Sharp LC-37A37M Schematic

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LC-37A37M

SERVICE MANUAL

No. S19W2LC37A37M

LCD COLOR TELEVISION

MODEL

In the interests of user safety (required by safety regulations in some countries) the set should be restored to its original condition and only parts identical to those specified should be used.

LC-37A37M

OUTLINE

This model is based on the LC-32A37M and partially modified. For the contents not covered in this Service Manual, accordingly, ple ase refer to the LC-32A37M (SY8U6LC32A37M)

Service Manual.

CONTENTS

OUTLINE AND DIFFERENCES FROM BASE MODEL

OUTLINE.............................................................i

DIFFERENCES FROM BASE MODEL...............i

SAFETY PRECAUTION

IMPORTANT SERVICE SAFETY PRE-

CAUTION...........................................................ii

PRECAUTIONS FOR USING LEAD-FREE

SOLDER ...........................................................iii

CHAPTER 4. REMOVING OF MAJOR PARTS

[1] REMOVING OF MAJOR PARTS...................4-1

CHAPTER 5. OVERALL WIRING DIAGRAM

[1] OVERALL WIRING DIAGRAM......................5-1

CHAPTER 6. PRINTED WIRING BOARD

[1] POWER UNIT................................................6-1

[2] INVERTER UNIT ...........................................6-4

CHAPTER 1. SPECIFICATIONS

[1] SPECIFICATIONS .........................................1-1

CHAPTER 2. OPERATION MANUAL

[1] OPERATION MANUAL..................................2-1

CHAPTER 3. DIMENSIONS

[1] DIMENSIONS ................................................3-1

Parts marked with " " are important for maintaining the safety of the set. Be sure to replace these parts with specified ones for maintaining the safety and performance of the set.

CHAPTER 7. SCHEMATIC DIAGRAM

[1] SCHEMATIC DIAGRAM................................7-1

Parts Guide

This document has been published to be used for after sales service only. The contents are subject to change without notice.

LC-37A37M

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LC37A37M

OUTLINE AND DIFFERENCES FROM BASE MODEL

ServiceManual

OUTLINE

This model is based on the LC-32A37M and partially modified. For the contents not covered in this Service Manual, accordingly, please refer to the LC-32A37M (SY8U6LC32A37M) Service Manual.

DIFFERENCES FROM BASE MODEL

LIST OF CHANGED PA RTS

Ref. No. Description LC-32A37M LC-37A37M Note

PRINTED WIRING BOARD ASSEMBLIES

MAIN Unit DUNTKF067FM05 DUNTKF067FM06 No Internal parts change R/C, LED Unit DUNTKF068FM01 ←← KEYUnit DUNTKF069FM01 ←← POWER Unit DUNTKF063FM03 DUNTKF064FM02 Changes INVERTER Unit DUNTKF071FM01 DUNTKF072FM01 Changes GND Unit RUNTKA550WJZZ - Abolish GND Unit (Top) - RUNTKA552WJZZ Addition GND Unit (Bottom) - RUNTKA553WJZZ Addition

LCD PANEL

R1LK315T3GW40W R1LK370T3GW40W Changes Refer to Parts Guide. POWER Unit (DUNTKF064FM02) Refer to Parts Guide. INVERTER Unit (DUNTKF072FM01) Refer to Parts Guide.

LC-37A37M

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LC37A37M

SAFETY PRECAUTION

ServiceManual

IMPORTANT SERVICE SAFETY PRECAUTION

Service work should be performed only by qualified service technicians who are thoroughly familiar with all safety checks and the servicing guidelines which follow:

WARNING

1. For continued safety, no modification of any circuit should be attempted.

2. Disconnect AC power before servicing.

BEFORE RETURNING THE RECEIVER (Fire & Shock Hazard)

Before returning the receiver to the user, perform the following safety checks:

3. Inspect all lead dress to make certain that leads are not pinched, and check that hardware is not lodged between the chassis and other metal parts in the receiver.

4. Inspect all protective devices such as non-metallic control knobs, insulation materials, cabinet backs, adjustment and compartment covers or shields, isolation resistor-capacitor networks, mechanical insulators, etc.

