Lg 37lh55 Lcd Tv Presentation Training Manual 3z7335

37LH55 Direct View LCD

October, 2009

Updated 11/03/2009

OUTLINE 37LH55 Section 1 Information, Preliminary Matters, Specifications, LCD Overview, General Troubleshooting Steps, Signal Distribution, Disassembly Instructions and Voltages Section 2 Circuit Board Operation, Troubleshooting of : • Switch mode Power Supply • Ballast Board • Main Board New

• T-CON Board

P-DIM (Digital Dimming) Routed from the Main board to the T-CON to the Ballast.

• Ft Control Board

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Overview of Topics to be Discussed

37LH55 LCD Direct View Display Section 1 This Section will cover Information and remind the Technician of Important Safety Precautions for the Customers Safety as well as the Technician and the Equipment. Basic Troubleshooting Techniques which can save time and money sometimes can be overlooked. These techniques will also be presented. This Section will get the Technician familiar with the Disassembly, Identification and Layout of the LCD Display . At the end of this Section the Technician should be able to Identify the Circuit Boards and have the ability and knowledge necessary to safely remove and replace any Circuit Board or Assembly.

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Preliminary Matters (The Fine Print)

IMPORTANT SAFETY NOTICE The information in this training manual is intended for use by persons possessing an adequate background in electrical equipment, electronic devices, and mechanical systems. In any attempt to repair a major Product, personal injury and property damage can result. The manufacturer or seller maintains no liability for the interpretation of this information, nor can it assume any liability in conjunction with its use. When servicing this product, under no circumstances should the original design be modified or altered without permission from LG Electronics. Unauthorized modifications will not only void the warranty, but may lead to property damage or injury. If wires, screws, clips, straps, nuts, or washers used to complete a ground path are removed for service, they must be returned to their original positions and properly fastened.

CAUTION To avoid personal injury, disconnect the power before servicing this product. If electrical power is required for diagnosis or test purposes, disconnect the power immediately after performing the necessary checks. Also be aware that many household products present a weight hazard. At least two people should be involved in the installation or servicing of such devices. Failure to consider the weight of an product could result in physical injury.

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ESD Notice

(Electrostatic Static Discharge)

Today’s sophisticated electronics are electrostatic discharge (ESD) sensitive. ESD can weaken or damage the electronics in a manner that renders them inoperative or reduces the time until their next failure. Connect an ESD wrist strap to a ground connection point or unpainted metal in the product. Alternatively, you can touch your finger repeatedly to a ground connection point or unpainted metal in the product. Before removing a replacement part from its package, touch the anti-static bag to a ground connection point or unpainted metal in the product. Handle the electronic control assembly by its edges only. When repackaging a failed electronic control assembly in an anti-static bag, observe these same precautions.

REGULATORY INFORMATION This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a residential installation. This equipment generates, uses, and can radiate radio frequency energy, and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the is encouraged to try to correct the interference by one or more of the following measures: Reorient or relocate the receiving antenna; Increase the separation between the equipment and the receiver; Connect the equipment to an outlet on a different circuit than that to which the receiver is connected; or consult the dealer or an experienced radio/TV technician for help.

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LCD Direct View Overview Section Safety and Handling Regulations 1. Approximately 20 minute pre-run time is required before any adjustments are performed. 2. Refer to the Voltage Sticker on the Switch Mode Power Supply silk screening. (+/- ½ volt). 3. Be cautious of electric shock from the Backlight section, it uses high voltage AC. Check that the Power Supply and Drive Circuits are completely discharged because of residual current stored before Circuit Board removal. 4. C-MOS circuits are sensitive to static electricity. Use caution when dealing with these IC and circuits. 5. Exercise care when making voltage and waveform checks to prevent costly short circuits from damaging the unit. 6. Be cautious of lost screws and other metal objects to prevent a possible short in the circuitry. Especially when removing the T-CON and/or the Ballast.

Checking Points to be Considered 1. Check the appearance of the Replacement and Circuit Boards for both physical damage and part number accuracy. 2. Check the model label. model names and board model matches. 3. Check details of defective condition and history. Example: Oscillator failure dead set, etc…

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Basic Troubleshooting Steps Define, Localize, Isolate and Correct

•Define Look at the symptom carefully and determine what circuits could be causing the failure. Use your senses Sight, Smell, Touch and Hearing. Look for burned parts and check for possible overheated components. Capacitors will sometimes leak dielectric material and give off a distinct odor. Frequency of power supplies will change with the load, or listen for relay closing etc. Observation of the front Power LED may give some clues. •Localize After carefully checking the symptom and determining the circuits to be checked and after giving a thorough examination using your senses the first check should always be the DC Supply Voltages to those circuits under test. Always confirm the supplies are not only the proper level but be sure they are noise free. If the supplies are missing check the resistance for possible short circuits. •Isolate To further isolate the failure, check for the proper waveforms with the Oscilloscope to make a final determination of the failure. Look for correct Amplitude Phasing and Timing of the signals also check for the proper Duty Cycle of the signals. Sometimes “glitches” or “road bumps” will be an indication of an imminent failure. •Correct The final step is to correct the problem. Be careful of ESD and make sure to check the DC Supplies for proper levels. Make all necessary adjustments and lastly always perform a Safety AC Leakage Test before returning the product back to the Customer.

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37LH55 PRODUCT INFORMATION SECTION 37” Full HD 1080p 240Hz LCD TV (37.0” diagonal)

Introducing LG’s first HDTV with TruMotion™ 240Hz technology. Now you can watch blazing-fast action with virtually no motion blur in crystal clear detail. All of your favorite sports, action movies and video games in crystal clear, Full HD 1080p. It’s still an HDTV, but you might decide it’s something better.

This section of the manual will discuss the specifications of the 37LH55 LCD Direct View Display .

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37LH55 Basic Specifications

• TruMotion 240Hz • Intelligent Sensor Mode • Full HD 1080p HD Resolution • 80,000:1 Dynamic Contrast Ratio • 2.4ms Response Time (GTG) • 500 cd/m2 Brightness • Wide Color Gamut • Super IPS • Wide Viewing Angle • XD Engine® • 24p Real Cinema • ISFccc® Ready • Picture Wizard • AV Mode II (Cinema, Sports, Game) • 60,000 Hour Life (typical) • NTSC/ATSC Tuners with Clear QAM 10

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Basic Specifications (LOGO Familiarization) Page 1 Full HD 1080p Resolution Displays HDTV programs in full 1920 x 1080p resolution for a more detailed picture.

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Remote Control Familiarization

BOTTOM PORTION

TOP PORTION

p/n MKJ42519621 12

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Accessing the Service Menu REMOTE TOP PORTION

SIDE KEYS

To access the Service Menu. 1) Turn the Set On 2) Simultaneously, Press and “Hold” the Menu Key on the Side Key pad and Press and “Hold” the Menu Key on the Remote approximately 5 seconds. 3) If Customer’s Menu appears, continue to hold until it disappears. 4) The Service Menu appears

Note: It is possible, dependant upon the Software Version, a may be required to enter the Service Menu. If a is required, enter 0000 13

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Rear and Side Input Jacks Rear Input Jacks

Side Input Jacks

Main PWB Orientation

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37LH55 PRODUCT DIMENSIONS 37" 939.8mm

Wattage STBY: >1W

7-7/8" 200mm

14" 364mm

8-1/8" 206mm

3-13/16" 97mm

26-1/16" 662mm

3-5/8" 91.4mm

Center

23-1/2" 597mm

11-3/4" 298.5mm 13 1/16" 331mm

7-7/8" 200mm

Model No. Serial No. Side Label

Remove 4 screws to remove stand for wall mount

2-9/16" 65mm

Weight without Stand: 32 lb Weight with Stand: 35.9 lb

20-1/16" 510mm

15

11-11/16" 297mm

DISASSEMBLY and TROUBLESHOOTING SECTION This section of the manual will discuss Disassembly, Layout and Circuit Board Identification, of the 37LH55 LCD Direct View Television.

Upon completion of this section the Technician will have a better understanding of the disassembly procedures, the layout of the printed circuit boards and be able to identify each board. 16

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Removing the Back Cover

The Stand does not need to be removed Remove the 16 screws indicated. Pay attention to the size and type of screw as there are many different types. Putting in the improper screw when reassembling may Cause damage.

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Circuit Board Layout

Ballast p/n EAT60664401

BALLAST

T-CON p/n EAT60664401

T-CON

SMPS

LVDS

MAIN

LVDS

KEY BOARD

FRONT CONTROL (IR)

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POWER SUPPLY SECTION This set utilizes a Switch Mode Power Supply.

Input Voltages: AC Stand-By Output Voltages: • +5V (Stand By 5V) to the Main. Run Output Voltages:

Stand-By Output Signals:

• +5V (Stand By 5V) to the Main • 12V to the Main

• AC Det. (Releases reset on Main)

(Video Processing and T-CON B+)

• 24V to the Main (Audio B+)

• 24V to the Ballast

Run Input Signals from Main: • PWR-ON (Relay On Command) Brings the SMPS out of Stand-By

• INV-ON (In and Out to the Ballast) Turns on the Backlights

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Power Supply PWB Removal To Ballast board

P203

P201

Disconnect P201, P203, SK101 and AC In SK100.

To Main board

Remove the 6 screws indicated by the arrows.

