in this set). VS is output at P812 to the Y-SUS board P210. (VA pins 6 and 7 and VS pins 1 and 2). Note: The Va is fused

on the Y-SUS then routed out P203 to the X-Board Left. VS is also routed out of the Y-SUS P211 pins 4 and 5 to the Z-SUS

P2.

AUTO GND

Pin 18 of P813: This pin is grounded on the Main board. When it is grounded, the Controller (IC701) works in

the normal mode, meaning it turns on the power supply via commands sent from the Main board. When

AUTO GND

floated (opened), it pulls up and places the Controller (IC701) into the Auto mode. In this state, the Controller turns on the

power supply in stages automatically. A load is necessary to perform a good test of the SMPS if the Main board is suspect.