5. To be sure that no shock hazard exists, check for leakage current in the following manner.

• Plug the AC cord directly into a 110 ~ 240 volt AC outlet.

• Using two clip leads, connect a 1.5k ohm, 10 watt resistor paralleled by a 0.15µF capacitor in series with all exposed metal cabinet parts and a known earth ground, such as electrical conduit or electrical ground connected to an earth ground.

• Use an AC voltmeter having with 5000 ohm per volt, or higher, sensitivity or measure the AC voltage drop across the resistor.

• Connect the resistor connection to all exposed metal parts having a return to the chassis (antenna, metal cabinet, screw heads, knobs and control shafts, escutcheon, etc.) and measure the AC voltage drop across the resistor. All checks must be repeated with the AC cord plug connection reversed. (If necessary, a non polarized adaptor plug must be used only for the purpose of completing these checks.) Any reading of 0.74 Vrms (this corresponds to 0.5 mA rms AC.) or more is excessive and indicates a potential shock hazard which must be corrected before returning the monitor to the owner.

DVM

AC SCALE

1.5k ohm 10W

0.15µF

TEST PROBE

TO EXPOSED METAL PARTS

CONNECT TO KNOWN EARTH GROUND

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

SAFETY NOTICE

Many electrical and mechanical parts in LCD color television have special safety-related characteristics. These characteristics are often not evident from visual inspection, nor can protection afforded by them be necessarily increased by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified in this manual; electrical components having such features

are identified by " " and shaded areas in the Replacement Parts Lists and Schematic Diagrams. For continued protection, replacement parts must be identical to those used in the original circuit. The use of a substitute replacement parts which do not have the same safety characteristics as the factory recommended replacement parts shown in this service manual, may create shock, fire or other hazards.

LC-37A37M

PRECAUTIONS FOR USING LEAD-FREE SOLDER

Employing lead-free solder

• “All PWBs” of this model employs lead-free solder. The LF symbol indicates lead-free solder, and is attached on the PWBs and service manuals. The alphabetical character following LF shows the type of lead-free solder.

Example:

L Fa

Indicates lead-free solder of tin, silver and copper.

L F a/a

Using lead-free wire solder

• When fixing the PWB soldered with the lead-free solder, apply lead-free wire solder. Repairing with conventional lead wire solder may cause damage or accident due to cracks.

As the melting point of lead-free solder (Sn-Ag-Cu) is higher than the lead wire solder by 40 °C, we recommend you to use a dedicated soldering bit, if you are not familiar with how to obtain lead-free wire solder or soldering bit, contact our service station or service branch in your area.

Soldering

• As the melting point of lead-free solder (Sn-Ag-Cu) is about 220 °C which is higher than the conventional lead solder by 40 °C, and as it has poor solder wettability, you may be apt to keep the soldering bit in contact with the PWB for extended period of time. However, Since the land may be peeled off or the maximum heat-resistance temperature of parts may be exceeded, remove the bit from the PWB as soon as you confirm the steady soldering condition.

Lead-free solder contains more tin, and the end of the soldering bit may be easily corroded. Make sure to turn on and off the power of the bit as required.

If a different type of solder stays on the tip of the soldering bit, it is alloyed with lead-free solder. Clean the bit after every use of it. When the tip of the soldering bit is blackened during use, file it with steel wool or fine sandpaper.

• Be careful when replacing parts with polarity indication on the PWB silk.

Lead-free wire solder for servicing

Part No. Description Code

ZHNDAi123250E J φ0.3mm 250g (1roll) BL ZHNDAi126500E J φ0.6mm 500g (1roll) BK ZHNDAi12801KE J φ1.0mm 1kg (1roll) BM

iii

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LC37A37M

CHAPTER 1. SPECIFICATIONS

[1] SPECIFICATIONS

LC-37A37M

ServiceManual

Item

LCD panel

Resolution

Video Colour System PAL/SECAM/NTSC 3.58/NTSC 4.43/PAL 60

TV Function

Viewing angles H : 176º V : 176º

Audio amplifier

Speakers

Terminals Rear Antenna input

OSD language English/Simplified Chinese/Traditional Chinese/Arabic

Power Requirement AC 110 - 240 V, 50/60 Hz

Power Consumption 126 W (0.9 W Standby)

Dimensions

Weight

Operating Temperature 0°C - 40°C

As a part of policy of continuous improvement, SHARP reserves the right to make design and specification changes for product improvement without prior notice. The performance specification figures indicated are nominal values of production units. There may be some deviations from these values in individual units.