Caution: Be careful when touching the back side of the Power Supply as some capacitors can still hold a charge. To Main Power Switch

SK101

SK100 AC In SK100

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Power Supply (Master Power Switch) Location MASTER AC SWITCH LOCATION (Bottom Left Side viewed from rear)

If the TV won’t come on, be sure to check the Master Power Switch before assuming a failure has occurred. On

Off

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Power Supply (SMPS) PWB Layout To Main

To Ballast

P201

P203 Pin 1

Pin 1

Pin 2

F501 3.15A/250V Run 380V STBY 168V From Hot Gnd

To Master Power Switch SK101

AC IN SK100

Hot Ground Shock Hazard

F100 5A/250V AC IN

L N

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37LH55 POWER SUPPLY START UP SEQUENCE AC In

1

Stand By 5V Reg

6

No AC Det in this model

PWR On

2

Other Circuits 5V General 6 Reset of Main Board

3

4

T-CON PWB 12V LVDS Along with Video On LVDS cable

8

12V Video Processing

MAIN PWB

Other Circuits

5V Q706 Switch

IC103

6 24V Audio

Power On

3

6

Other Regs

Inverter On Starts the Ballast. LED1 Lights first. Backlights Light 2nd.

INV On

Manipulates Backlights CN4

P203

Inv On

6

Reg For Micro

24V

12V/24V Regulators

12V 24V

7

12V

PWM-DIM

3.3V, 26.2V, -7.47V, 16.3V To Video

9

PWM-DIM Digital 10 Dimming

Q706 LVDS 12V Switch

LVDS Video

7

8

23

Cust Menu for Backlight and Picture Content Manipulate P-DIM P801

Tru-Motion LVDS Video

Power On (RL_ON)

Inv On/Off LVDS Control Microprocessor IC100 Also Video Processor

10

CN3

P800

12V

Ballast

24V B+ for the Ballast

8

Stand By 5V

IC704 3.3V

24V Regulator

8

6

P201

At point 4 TV is in Stand-By state. Energy Star compliant. Less than 1 Watt

6

5

Ft Control

Power Button Or Remote Key

To To Backlights

Main Power Switch

Bridge

CN1

POWER SUPPLY (SMPS)

Primary side fuse: Stand-By 156V Run 390V (Hot Gnd)

37LH55 P700 ON MAIN PWB TO SMPS P201 TURN ON CIRCUIT To pins 1, 2, 3 and 4 of P800 to T-CON

12V

Q706

L728

LVDS 12V TCON

6

3

5

4

L715

P201

n/c PWR Gnd Gnd Gnd Gnd

1 2

n/c PWR On

Gnd

3

Gnd

4

Gnd

5

Gnd

6

5V

7

12V Gnd Gnd

10

Gnd

11

Gnd

12

21.3V

12

20

11

21

14

22 23 24

12 11 14

CN1 3

21.3V

n/c INV.On A.DIM ERR Out n/c n/c

PWM-DIM

n/c 3.8V 1.8V 0V n/c 3.38V

20K

L706

R757 0Ω

R743 R726 0Ω 10KΩ

C726 220uF

9 10

GPIO 138

100 E5

Power On

Relay On GPIO 134

R257

0K

LVDS Control

5V_ST

GPIO137

12V C720 0.1uF

16

C722 47uF 24V

17 19 20

L704

INV ON/OFF

C721 68uF

R717 3.3KΩ

+5V General

Q702

C727 100Ω 68uF R714

IC100 Mstar

R719 1KΩ

R759 0Ω

R244 100Ω

G5 Inverter On/Off GPIO 136

R185 A.DIM 1.2KΩ

AB13

21

24

Error: If backlights fail to fire on the 4th attempt, this line goes high and power is turned off.

R707 4.7KΩ

R201 100Ω

CN3

CN1

R843 0Ω

PWM-DIM (PWM Dimming) Manipulates the Backlight Brightness via Customer’s OSD. Manipulates the Backlight Brightness via the video processor IC100. Darker Picture, Darker Backlights to facilitate improved Contrast Ratio. 0.6V ~ 3.3V Range

T-CON

8

GPIO 97

P800

A-DIM (Analog Dimming) Fixed Voltage 3

PWM 0 Error

E8

22 23

H5

L707

15

18

3.3V-ST

Power On/Off

11 12

R253 10KΩ

F6

R718 10KΩ

3.3V-ST

5V_ST

0K

R251 100Ω

R776 0Ω

8

14

19

CN4

7

0V

0.6V

0.6V

Q703

R727 10KΩ

Q704

Q705 5V_ST

R706 R703 R771

Q701

6

14 16

C711 15pF

R732 22KΩ

R740 47KΩ

0.2V

R729 10KΩ

5

13

Gnd

PWR ON

4

12V Gnd

6V

L709 L701

3

13 15

2

2

12V

18

P203

BALLAST

5V

17

24V

1.8V

5V

9

Gnd Gnd

3.8V

5V

8

SBY5V

4.98V

1

7

+5V General

R739 47KΩ

1

8

+5V

MAIN PWB P700

SMPS

L708

44

R189 100Ω

AB12

PWM 2

VBR-B

24

R245 100

Power Supply (SMPS) PWB Operational Troubleshooting Power Supply Troubleshooting Ac voltage is supplied to the Power Supply at Connector SC100. This set does not use AC Detect. The AC input generates a Hot Ground primary power supply that runs in two states, Stand-By (168) and Run (380V) measured at Fuse F501 from Hot Ground. This primary voltage develops all other voltages that are output from the SMPS. During Stand-By, the 5 Volt Standby (5V_ST) should be present at connector P201, Pins 7,8,9 or 10. If Missing remove AC Power and unplug Connector P201, apply AC Power and recheck for presence of 5V_ST. Loss of 5V_ST would be a SMPS Failure. Presence of 5V_ST would be an indication of a failure on the Main Board or possibly the Front PWB (IR) assembly. Suspect a possible short circuit loading the supply. to observe the Front Power Indicating LED this may save some time. A lit LED indicates the Stand-By 5V voltage is present and the Microprocessor is communicating with the front LED driver IC! The Main Board sends two commands to the Power Supply Board one being PWR the other is INV ON. These two signals are used to control the SMPS turn on sequence. First the command PWR (Pin 2) also known as POWER ON, activates the Ballast voltage 24V and the 24Vt and 12V lines to the Main board. The 2nd command is INV ON (P201 pin 20). It is the Lamp Lighting Command Signal. If either command (PWR-ON or INV-ON) is missing it will result in a no picture symptom and the backlights will not turn on. These voltages can easily be checked with the volt meter! Remove AC Power, unplug the Connector to the Ballast P203. Reapply AC Power and press the ON-OFF Button on either the Remote Control or Power Button on the Unit. Watch for the Power ON LED to change color from red to blue. This is an indication the PWR Signal was created on the the Main board. Check P700 or P201 pin 2 for the PWR-ON command (4.9V) to the Power Supply. Check P201 for 24V (Pins 17 or 18) and 12V (Pins 13 or 14). Confirm Pin 20 of P201 went to 4.8V. This is the INV ON signal needed to light the Lamps. Problems with either voltage can be easily solved by following the simple steps on the next page.

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Test 1 Power Supply PWB Low Voltage Test AC Should not be applied at any time while adding resistors or while unplugging connectors as damage to the circuit PWB may occur. a) The SMPS PWB “MUST” be producing STBY 5V on either pin 7, 8, 9 or 10 (5V). If 5V Standby is not being generated, the SMPS PWB is defective and must be replaced. There is no need to continue with the next test. (b) Unplug P700 on the Main PWB and P203 to the Ballast. TEST 1: (1) Add a 10K resistor between (5V STBY) pin 7, 8, 9 or 10 and Pin 2 (PWR). Apply AC. This will turn on the power supply. a) Check that the 24V and 12V power supplies are turned on, P201 (24V pins 17 and 18) (12V pins 13 and 14) and 24V to the Ballast P203 Pins 1~5. (2) Remove AC power. Reinsert the plug P203 to the Ballast. Use P700 Side to Insert resistors

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Test 2 Power Supply PWB Backlights Test P700 Connector disconnected from the Main PWB. Apply AC after adding jumper.

Continue if the 1st test was successful. Leave original 10K resistor in place. (3) Add another 10K resistor between (5V) pin 7, 8, 9 or 10 and Pin 20 (INV On). (4) Unplug the small ribbon connector CN1 (This floats P-DIM) (5) Apply AC Power. This simulates a Power On and Backlight On command. Backlights Normal: a) If all is normal, the backlights should turn on. Backlights Abnormal: b) Recheck connector P203 and confirm 24V on pins 1~5. 1) If low or missing, use diode mode to check the 24V line on Ballast connector CN1. If low, this indicates a shorted output FET). 2) If open, check the Ballast Fuse, possible Open. c) Confirm the INV On/Off line P203 Pin 10 is going to 3V. d) Confirm Pin 3 of CN1 has >2V. 1) If not, you will need to add 3V by adding a 10K resistor from 5V_ST to pin 3 of CN1. Backlights should light. REMOVE AC POWER: d) Check the connections to the Backlights. DO NOT check these when AC is applied as they carry 1.2Kv each.

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Use P700 Side to insert resistors

LCD DV

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Power Supply Connector P201 Voltage and Diode Check P201 Odd "SMPS" to P700 "Main PWB" 2

PDIM Pin 24 is not used by the Ballast. PDIM is routed through the T-CON in this set. This line will fluctuate.

STBY

Run

Diode Check

PDIM

0V

3.24V

Open

23

nc

nc

nc

nc

22

Err Out

0V

0V

Open

BR1

0V

1.67V

Open

20

INV.ON

0V

4.8V

Open

19

nc

nc

nc

nc

17-18

24V

0V

24.8V

0.73V

15-16

Gnd

Gnd

Gnd

Gnd

13-14

12V

0V

12.15V

Open

11-12

Gnd

Gnd

Gnd

Gnd

7-10

*5V

5.14V

5.09V

Open

3-6

Gnd

Gnd

Gnd

Gnd

2

PWR-ON

0V

4.99V

1.69V

1

nc

nc

nc

nc

Pin

24

21

1

BR1 (A-DIM) Pin 21 Fixed and not used

*

Stand By 5V

Label 2

1

Diode Check taken with meter in Diode Mode with all Connectors Removed

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Power Supply P203 to Ballast CN4 Voltage and Diode Check There are no Stand-By voltages.

P203 "SMPS" to CN1 "Ballast"

Pin

Label

Run

Diode Check

1-5

24V

24.83V

0.73V

6-10

Gnd

Gnd

Gnd

11

BR1

1.67V

Open

12

INV On/Off

3.45V

Open

13

PWM-DIM

3.40V

Open

14

Error

0V

Open

Diode Check taken with meter in Diode Mode with all Connectors Removed

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Power Supply Connector SK100 and SK101 Voltage and Diode Check Diode Check taken with meter in Diode Mode with all Connectors Removed

SK100 "SMPS" to AC IN Pin

Label

1

L

2

N

STBY

Run

120Vac

SK101 "SMPS" to MASTER POWER SWITCH Diode Check

Pin

Label

OL

1

n/a

OL

2

n/a

AC Voltage Readings Across Pins 1 and 2 for STBY and RUN.

SK101

Bottom Left of SMPS

STBY

Run

120Vac

Diode Check OL OL

AC Voltage Readings for either pin 1 or pin 2 in STBY and RUN with one lead on Neutral of SK101. With the Master Power Switch Closed (On) AC flows. When Open (Off) AC open and does not flow.

Power Switch

Neutral SK100 AC In

Live

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BALLAST SECTION

Ballast Board The Ballast receives it B+ from the Switch Mode Power Supply. 24V (CN1 pins 1~5) is delivered when the “Power On” command arrives at the SMPS. The Backlights are turned on with the “Inverter On” command arrives. INV-ON is sent from the Main board through the SMPS to the Ballast. The Backlights are manipulated by the control signal “P-DIM (Digital Dimming)” coming from the T-CON board via CN4 pin 3. 31

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General Backlight Information To Backlights Over 1.2KV

Currently, number of lamps “Unknown” Approx 12

Connection board

To Backlights Over 1.2KV Connection board

Ballast Connection board

Connection board

To Backlights Over 1.2KV To Backlights Over 1.2KV

To Backlights Over 1.2KV

EEFL (External Electrode Fluorescent Lamp) LOW COST Large number of lamps driven by a single inverter 32

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Introducing EEFL Compared to CCFL Simple structure, Low price

Simple structure Complicated structure

Lamp manufacturing process Lamp assembly structure

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Low Cost Large number of Lamp Drive by single inverter

LCD DV

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EEFL Compared to CCFL Electrodes Key: Long Life Time

• For CCFL, Hg gas is consumed mainly near the internal electrode • For EEFL, longer life time is expected because there is no internal electrode consuming Hg gas

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Ballast PWB Assembly (With Shield) Layout

p/n EAY60713901 To Backlights Top Right

To Backlights Top Left The bright blue LED (LED1) assist the backlights in firing in low room light conditions.

Ballast Start Det LED (LED1)

Transformers

CN4 CN1

Transformers

To CN3 of T-CON

To P203 of SMPS

F1 10A/125V

To Backlights Bottom Right

To Backlights Bottom Left

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Ballast PWB Assembly Layout

Warning: Do not Run the Ballast with Shield Removed.

To Backlights Top Left

To Backlights Top Right

The bright blue LED (LED1) assist the backlights in firing in low room light conditions.

FET Drivers

Transformers CN4 Driver ICs CN1

Ballast Start Det LED (LED1)

F1 10A/125V

FET Drivers Transformers

To Backlights Bottom Right

To Backlights Bottom Left

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Ballast Transformer Waveforms Warning Do not Run the Ballast with Shield Removed.

FET Drivers 6

1

6

1

Primary Bottom Transformers Top Transformers are upside down

Warning, secondary is over 1.2Kv

34V p/p 48kHz

22.2V p/p 48kHz T1, T2, T3 or T4 Pin 1

T1, T2, T3 or T4 Pin 6

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37LH55 P700 on Main PWB To Power Supply P201 Out P203 To Ballast MCN1 1.2kV Out

P201

P203

CN1

7

BALLAST

8

P700 9

10

12

1

4.82V 24.83V

2

ERR

Ballast Driver 2

Drive signals To the FETs

2 3

4

4

5

5

14

0V 1.67V Fixed

13

14 11 13

20

24V

SMPS Controler

24V Reg

20

2

2

12V Reg

13

13

14

14

24V Reg

17

17

18

18

Hi if Lamps do not light A-DIM P-DIM not used

22

22

21

21

24

24

CN4

4.82V L701

PWR 2.86V

12V

24V

ERR 0V

R713 0Ω

R237 100Ω

G5 Inverter On GPIO136

R714 100Ω

E5 Relay On R706 R703 R771 20KΩ 0Ω 0Ω

R257 100Ω

GPIO131

Q701 R776 0Ω

R720 10KΩ

ERROR 4th time this line goes high, power shuts off.

5V_ST

R201 100Ω

R707 4.7KΩ

1.67V A-DIM (Analog Dimming) Fixed Voltage 1.67V

R185 1.2KΩ

PWM-DIM

3

PWM-DIM (PWM Dimming) Manipulates the Backlight Brightness via Customer’s OSD. Manipulates the Backlight Brightness via the video processor IC100. Darker Picture, Darker Backlights to facilitate improved Contrast Ratio. 0.6V ~ 3.3V Range

E8

GPIO97

AB13

VBR-A PWM-0

AB12

VBR-B PWM-2

R189 100Ω

R843 0Ω 44

P800

8

CN1

LVDS Cable

38

IC100 Mstar

3.3V_ST

R719 10KΩ

Q702

n/c

3

1.2kV Out

1

5V General R717 3.3KΩ

INV On/Off

12

3

11

Ballast Driver 1

Stby 5V

POWER SUPPLY

INV On/Off

24V

MAIN PWB

CN3 T-CON PWB

37LH55 BACKLIGHT DRIVE SIGNAL (Digital Dimming Effects)

Waveform taken from either of the two pins 1 or 6 of the Ballast Transformer on the Primary Side. Slow scope setting to 2.5mS to see PWM results. The PWM amount can cause the frequency to be measured differently.

48Khz 120Hz 700uS PWM-DIM manipulates the Burst Triangle Oscillator in the ballast drive IC. ADIM also manipulates the Burst Triangle Oscillator But it is not used.

7.7mS 80% on Backlight Bar In Customer’s OSD (3.0V PDIM Pin 13 MCN1)

3.3mS 5.2mS 50% on Backlight Bar In Customer’s OSD (2.0V PDIM Pin 13 MCN1)

5.3mS 3.2mS 20% on Backlight Bar In Customer’s OSD (1.22V PDIM Pin 13 MCN1)

39

Ballast Removal (Heat Sink and Insulators) Be sure to replace “All” heat sink materials.

Shield Flipped over

Remove 5 screws.

Heat Transfer material Protects the Output FETs Heat Transfer material

Do not Run the Ballast with Shield Removed. Be careful not to drop these screws.

40

October 2009

LCD DV

37LH55

Ballast Connector CN1 and CN4 Voltage and Diode Check There are no Stand-By voltages. CN1 "Ballast" to P203 "SMPS"

Pin 13 PDIM (Digital Dimming) This pin is not used. See CN4

Pin

Label

Run

Diode Check

1-5

24V

24.83V

0.73V

6-10

Gnd

Gnd

Gnd

11

BR1

1.67V

Open

12

INV On/Off

3.45V

Open

13

PWM-DIM

3.40V

Open

14

Error

0V

Open

CN4 "Ballast" to CN3 “T-CON"

Pin 3 PDIM (Digital Dimming) Can vary according to the brightness level of the video signal and the OSD Backlight setting. 0.6V 0% to 3.3V 100%. Output from the Video Processing chip IC100 (Mstar).

Pin

Label

Run

Diode Check

1

Gnd

Gnd

0.73V

2

C_1

Gnd

Gnd

3

C_2

*3.3V

Open

4

n/c

Gnd

Gnd

Diode Check taken with meter in Diode Mode with all Connectors Removed

41

October 2009

LCD DV

37LH55

T-CON (TFT DRIVE) SECTION

LCD Controller Board The T-Con IC UC1 receives from the Main Board LVDS at CN1 and CN2. This is a duel 24 Bit LVDS Video Signal which it processes into TFT Drive Signals which are delivered through connectors CN4 and CN5 to the LCD TFT . 12V is supplied to the T-Con Board on connector CN1 from the Main Board easily measured at fuse F1, (3A and 125V). There is a DC to DC converter that creates; (16.3V Measured at VDD). (26.2V Measured at D5 cathode). (3.3V Measured at VCC). (-7.47V Measured at D6 bottom left leg). These Voltages can also be measured at the ribbon connectors delivering signals to the TFT (CN4 26.2V pin 8, -7.4V pin 11, 3.3V pins 53, 54 and 16.3V pins 56, 57). (CN5 26.2V pin 7, -7.4V pin 6, 3.3V pins 53, 54 and 16.3V pins 56, 57). See the 11X17 Foldout (Interconnect Diagram) for more details. 42

October 2009

LCD DV

37LH55

T-CON (TFT Drive) PWB (With Shield) Remove the 2 Screws in the T-CON shield.