TV-Standard PAL: B/G, D/K, I SECAM: B/G, D/K, K/K

Receiving Channel

TV-Tuning System Auto Preset 99 ch

STEREO/BILINGUAL NICAM: B/G, I, D/K A2 stereo: B/G

INPUT 1

INPUT 2

INPUT 3

INPUT 4

INPUT 5 S-VIDEO in, VIDEO in, AUDIO in

INPUT 6 (PC input)

OUTPUT AUDIO out

RS-232C 9 pin D-sub male connector

without stand

with stand

without stand 12.5 kg

with stand 14.5 kg

Model

VHF/UHF 42.75 - 866.25 MHz

CATV S1 - S41ch (including Hyperband)

LC-37A37M

37" (940 mm) Advanced Super View & BLACK TFT LCD

1,049,088 pixels (1366 x 768)

NTSC: M

10W x 2

10 x 4 cm 2pcs

UHF/VHF 75

HDMI (HDMI input) (480I, 576I, 480P, 576P, 720P/50Hz, 720P/60Hz, 1080I/50Hz, 1080I/60Hz)

AUDIO in, COMPONENT in (480I, 576I, 480P, 576P, 720P/50Hz, 720P/60Hz, 1080I/50Hz, 1080I/60Hz)

15 pin mini D-sub, AUDIO in (common use with INPUT 1) (Ø 3.5 mm jack)

916(W)x595(H)x123(D)mm

916(W)x660(H)x255(D)mm

DIN type

1 – 1

LC-37A37M

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LC37A37M

CHAPTER 2. OPERATION MANUAL

[1] OPERATION MANUAL

1. PARTS NAMES

TV (Front/Side)

ServiceManual

POWER (On/Off) button

MENU button

TV/VIDEO button

Channel up( )/ down ( ) buttons

Volume up (+)/ down (-) buttons

Remote control sensor

OPC sensor

TV (Rear)

RS-232C terminal

INPUT 6 (PC) terminals

INPUT 5 terminals

OUTPUT terminals

INPUT 4 terminals

POWER indicator

Antenna input terminal

INPUT 3 terminals

INPUT 2 (HDMI) terminal

INPUT 1 (HDMI) terminal

2 – 1

AC INPUT terminal

2. REMOTE CONTROL UNIT

1 2

1 POWER (STANDBY/ON)

To switch the power on and off.

2 DISPLAY

Display the channel or input information.

30–9

Set the channel. TELETEXT mode: Set the page.

4 (Flashback)

Press to return to the previous selected channel or external input mode.

5WIDE

Change the wide image mode.

6 FREEZE

Freeze a motion picture on the screen.

7///(Cursor)

Select a desired item on the setting screen.

ENTER

Execute a command.

8 EXIT

Return to the default screen.

10 11

12 13

15 16

9 Colour (Red/Green/Yellow/Blue)

TELETEXT mode: Select a page.

10 AV MODE

Select an audio and video setting.

11 SLEEP

Set the Sleep timer.

0hr.30min. 1hr.00min.

Off

12 (Mute)

Press Mutes sound. Press again Restores sound. Mute will be cancelled after 30 minutes. However, the TV will not suddenly output loud sound as the volume level will be set to 0 automatically. Increase the volume level by pressing VOL +.

13 MPX

Select the sound multiplex mode.

14 VOL + /VOL -

Set the volume. (+)Increasethevolume. ( - ) Decrease the volume.

15 CH /C H

TV input mode: Select the channel. TELETEXT mode: Select the page. ( ) Increase the channel number. ( ) Decrease the channel number.

16 TV/VIDEO (INPUT SOURCE)

Select an input source.

17 PC

Directly select the PC terminal.