, these two screws have to be replaced in the board if the TV is to be run without the T-CON shield in place.

Note: There are Chocolate (Heat Transfer) material pieces on the back side of the T-CON Heat sink. They dissipate heat from the UC1 and US3 ICs. Be sure to return these pieces when Reinstalling the Heat Sink (Shield).

Heat Transfer

Heat Transfer

43

October 2009

LCD DV

37LH55

T-CON (TFT Drive) PWB Removal

T-CON p/n: EAT60664401

to reinstall the 2 screws for the Service Position if the T-CON board needs to be turned on for test purposes. These would have been removed when taking off the shield. CN5

Disconnect CN1, CN2, CN4 and CN5. See next slide for details.

CN4

U3 U2

UC1

U5 U4

CN3

CN1

CN2

44

October 2009

LCD DV

37LH55

T-CON (TFT Drive) PWB Removal Continued UNLOCKING CN1, CN4 and CN5 To remove the LVDS cable CN1; Press in on the two tabs and slowly rock the cable out of the connector. (Shown by the arrows in Fig 3)

To remove the flex cables to the TFT , CN4 or CN5: Place a soft thin object like a fingernail underneath the black locking tab and gently pull forward. (Shown by the arrows in Fig 1)

Fig 3 (CN1) LVDS CN4 or CN5 Locked Fig 1

Press In

Press In Pull Out

Flip the lock up and back from the flex cable. Then the flex cable can be easily removed.

Fig 4 (CN3) P-DIM

Unlocked Fig 2 Pull Out The locking tab is flipped upward

45

October 2009

LCD DV

37LH55

T-CON (TFT Drive) PWB (Shield Removed) Components Identified p/n EAT60664401 3.3V U4

CN5

C39

C36

7 C38

56/57

6

26.2V

-7.47V

53/54

1) 1.15V 2) 0.5V 3) 16.35V 4) 11.79V 5) 11.75V 6) Gnd 7) Gnd

8) 16.35V 9) 11.84V 10) 3.51V 11) 7.17V 12) 3.78V 13) 0V 14) 1.22V

15) 1.82V 16) 0V 17) 3.5V 18) 3.5V 19) 1.21V 20) Gnd 21) 11.84V

CN4 22) 11.84V 23) 11.82V 24) 0V 25) 3.33V 26) 11.02V 27) 11.85V 28) 1.22V

C40 C41 C42 C43

1) 7.06V 2) 16.27V 3) 2.36V 4) 13.4V 5) 0V 6) 11.14V 7) 10.4V 8) Gnd 9) 0V 10) 16.26V 11) 8.39V 12) 8.1V 13) 3.23V 14) 3.24V

16.3V

U2

U2

15) 6.89V 16) 16.27V 17) 2.36V 18) 3.11V 19) 0V 20) 16.29V 21) 16.27V 22) 5.25V 23) 6V 24) 0V 25) 0V 26) 0V 27) 0V 28) 3.25V

1.6V

1.2V

U5

U1 FL3 FL1 Gnd Pin 1, 2, 4

1.2V

FL4

FL5

CN3

P-Dim Pin 3

8) 0V 7) 3V 6) 0V 5) 3.25V

To UC1 Pin 192 P-Dim in Pin 8

53/54

3.3V

3.8V P/P 9.97Mhz

C

Q1 C

F1 (12V) 125V/3A

C

D3

C 16.3V VDD

12V A A 16V 16.34V

12V

12V Gnd

VCC L1

3.3V

CN2

Warning: T-Con PWB under shield. Be sure to reinsert screws before operating set with shield removed.

46

C69

C30

U4 D1

CN1

FL7 Gnd

L2

D2

A A Gnd 3.26V

16.3V

D4 20.5V

Q3

1) 6.9V 2) Gnd 3) 7.46V

C94

8.18V Q2 B E

D6

-7.47V

12V LVDS Pins 48-51

-2.79V C

Q4 8

26.2V

U3 A A 16.3V

26.2V

2.72V B 3.28V E

-7.47V

26.4V A 12.2V

X1

UC1

U1 1) 0V 2) 0V 3) 0V 4) 0V

3.24V

56/57

16.3V

C103 C102

Gnd FL6 Gnd

A

C

1) 6.9V 2) 7.47V 3) 7.47V

11

D5 26.6V

3.3V

16.3V

3.3V

T-CON (TFT Drive) PWB Checks

T-CON PWB (Locations)

Check the Regulator US2 for Correct Voltage

Gnd

US2 1.2V

Black band indicates Cathode

3.24V

D2

Cathode 16.34V

F1 D1

CN1 Check Fuse F1 for 12V from CN1 Pins 48, 49, 50, and 51.

Cathode 3.3V

Check Fuse F1 (12V)

47

October 2009

LCD DV

37LH55

T-CON (TFT Drive) Voltage Development Checks

The development for the voltages on the CN4 and CN5 connectors are shown here from the Interconnect diagram. They are outlined in the rounded cornered boxes.

48

October 2009

LCD DV

37LH55

T-CON PWB Connector CN1 to Main PWB Voltage and Diode Check CN1 CONNECTOR "T-CON PWB“ to P800 "Main" Pin

Label

Run

Diode Check

Pin

Label

Run

Diode Check

48-51

12V T-CON

12.06V

3.18V

23

URSA_A-3

1.3V

1.1V

41

URSA_B-4

1.3V

1.1V

22

URSA_A+3

1.3V

1.1V

40

URSA_B+4

1.3V

1.1V

20

URSA_ACK-

1.2V

1.1V

39

URSA_B-3

1.3V

1.1V

19

URSA_ACK+

1.1V

1.1V

38

URSA_B+3

1.3V

1.1V

17

URSA_A-2

1.1V

1.1V

36

URSA_BCK-

1.1V

1.1V

16

URSA_A+2

1.2V

1.1V

35

URSA_BCK+

1.2V

1.1V

15

URSA_A-1

1.3V

1.1V

33

URSA_B-2

1.3V

1.1V

14

URSA_A+1

1.3V

1.1V

32

URSA_B+2

1.3V

1.1V

13

URSA_A-0

1.3V

1.1V

31

URSA_B-1

1.3V

1.1V

12

URSA_A+0

1.3V

1.1V

30

URSA_B+1

1.3V

1.1V

11

OPC_OUT2

Gnd

Gnd

29

URSA_B-0

1.3V

1.1V

10

OPC_EN

0.6V

1.75V

28

URSA_B+0

1.3V

1.1V

9

OPC_OUT1

3.2V

1.75V

27

BIT_SEL

1.1V

1.1V

8

PWM-DIM

*3.2V

1.3V

25

URSA_A-2

1.3V

1.1V

7

LVDS_SEL

0V

1.95V

24

URSA_A+2

1.3V

1.1V

Pins 1, 18, 21, 26, 34, 37, 42, 43, 44, 45 and 46 are all ground. Pins 2, 3, 4, 5, 6 and 47 are all no connection.

*Pin 8 PWM-DIM 3.15V (Max 100%) to 0.6V (Min 0%) Customer’s Menu Backlight setting. Diode Check taken with meter in Diode Mode with all Connectors Removed

See arrow on the T-CON board CN1 indicating pin 1

49

October 2009

LCD DV

37LH55

T-CON PWB Connector CN2 to the Main PWB (Voltage and Diode Check) CN2 “T-CON“ to P801 CONNECTOR "Main" Pin

Label

Run

Diode Test

Pin

Label

Run

Diode Test

1-9

n/c

n/c

n/c

26

URSA-D+0

1.29V

Open

10

URSA-C+0

1.28V

Open

27

URSA-D-0

1.25V

Open

11

URSA-C-O

1.2V

Open

28

URSA-D+1

1.29V

Open

12

URSA-C+1

1.3V

Open

29

URSA-D-1

1.3V

Open

13

URSA-C-1

1.2V

Open

30

URSA-D+2

1.3V

Open

14

URSA-C+2

1.3V

Open

31

URSA-D-2

1.2V

Open

15

URSA-C-2

1.2V

Open

32

Gnd

Gnd

Gnd

16

Gnd

Gnd

Gnd

33

URSA-DCK+

1.23V

Open

17

URSA-CCK+

1.23V

Open

34

URSA-DCK-

1.29V

Open

18

URSA-CCK-

1.23V

Open

35

Gnd

Gnd

Gnd

19

Gnd

Gnd

Gnd

36

URSA-D+3

1.3V

Open

20

URSA-C+3

1.3V

Open

37

URSA-D-3

1.25V

Open

21

URSA-C-3

1.2V

Open

38

URSA-D+4

1.4V

Open

22

URSA-C+4

1.13V

Open

39

URSA-D-4

1.15V

Open

23

URSA-C-4

1.18V

Open

40-41

Gnd

Gnd

Gnd

24

Gnd

Gnd

Gnd

25

Gnd

Gnd

Gnd

Diode Mode values taken with all Connectors Removed

50

October 2009

LCD DV

37LH55

MAIN BOARD SECTION

Input Signal Processing IC100 is the main Microprocessor and the main Signal Processor. The Main board is responsible for : • • • • • • • • • • • • • •

ATSC, NTSC, and QAM reception and processing RS 232 service only Port (software upgrades and home theater environment). Wired Remote Port (2) Component Input Y, Pr, Pb and Audio L R (3) HDMI Inputs (back) (1) HDMI (Side Input) RGB PC and (PC Audio) USB (software upgrades using flash drive). USB located on the Side. AV Composite (1 Rear and 1 Side Input) SIF and SAP

Output Signals

Dual 20 Bit LVDS to the T-CON Board via P800 and P801. Including 12V T-CON. Audio output signals to the Speakers Digital Audio Output Coaxial and Optical ON OFF Controls to the SMPS turning on low voltage generation and Backlights Backlight intensity control signal (Digital Dimming) P-DIM sent to the T-CON board.

51

October 2009

LCD DV

37LH55

Removing the Main PWB

Flip the locking tabs upward, pull the LVDS ribbon up and out

Remove any tape holding down any cables.

P800 P801

Remove the 6 screws indicated by the arrows. Disconnect P700, P800, P801, P1200 and P600

NOTE: Be sure to check on top and behind the Video Processor IC. Look for a piece of Chocolate (Heat Transfer Material). Be sure to transfer to new PWB if present.

P800

P801

P700

P1200

P600

52

October 2009

LCD DV

37LH55

Main PWB Layout

VIDEO PROCESSOR IC100 RUNS HOT, THIS IS NORMAL. P800 to T-CON PWB

P801 to T-CON PWB

P700 To SMPS

To Front PWB Assembly

SW100 Reset

IC100 Microprocessor and Video Processor

P1200

P600 To Speakers

Look carefully on top and behind the Video Processor IC for Chocolate (Heat Transfer) material. Be sure to transfer to new PWB if replaced.

53

October 2009

LCD DV

37LH55

37LH55 Main PWB (Front View) Component Identification

P700 Q702 E

L726

IC704

LVDS

LVDS

P800

P801

B

Q706

C

L710

12V T-CON Pins 1~4

IC705

IC901

IC2 IC801 Tru-Motion

IC701

IC105

P104 N/C

X800 12Mhz

L718

IC900 IC1

IC100 Video Processor Mstar

IC706

P1200

Resets IC100

IC101

IC708 C

L712

B

Q100

B

B

IC1004 Tuner Ctrl

Q106

MAIN (Digital) Board

L607

E

To Speakers

P600

X100 12Mhz

IC1002

Y Pr/Pb 2

19 Video

IC502 HDMI Sel

L606

12345

LD1000

16 SIF 15 (5V)

Audio

HDMI2

Remote

TUNER TU1001

Optical

Y Pr/Pb 1

Audio

HDMI1

54

4 (5V)

C

RS232

Aud L

TDVW-H103F

Q1200 B E

Video

13 DIF 12 DIF +

RGB

HDMI3

AV In

HDMI4

X1005 25Mhz

Q1202 IC600 Audio

IC1001

USB

C C

1 2 3 4 5

IC1000

SW100 E

IC707

E

1

Aud R

37LH55 Main PWB (Back Side) Component Identification B E B E B E

Q705 Q704 Q703

IC800

C C C

2 1 3

IC107

Q701 C B

USB

IC104 IC901

IC1202

IC702

E B 2 1

3

HDMI4

D500 A A

D102 Q1001

C

C

IC501

E C B

E B

Q1000

A A

IC1201

A A

IC103 B

C E

D1240 D1238 D1239

Q105 C

C

D1204

C

Q600 IC1003

TUNER 19 Video 16 SIF 15 (5V) 13 DIF 12 DIF +

IC1200 A A

IC1203

IC601

C

D1223

TU1001 TDVW-H103F

4 (5V) 1

55

E

Main PWB X100 and X1005 Check IC100 Microprocessor Crystal

2.8Vp/p 12Mhz

2.28Vp/p 12Mhz

X100 1.62V Only when set is on

Set on or off 1.58V

1.6V X100 Location X800 Location

1.58V

X800 Crystal for TruMotion IC801 MAIN PWB

56

October 2009

LCD DV

37LH55

Main PWB X1005 and LD1000 Function LD1000

Only when set is on

1.56V

Use LD1000 as a visual aid. This lets you know if the tuner is receiving a signal. If illuminated, then there’s no signal. Normally this LED should be Off.

1.64V

X1005 Crystal for Tuner Controller IC1004 X1005 Location

Main PWB LD1000 Location

57

October 2009

LCD DV

37LH55

Main PWB Tuner with Shield Off (Pin ID) 19 18 13 12 9 8 4 1

58

October 2009

LCD DV

37LH55

Main PWB Tuner Video and SIF Output Check MAIN PWB Tuner Location

USING COLOR BAR SIGNAL INPUT

Note: “Video Out” Signal only when receiving an analog Channel.

Pin 19 “Video” Signal

Pi n

Pin 1 Pin 12 and Pin 13 “Dig IF” Signal

16 “

2.24Vp/p SI F” Si gn al

700mVp/p

450mVp/p

Note: “Dig IF” Signal only when receiving a Digital Channel.

59

October 2009

LCD DV

37LH55

Main PWB Tuner Clock and Data Lines Note: SCL and SDA only active during an actual Channel Change.

Pin 8 SDA

1V per/div

100uS

5V p/p

Pin 9 SCL

1V per/div

60

100uS

October 2009

5V p/p

LCD DV

37LH55

Main PWB LVDS P800 Video Output Check To confirm that the Main PWB is outputting Picture Content signals, check P800 (LVDS) cable for output. Check pins 11-14,16-17, 19-24, 27-30, 32-33 and 35-40. Pins 35-36 carry the clock for TA and 19-20 carry the clock for TB. These signals vary from each other, but looking for signals like the ones shown below on any of these pins will confirm the output of video content. This signal is using standard SMTE Color Bar output from a generator as the input source. Pin 51

P800

2uS

Pin 1

Pin 11

Pin 1, 2, 3, 4 (LVDS 12V)

500nS

P800 Location MAIN PWB

2uS

Pin 39 500nS

This is just a sample of two pins on the LVDS. There are 8 pins on P801 carrying video.

61

October 2009

LCD DV

37LH55

Main PWB Connector P700 to Power Supply Voltage and Diode Check P700 “Main” to P201 “SMPS” P700 STBY

Run

Diode Check

PDIM

0V

3.24V

1.25V

23

nc

nc

nc

nc

22

Err Out

0V

0V

Open

BR1

0V

1.67V

Open

20

INV.ON

0V

4.8V

Open

19

nc

nc

nc

nc

17-18

24V

0V

24.8V

Open

15-16

Gnd

Gnd

Gnd

Gnd

13-14

12V

0V

12.15V

2.3V

11-12

Gnd

Gnd

Gnd

Gnd

7-10

*5V

5.14V

5.09V

1.1V

3-6

Gnd

Gnd

Gnd

Gnd

2

PWR-ON

0V

4.99V

Open

1

nc

nc

nc

nc

Pin

24

21

1

Stand By 5V 1

Label 2

1

2

PDIM Pin 24 is not used by the Ballast. The voltage fluctuates, but is not used.

BR1 (A-DIM) Pin 21 Fixed and not used

Diode Check taken with meter in Diode Mode with all Connectors Removed

62

October 2009

LCD DV

37LH55

Main PWB LVDS Connector P800 Pin Identification P800 51

10bit TA or 10bit TB

1

Video Video

TB Clock

Video

Video

Video

Video

Resolution

TA Clock

12V for T-CON PWB

Pin 44 PDIM (Digital Dimming) Can vary according to the brightness level of the video signal and the OSD Backlight setting. 0.6V 0% to 3.3V 100%. Output from the Video Processing chip IC100 (Mstar).

63

October 2009

LCD DV

37LH55

Main PWB Connector P800 to T-CON Voltage and Diode Check Diode Check taken with meter in Diode Mode with all Connectors Removed

P800 "Main" CONNECTOR to CN1 "T-CON PWB“ Pin

Label

Run

Diode Check

Pin

Label

Run

Diode Check

1~4

12V T-CON

12.06V

3.18V

28

URSA_A+2

1.3V

1.1V

11

URSA_B-4

1.3V

1.1V

29

URSA_A-3

1.3V

1.1V

12

URSA_B+4

1.3V

1.1V

30

URSA_A+3

1.3V

1.1V

13

URSA_B-3

1.3V

1.1V

32

URSA_ACK-

1.2V

1.1V

14

URSA_B+3

1.3V

1.1V

33

URSA_ACK+

1.1V

1.1V

16

URSA_BCK-

1.1V

1.1V

35

URSA_A-2

1.1V

1.1V

17

URSA_BCK+

1.2V

1.1V

36

URSA_A+2

1.2V

1.1V

19

URSA_B-2

1.3V

1.1V

37

URSA_A-1

1.3V

1.1V

20

URSA_B+2

1.3V

1.1V

38

URSA_A+1

1.3V

1.1V

21

URSA_B-1

1.3V

1.1V

39

URSA_A-0

1.3V

1.1V

22

URSA_B+1

1.3V

1.1V

40

URSA_A+0

1.3V

1.1V

23

URSA_B-0

1.3V

1.1V

41

OPC_OUT2

Gnd

Gnd

24

URSA_B+0

1.3V

1.1V

42

OPC_EN

0.6V

1.75V

25

BIT_SEL

1.1V

1.1V

43

OPC_OUT1

3.2V

1.75V

27

URSA_A-2

1.3V

1.1V

44

PWM-DIM

*3.2V

1.3V

45

LVDS_SEL

0V

1.95V

*Pin 44 PWM-DIM 3.2V (Max 100%) to 0.6V (Min 0%) Customer’s Menu Backlight setting. The T-CON then routes P-DIM to the Ballast.

Pins 5, 46, 47, 48, 49 and 50 are all no connection. Pins 6,7,8,9,10, 15, 18, 26, 31, 34, and 51 are all ground.