18 MENU

Display the menu screen.

19 RETURN

MENU mode: Return to the previous menu screen.

20 (TELETEXT)

Select the TELETEXT mode. (all TV image, all TEXT image, TV/TEXT image)

(Reveal hidden for TELETEXT)

TELETEXT mode: Display hidden characters.

(SUBTITLE for TELETEXT)

To turn the subtitles on and off.

(Hold) TELETEXT mode: Stop updating Teletext pages automatically. Press again to release the hold mode.

(Subpage)

Display the Teletext subpage directly.

(Top/Bottom/Full)

TELETEXT mode: Set the area of magnification.

2hr.30min.

1hr.30min.

2hr.00min.

LC-37A37M

3. ATTACHING THE STAND

• Before attaching (or detaching) the stand, unplug the AC cord from the AC INPUT terminal.

• Before performing work spread cushioning over the base area to lay the TV on. This will prevent it from being damaged.

Confirm the screws supplied with the TV.

Screws (x4)

(used in step 3)

Insert the stand base to the stand post on the

Soft cushion

bottom of the TV. ( )

Insert and tighten the 4 screws into the 4 holes

on the bottom of the stand base.( )

NOTE

• To detach the stand, perform the steps in reverse order.

Screw

Screw driver

2 – 2

LC-37A37M

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LC37A37M

CHAPTER 3. DIMENSIONS

[1] DIMENSIONS

390

ServiceManual

Unit: mm

660

595

916

819.6

460.8

74 123

380

255

200

3 – 1

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LC37A37M

CHAPTER 4. REMOVING OF MAJOR PARTS

ServiceManual

[1] REMOVING OF MAJOR PARTS

1. REMOVING OF REAR CABINET

1. Remove the 11 screws [1], 3 screws [2] and detach the Rear Cabinet.

Rear Cabinet

LC-37A37M

4 – 1

LC-37A37M

2. REMOVING OF CONNECTORS, SPEAKERS, STAND COVER ASS’Y AND STAND ASS’Y

1. Remove all the connectors from all the PWBs.

2. Remove 2 screws [1] and detach the Speaker-L and Speaker-R.

3. Remove the 2 screws [2], 4 screws [3] and detach the Stand Cover Ass’y.

4. Remove the 4 screws [4] and detach the Stand Ass’y.

POWER PWB Unit

MAIN PWB Unit

KEY PWB Unit

R/C, LED PWB Unit

Speaker-R

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䬌䎳䎧䬍

䬌䎶䎳䬍

䬌䎳䎚䎓䎓䎔䬍

INVERTER PWB Unit

Speaker-L

䬌䎮䎰䬍

䬌䎵䎤䬍

䬌䎶䎳䬍

䬌䎳䎕䎖䎓䎔䬍

䬌䎳䎛䎕䎓䎔䬍䬌䎳䎛䎕䎓䎕䬍

䬌䎦䎱䎔䬍䬌䎦䎱䎕䬍

䬌䎳䎛䎕䎓䎕䬍

䬌䎶䎳䬍

Stand Cover Ass'y

Stand Ass'y

4 – 2

3. REMOVING OF PWB UNITS

1. Remove the 1 screw [1] and detach the R/C, LED PWB Unit.

2. Remove the 6 screws [2] and detach the MAIN PWB Unit.

3. Remove the 4 screws [3] and detach the POWER PWB Unit.

4. Remove the 4 screws [4] and detach the INVERTER PWB Unit.

5. Remove the 1 screw [5] and detach the KEY PWB Unit.

6. Remove the 2 screws [6] and detach the SW Bracket.

7. Remove the 4 screws [7] and detach the VESA Angle.

LC-37A37M

KEY PWB Unit

MAIN PWB Unit

POWER PWB Unit

VESA Angle

3 4

INVERTER PWB Unit

R/C, LED PWB Unit

SW Bracket

Front Cabinet

4 – 3

LC-37A37M

4. REMOVING OF LCD PANEL UNIT

1. Remove the 4 screws [1] and detach the LCD Panel Unit from Front Cabinet.

Front Cabinet LCD Panel Unit

4 – 4

+ 26 hidden pages