(Pin 1) is on the right

64

October 2009

LCD DV

37LH55

Main PWB Connector P801 to the T-CON PWB Voltage and Diode Check P801 CONNECTOR "Main" to CN2 “T-CON" Pin 1-2

Label

Run

Diode Test

Pin

Label

Run

Diode Test

Gnd

Gnd

Gnd

19

URSA-C-4

1.18V

Open

3

URSA-D-4

1.15V

Open

20

URSA-C+4

1.13V

Open

4

URSA-D+4

1.4V

Open

21

URSA-C-3

1.2V

Open

5

URSA-D-3

1.25V

Open

22

URSA-C+3

1.3V

Open

6

URSA-D+3

1.3V

Open

23

Gnd

Gnd

Gnd

7

Gnd

Gnd

Gnd

24

URSA-CCK-

1.23V

Open

8

URSA-DCK-

1.29V

Open

25

URSA-CCK+

1.23V

Open

9

URSA-DCK+

1.23V

Open

26

Gnd

Gnd

Gnd

10

Gnd

Gnd

Gnd

27

URSA-C-2

1.2V

Open

11

URSA-D-2

1.2V

Open

28

URSA-C+2

1.3V

Open

12

URSA-D+2

1.3V

Open

29

URSA-C-1

1.2V

Open

13

URSA-D-1

1.3V

Open

30

URSA-C+1

1.3V

Open

14

URSA-D+1

1.29V

Open

31

URSA-C-O

1.2V

Open

15

URSA-D-0

1.25V

Open

32

URSA-C+0

1.28V

Open

16

URSA-D+0

1.29V

Open

33

n/c

n/c

n/c

17

Gnd

Gnd

Gnd

34-41

n/c

n/c

n/c

18

Gnd

Gnd

Gnd (Pin 1) is on the right

Diode Mode values taken with all Connectors Removed

65

October 2009

LCD DV

37LH55

Main PWB Connector P1200 to (Ft. IR/LED Control) Voltage and Diode Check P1200 CONNECTOR "MAIN PWB" to P1 "Front IR / LED PWB Assy"

1

Pin

Label

STBY

Run

Diode Check

1

SCL

1.5V

3.2V

Open

2

SDA

1.5V

3.2V

1.67V

3

Gnd

Gnd

Gnd

Gnd

4

Key1

3.3V

3.3V

1.4V

5

Key2

3.3V

3.3V

1.1V

6

5V ST

5.1V

5.0V

1.5V

7

Gnd

Gnd

Gnd

Gnd

8

Warm

Gnd

Gnd

Gnd

9

IR

3.9V

3.9V

Open

10

Gnd

Gnd

Gnd

Gnd

11

3.3V_ST

3.29V

3.29V

0.6V

12

POWER On/Off

0V

3.29V

Open

Diode Check taken with meter in Diode Mode with all Connectors Removed

66

October 2009

LCD DV

37LH55

Main PWB Connector P600 to Speakers Voltage and Diode Check P600 CONNECTOR "Main" to "Speakers"

Pin

LABEL

SBY

Run

Diode Check

1

SPK-R(-)

0V

12.4V

1.05V

2

SPK-R(+)

0V

12.4V

1.05V

3

SPK-L(-)

0V

12.4V

1.05V

4

SPK-L(+)

0V

12.4V

1.05V

Use speaker out to test for defective Audio Amp IC600

IC600 1

Diode Check taken with meter in Diode Mode with all Connectors Removed

67

October 2009

LCD DV

37LH55

FRONT IR AND KEY BOARD SECTION The Front IR board contains the Infrared receiver and the Power LEDs. This board receives its B+ (STBY5V) from the Main PWB. It also has connections to the side Key board. The 3.3V pull up for the keys is routed from the Main board through the Front IR board to the Side Key board. The Front Power LEDs pulsate or appear to move. This is accomplished using multiple LEDs and a driver IC U2 which communicates with the Main board via Clock and Data lines. There are several Zener diodes on the board as well and since it receives STAND-BY 5V (STBY 5V) it could make the Power Supply or the Main board appear to be defective if a short was introduced to the stand by line.

68

October 2009

LCD DV

37LH55

Front PWB Assembly (IR and Power LED) Layout (Front and Back View) To Main PWB

P2

Main Power SW

P1

1

1

P2 To Side Key PWB

P1

U2 LED Driver

To Main PWB

IR Sensor

Intelligent Sensor

Note: STBY5V is routed to this board. Be aware of a possibility for a short.

Power LEDs

69

October 2009

LCD DV

37LH55

Front PWB Assembly (IR and Power LED) Zener Check

ZD3 = 2.1V ZD1 = 2.2V ZD2 = 0.67V

ZD3 = 0.556V ZD1 = 0.712V ZD2 = Open

70

October 2009

LCD DV

37LH55

Front IR/LED Control Connector P1 and P2 to Main Voltage and Diode Check P1 Connector “IR/LED Control PWB“ to "MAIN PWB" P404 Pin

LABEL

STBY

Run

P2 Connector “IR/LED Control PWB“ to “Side Key" P3000

Diode Check

Pin

Label

STBY

Run

Diode Check

1

SCL

1.5V

3.2V

Open

2

SDA

1.5V

3.2V

Open

1

Key1

3.3V

3.3V

Open

3

Gnd

Gnd

Gnd

Gnd

2

Gnd

Gnd

Gnd

Gnd

4

Key1

3.3V

3.3V

Open

3

Key2

3.3V

3.3V

Open

5

Key2

3.3V

3.3V

Open

6

5V ST

5.1V

5.0V

2.3V

4

Gnd

Gnd

Gnd

Gnd

7

Gnd

Gnd

Gnd

Gnd

8

Gnd

Gnd

Gnd

Open

9

IR

3.9V

3.9V

Open

10

Gnd

Gnd

Gnd

Gnd

11

3.3V_ST

3.29V

3.29V

Open

12

POWER On/Off

0V

3.29V

Open

Diode Check taken with meter in Diode Mode with all Connectors Removed

71

October 2009

LCD DV

37LH55

SIDE KEY BOARD SECTION SW3001

SW3002 SW3003

SW3004 SW3005 SW3006 SW3007 1

SW3008

P3000

To Ft. Control

72

P3000

October 2009

LCD DV

37LH55

Side Key Assembly P3000 Information

P3000 Resistance Measurements with Key pressed.

1

KEY

Pin 1 measured from Gnd

KEY

Pin 3 measured from Gnd

Power

270.5 Ohms

Volume (-)

270.5 Ohms

Input

1.8K Ohms

Volume (+)

1.8K Ohms

Menu

4.8K Ohms

CH (Dn)

4.8K Ohms

Enter

10K Ohms

CH (Up)

10K Ohms

P3000 Voltage Measurements with Key pressed.

P3000

KEY

Pin 1 measured from Gnd

KEY

Pin 3 measured from Gnd

Power

0.179V

Volume (-)

0.179V

Input

0.906V

Volume (+)

0.906V

Menu

1.65V

CH (Dn)

1.65V

Enter

2.24V

CH (Up)

2.24V

P3000 Connector “Side Key" to “IR/LED Control PWB“ P1 Pin Label STBY Run Diode Check 1

Key1

3.3V

3.3V

Open

2

Gnd

Gnd

Gnd

Gnd

3

Key2

3.3V

3.3V

Open

4

Gnd

Gnd

Gnd

Gnd

73

October 2009

LCD DV

37LH55

Side Key Assembly Removal To remove the Key Board, there are two tabs that hold the board in place. Using a thin flat object, push the tabs to the right, first the bottom then the top to release the board.

Tab

Tab Push

Tab

Bottom board slot

74

October 2009

LCD DV

37LH55

INVISIBLE SPEAKER SYSTEM SECTION Invisible Speaker System Overview (Full Range Speakers) The 37LH55 contains the full progression of the Invisible Speaker system. First: The full range speaker layout is the basic system. The Full Range Speakers point downward, so there is no front viewable speaker grill or air ports. Main Speaker (Full Range Frequencies)

Tweeter (High Frequencies)

Magnet (Weight) Prevents vibrations

Reading across speaker wires, 8.2 ohm.

Tweeter p/n EAB58536001 15W 6OHM 0DB 0HZ 45X22X20

Full Range p/n EAB58304303 10W 8OHM 81DB 130HZ 130X50

75

October 2009

LCD DV

37LH55

Invisible Speaker System Overview (Tweeters) 2nd: Progression Elimination of the conventional speaker. Invisible Speaker has a sticky surface which adheres to front bezel. WARNING: Removing the Tweeter will destroy the speaker as shown above. The diaphragm/spider is glued to the front bezel. When removing, it will tear.

The front bezel is shown below. Note: the outlined circle is the location for the front sticky pad on the Invisible Speaker. This prevent the coil from bouncing off the plastic causing vibrations.

Tweeter p/n EAB58536001

Speaker Attachment post

Cabinet works as a diaphragm.

Outlined Circle

76

Invisible Speaker Tweeter shown separately. The Front (down) has sticky surface which adheres to front bezel. Note, there is no diaphragm, only voice coil.

October 2009

LCD DV

37LH55

Main Power Switch Note

ON

OFF

Pay attention to the Main Power Switch. Don’t forget to leave it in the On Position.

77

October 2009

LCD DV

37LH55

11 X 17 Foldout Section

This section shows the 11X17 foldout that’s available in the Paper and Adobe version of the Training Manual.

78

October 2009

LCD DV

37LH55

37LH55 INTERCONNECT DIAGRAM TO TFT MODULE To Backlight Top Right Side 1.2KV

CN3

CN6

Out Low

Low Out

T2

Do not run Ballast without heat sink attached

T4

6

1

p/n EAY60701701

PIN LABEL 1 Gnd C_1 2 3* C_2 4 n/c

Q5 Q6 Q19

35uF/680V

LED1 On then Off after ballast fires

Pin 1

22V p/p / 126kHZ

35uF/680V

Gnd 1.2V 3.24V

FL6 Gnd

U1 FL3 FL4 FL1

U5

1) 0V 2) 0V 3) 0V 4) 0V

FL5

P-Dim Pin 3

Gnd pin 3,7,10 P3000

For voltages See P1200

U4 Gnd

30

URSA_A+3

12 13

20

32

1.1V

1.3V

1.1V

19

33

URSA_ACKURSA_ACK+

1.2V

URSA_B-3

1.1V

1.1V

14

URSA_B+3

1.3V

1.1V

17

35

1.3V

1.1V

URSA_BCKURSA_BCK+

1.1V

1.1V

16

36

URSA_A-2 URSA_A+2

1.3V

1.1V

1.2V

1.1V

15

37

URSA_A-1

1.3V

1.1V

1.3V

1.1V

14

38

URSA_A+1

1.3V

1.1V

1.3V

1.1V

13

39

URSA_A-0

1.3V

1.1V

1.1V 1.1V

12

40

1.3V

1.1V

Gnd

Gnd 1.75V 1.75V

16

35 33

17 19

32

20

URSA_B-2 URSA_B+2

31

21

URSA_B-1

30

URSA_B+1

11

41

URSA_A+0 OPC_OUT2

29

22 23

1.3V 1.3V

URSA_B-0

1.3V

1.1V

10

42

OPC_EN

28

24

1.3V

1.1V

9

43

OPC_OUT1

27

25

URSA_B+0 BIT_SEL

0.6V 3.2V

1.1V

1.1V

8

44

PWM_DIM

*3.3V

1.3V

25

27

URSA_A-2

45

LVDS_SEL

0V

1.95V

28

URSA_A+2

1.1V 1.1V

7

24

1.3V 1.3V

VDD FL7 Gnd

12V

12V

D1

L1

3.3V

VCC

3.3V

A/C Rectifier 4A

IC600 ~ ~ +

L601

20 bit LVDS

Run

Diode Check

24

P-DIM

0V

3.24V

1.2V

nc

nc

nc

Err Out

0V

0V

Open

21

BR1

0.6V

1.67V

Open

20 19 17,18 15,16 13,14 11,12 7,8,9,10 3,4,5,6 2

INV.ON nc 24V Gnd 12V Gnd 5V Gnd PWR-ON

0V nc 0V Gnd 0V Gnd 5.1V Gnd 0V

4.8V nc 24.8V Gnd 12.15V Gnd 5.09V Gnd 4.99V

Open nc 0.73V Gnd Open Gnd Open Gnd 1.69V

1

nc

nc

nc

nc

LOC

nc

Gen PT #

D201, D254

FCH10A10

D251, D252 6 Q101, Q102 11 Q602

MBRF10100CT Gnd K6A60D

D602

F15NM60N FSU10B60 EL817 ICE3B0365J

SMPS TEST 2: Backlight test. (Connectors from Test 1 remain.) Jump pin 2 to pin 20 (INV-ON). Remove CN3 from the T-CON PWB to the Ballast. (All voltages and the Backlights should turn on). If not, confirm that pin 3 of CN1 on the Ballast is >3V. If not, with CN3 disconnected from T-CON, Jump pin 7,8,9 or 10 (5V) through a 100 ohm to pin 3 of CN1 on the Ballast.

TDVW-H103F 1

TU1001 Not Used Not Used

Q705 Q704

Q702

STBY

B2M2883 IC100 SMPS TEST 1: Low Voltage test. L6562A IC600 To Force Power Supply On. Disconnect P800 on Main PWB. Jump pin 7,8,9 or 10 (5V) to pin 2 using a 10K resistor. (Test Voltage Outputs 12V, and 24V).

P1

22

40

1.1V 1.1V

C30

Back of the board

IR Receiver Power Button

29

1.3V 1.3V

36

Label

IC500

Front PWB Assembly (Interface)

3.18V

URSA_B-4 URSA_B+4

2 3 4 5 6 7 8 9

Not Used 10 Not Used 11 12 Outputs On Digital Channels 13 14 15 16 Not Used 17 18 Outputs On 19 Analog Channels Shield 20

NC_1 NC-2 GND (1) +B (5V) RF-AGC NC-(VT)

B E B E B E

C C

EB1 2 C

C

IC704

L726

LVDS

LVDS

P800

P801

Q706 Q703

3

IC800

IC705

IC107 L710

IC105

P700

X800 12Mhz

IC2

IC901 IC801 Tru-Motion

IC701 IC706 L718

Q701

IC900

C E

IC1

B

P1200

D1240 D1238

Resets IC104 IC100

IC702 D1239

C B

A A

IC101

Q105

E B

C C

E

2

L607 IC103 1

B

3

IC600 Q600 B Audio C

E

Q1202

E

L712

B

X100 12Mhz

D102

1 2 3 4 5

IC1000

Grayed out components are on the back side

LABEL

RUN

1

R-

13V

Diode Check 1.05V

2

R+

13V

1.05V

3

L-

13V

1.05V

4

L+

13V

1.05V

PIN

IC1003 L606 IC601 IC1002 12345

IC1201

E B

C E B

Audio

Y Pr/Pb 2

A C

HDMI3

HDMI2

Remote

Audio

+B (2) SIF AUDIO_OUT VIDEO_OUT

Video

TUNER TU1001 TDVW-H103F

Aud L

Aud R

4 (5V)

C

RS232

HDMI1

LD1000 Lights when tuner OK

13 DIF 12 DIF +

Optical B E

C

IC501

16 SIF 15 (5V)

IC1203

A

D1223 RGB

Q1200 Y Pr/Pb 1

LD1000

19 Video

IC1200

1

DIF (+) DIF (-) IF_AGC

NC-4

C

Q1001 IC502 HDMI Sel

D500 A A

Q1000

AV In

GND (2) SDA SCL AS NC-3

IC1001 IC1004 Tuner Ctrl

P600 "MAIN" to “Speakers”

P600

IC1202

X1005 25Mhz

MAIN (Digital) Board

A A

IC707

E

IC901

Q106

C

IC708 C

Q100

SW100

D1204

C

IC100 Video Processor Mstar

P104 N/C

HDMI4

Gnd Gnd Gnd 3.3V 3.3V Open Gnd Gnd Gnd

All others Open

P2

D2

12V_TCON

11

R+ to R- 8.2 Ohm L+ to L- 8.2 Ohm

Gnd Key2 Gnd

Diode Check 2.3V pin 6

Diode Pin Label STBY Run Check 1 Key1 3.3V 3.3V Open 2 3 4

P1

Q1

1.1V 1.1V

1-4

41

C69

L2

1.3V 1.3V

48-51

16.3V

Pin

IC101, 501, 502

AC IN

16.34V

D6

Diode Test

Q3

12V A A 16V

Tuner Data

P3000 o P2 Front PWB

C101

To Backlight Bottom Right Side

D602

Q602

N

D3

20.5V

3.26V

16.3V

C

Run V

URSA_A-3

To Speakers

Grayed out components are on the back side 3.15A / 250V 335V (Hot Gnd) F501

F100 5A/250V

L

C

Pin ID

P800

USB

Power Supply

L102

16.34V

CN1 23

P201 “SMPS” to P700 “Main”

IC500

SK100

Q2

A A Gnd C

23

Primary

Q101

D4

8.18V B E

Run V Diode Test

39 38

Note: CN1 Pin 1 is P800 Pin 51

P201

Secondary

Q102

A 16.3V

F1 (12V) 125V/3A

D254

IC501

C104

Low Out CN5 1.2KV

To Backlight Bottom Left Side

2.72V B 3.28V E

22

1

C

-2.79V

1) 6.9V 2) Gnd 3) 7.46V

Pin ID

P800

12.06V

1) 6.9V 2) 7.47V 3) 7.47V

Q4

C94

C102

C

12V to T-CON Pin 48 ~ 51

D201

*PWM-DIM (Note this line is not used.) It is open (n/c) on the Ballast board.

CN1

8

P-Dim Pin 8

D252

IC101

C103

-7.47V

5V = 2.0A 12V = 2.0A 24V = 6.1A

T100

U3

CN2

Pin 3 PDIM (Digital Dimming) Can vary according to the brightness level of the video signal and the OSD Backlight setting. 0.6V 0% to 3.3V 100%. Output from the Video Processing chip IC100 (Mstar).

Main Power Switch

1.6V

CN1

CN3 Gnd Pin 1, 2, 4

P203 "SMPS" to CN4 "Ballast" PIN LABEL RUN Diode Check 1-5 VBL / 24V 24.83V 0.73V 6-10 Gnd Gnd Gnd 11 VBR-A BR1 1.67V Open 4.8V 12 INV On/Off Open 13 *PWM-DIM 3.24V Open 0V 14 Status/Error Open

26.6V

53/54 3.3V

56/57 16.3V

26.4V A A 12.2V

26.2V

12V LVDS Pins 48-51

26.2V

C43

A

D251

Side (Key) Controls

1.2KV

D5

P203

T3

Low CN2

C40 C41 C42

8) 0V 7) 3V 6) 0V 5) 3.25V

To pin 192 UC1

-7.47V 11 CN4

22) 11.84V 23) 11.82V 24) 0V 25) 3.33V 26) 11.02V 27) 11.85V 28) 1.22V

UC1

SK101

Out

15) 1.82V 16) 0V 17) 3.5V 18) 3.5V 19) 1.21V 20) Gnd 21) 11.84V

3.8V P/P 9.97Mhz

U1

1.2V

IC101

T1

U4

16.3V

C

IC502

6

8) 16.35V 9) 11.84V 10) 3.51V 11) 7.17V 12) 3.78V 13) 0V 14) 1.22V

3.3V

X1

LED1 assist the backlights in the firing process when ambient room light is minimal. Exciting the Selenium gas.

Q16 1

1) 1.15V 2) 0.5V 3) 16.35V 4) 11.79V 5) 11.75V 6) Gnd 7) Gnd

6 -7.47V

7 26.2V

n/c

- + F1 Q1 12A/65V Q2 Q18

6

39V p/p / 64Khz

C38

15) 6.89V 16) 16.27V 17) 2.36V 18) 3.11V 19) 0V 20) 16.29V 21) 16.27V 22) 5.25V 23) 6V 24) 0V 25) 0V 26) 0V 27) 0V 28) 3.25V

CN4

- + CN1

U2

LED1

Pin 6

- + 35uF/680V

U1

1) 7.06V 2) 16.27V 3) 2.36V 4) 13.4V 5) 0V 6) 11.14V 7) 10.4V 8) Gnd 9) 0V 10) 16.26V 11) 8.39V 12) 8.1V 13) 3.23V 14) 3.24V

Diode Check Gnd Gnd Open Gnd

Pin 1 or 6 of any transformer

CN5

U2

Note: Pin 3 is P-DIM from the T-CON. The T-CON receives P-DIM on CN1 pin 8 which is from the Main board via LVDS cable Main P800 pin 44. The T-CON outputs P-DIM on pin 3 of CN3 to CN4 on the Ballast board.

Q17

Ballast

RUN Gnd Gnd *3.3V Gnd

p/n EAT60664401

53/54

U2

CN4 "Ballast" to CN3 "T-CON"

6

1

Warning: T-Con PWB under shield. Put screws back in before operating set with shield removed.

3.3V

C36

1.2KV

16.3V 56/57

C39

To Backlight Top Left Side

Pins 6-10, 15, 18, 26, 31, 34 and 51 are all Ground. Pins 5 and 46-50 are not used.

P800 CONNECTOR "MAIN” AND CN1 T-CON PWB

TO TFT MODULE

P1200 CONNECTOR "MAIN PWB" to P1 "Front IR / LED PWB Pin

Label

STBY

Run

1

SCL

1.5V

3.2V

Diode Check Pin 1.8V

7

2

SDA

1.5V

3.2V

1.8V

8

Label

STBY

Gnd Warm

Gnd

Gnd

Gnd

Gnd

Gnd

Gnd

3.9V

3.9V

Open

3

Gnd

Gnd

Gnd

Gnd

9

IR

4

Key1

3.3V

3.3V

1.4V

10

5

Key2

3.3V

3.3V

1.4V

11

Gnd 3.3V_ST

6

5V ST

5.1V

5.0V

1.5V

12

POWER On/Off

Run Diode Check

Gnd Gnd 3.29V 3.29V 0V

3.29V

Gnd 0.6V Open

37LH55 MAIN (FRONT SIDE) ICs IC101 Pin [1] [2] [3] [4] [5] [6] [7] [8] IC105 Pin [1] [2] [3] [4] [5] [6] [7] [8]

Flash Memory from Boot for Saturn IC100 0V 3.2V 2.54V Gnd 0V 0V 3.24V 3.24V EEPROM Memory for Saturn IC100

IC701

1.8V DDR Reg Pin [1] [2] [3] [4] [5] [6] [7] [8]

IC704

Gnd Gnd 5V Gnd 3.24V 3.24V 5V 5V

+3.3V / +1.26_VDDC Pin [1] [2] [3] [4] [5] [6] [7] [8]

n/c (0V) 3.24V 3.24V n/c (0V) n/c (0V) 1.88V 0.8V Gnd +3.3V / +3.3V_MEMC

Pin [1] [2] [3] [4] [5] [6] [7] [8]

IC705

IC706

0.8V Gnd 4.96V 7.68V 4.9V 3.3V 3.3V 2V

0.8V Gnd 12V 6.63V 4.98V 4.98V 0V 5V

37LH55 MAIN (FRONT SIDE) TRANSISTORS AND DIODES Q100

WP Flash Memory Pin for Boot IC101 [B] 0V [C] 2.54V [E] Gnd

Q106

Reset Switch S100 Pin (Saturn) video processor [B] 0V [C] 3.29V [E] 0V

Q702

INV On driver Pin to P601 pin 20 [B] 0.07V [C] 4.8V [E] Gnd

Q706 Pin [1] [2] [3] [4] [5] [6] [7] [8]

Q1200

5V General Switch 12V LVDS Switch 5V 0.3V 12V 4V 12V 12V 5.0V 5.0V

IR Buffer RS232 Pin [B] 0.64V [C] 0V [E] Gnd

Q1202

5V Wireless Switch Pin Controls Q504 [B] 0V [C] 3.29V [E] Gnd

1.8V_MEMC Reg Pin [1] [2] [3] [4] [5] [6] [7] [8]

0.8V Gnd 5V 6.08V 4.96V 1.3V 1.3V 3.2V 5V EXT Regulator

Pin [1] [2] [3] [4] [5] [6] [7] [8]

IC707

IC708

Gnd 0.8V 1.3V 1.28V 1.8V 5V 1.28V 5V

+1.2V_PVSB Regulator Pin [1] [2] [3] [4] [5] [6] [7] [8]

0.9V Gnd 5V 6.47V 4.85V 1.86V 1.86V 4.89V 1.26V_MEMC Reg

Pin [1] [2] [3] [4] [5] [6] [7] [8]

IC1000

IC1001

n/c 3.4V 3.4V n/c n/c 1.2V 10.8V Gnd 3.3V-PVSB and FE Reg

Pin [1] [2] [3] [4] [5]

4.9V 4.9V Gnd 3.4V 1.2V

IC1002

Tuner 5V Reg Pin [1] [2] [3] [4] [5]

8.9V 1.93V 5V n/c Gnd

37LH55 MAIN (BACK SIDE) TRANSISTORS AND DIODES Q105

Power On Delay Pin [B] 0V [C] 1.97V [E] Gnd

Q600 Pin [B] 0V [C] 3.27V [E] Gnd Q701

Audio Mute for IC600

RL On driver Pin to P700 pin 2 [B] 2.93V [C] 4.98V [E] 5.08V

D1238

Key2 (Zener) Protect

Q703

5V General Switch Pin +5V Switch [B] 0.64V [C] 0V [E] Gnd

Q1000

SIF (Tuner) Sound Pin [B] 2.37V [C] Gnd [E] 3.02V

D500

IC501 PIV protect Pin [A1] 0V [A2] 3.28V [C] 0V

Q704

Switch Control Pin [B] 0V [C] 0.64V [E] Gnd

Q1001

SIF (Tuner) Sound Pin [B] 1.69V [C] Gnd [E] 3.2V

D1204

Moving LED Pin [A1] 0V [A2] 0V [C] 0V

Q705

Switch Control Pin [B] 0.64V [C] 0V [E] Gnd

D102

D1223

5V to IC1200 Pin [A1] 5V [A2] 0V [C] 4.79V

D1239

IR (Zener) Protect

(A) Gnd (C) 3.3V

Audio Mute (Route) Pin [A1] 0V [A2] 0V [C] 0.1V

D1240

Key1 (Zener) Protect

(A) Gnd (C) 3.3V

(A) Gnd (C) 3.3V

37LH55 MAIN (BACK SIDE) SIMICONDUCTORS IC103

Reset Pin [1] Gnd [2] 0V [3] 3.3V

IC104

IC501

BCM EEPROM Pin [1] [2] [3] [4] [5] [6] [7] [8]

Gnd Gnd Gnd Gnd 3.24V 3.24V 0V 3.24V

Pin [1] [2] [3]

Power Det for Micro Gnd 3.3V 4V

IC107

HDMI CEC Pin [1] [2] [3] [4] [5] [6]

IC601

IC702

IC800

SPI Flash Pin [1] [2] [3] [4] [5] [6] [7] [8]

3.21V 3.29V n/c n/c n/c 3.2V

1.8V_AMP Regulator Pin [1] Gnd [2] 1.8V [3] 3.24V

IC1003

3.3V_ST Regulator Pin [1] Gnd [2] 3.3V [3] 5.08V

IC1200

0V 1.3V 3.25V Gnd 0V 0V 3.25V 3.25V Tuner 9V Reg

Pin [1] 12V [2] Gnd [3] 8.9V RGB Serial Pin [1] [2] [3] [4] [5] [6] [7] [8]

Gnd Gnd Gnd Gnd 4.79V 4.79V 4.79V 4.79V

IC1201

RS232 Tx/Rx Pin [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16]

3.3V 5.3V 0V 0V (-5.28V) (-5.3V) (-5.3V) 0V 3.25V 0.14V n/c n/c 0V 5.37V Gnd 3.3V

IC1202

USB 5V Over Current Protection

Pin [1] [2] [3] [4] [5] [6]

4.9V Gnd 0V 0V 0V 4.93V

Pin [1] [2] [3] [4] [5]

1.59V 3.23V 0V 1.62V 3.23V

IC1203

37LH55 Direct View LCD

This concludes the 37LH55 training session.