Sharp lc20b2ea schematic

LC-20B2EA

SERVICE MANUAL

S92R1LC-20B2E

LCD COLOUR 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.

CONTENTS

» IMPORTANT SERVICE SAFETY PRECAUTION ..........................................................................................2

» SPECIFICATIONS ......................................................................................................................................... 3

» OPERATION MANUAL ..................................................................................................................................4

» DIMENSIONS ................................................................................................................................................5

» REMOVING OF MAJOR PARTS ...................................................................................................................6

» ADJUSTING PROCEDURE OF EACH SECTION ......................................................................................10

» TROUBLE SHOOTING TABLE ....................................................................................................................13

» CHASSIS LAYOUT ......................................................................................................................................18

» BLOCK DIAGRAM ....................................................................................................................................... 20

» OVERALL SCHEMATIC DIAGRAM .............................................................................................................22

» DESCRIPTION OF SCHEMATIC DIAGRAM .............................................................................................. 24

» SCHEMATIC DIAGRAM .............................................................................................................................. 25

» PRINTED WIRING BOARD ASSEMBLIES .................................................................................................48

» PARTS LIST ................................................................................................................................................. 52

» PACKING OF THE SET ............................................................................................................................... 65

LC-20B2EA

Page

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LC-20B2EA

Specifications

Service work should be perfomed only by qualified service technicians who are thor-

IMPORTANT SERVICE SAFETY PRECAUTION

oughly 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.

CAUTION: FOR CONTINUED PROTECTION AGAINST A RISK OF FIRE REPLACE ONLY WITH SAME TYPE FUSE. F1 (T1.25AL, 250V), F2 (T1.25AL, 250V), F6700 (1.25A,

A V

250V), F6701 (1.25A, 250V), F6702 (1.25A, 250V), F6703 (1.25A, 250V) AND F6704 (1.25A, 250V)

BEFORE RETURNING THE RECEIVER (Fire & Shock Hazard)

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

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 resisor.

• 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 nonpolarized adaptor plug must be used only for the purpose of completing these checks.) Any reading of 0.75V peak (this corresponds to 0.5 milliamp. peak AC.) or more is excessive and indicates a potential shock hazard which must be corrected before returning the monitor to the owner.

1. 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.

2. Inspect all protective devices such as non-metallic control knobs, insulation materials, cabinet backs, adjustment and compartment covers or shields,

DVM

AC SCALE

50k ohm

10W

isolation resistor-capacitor networks, mechanical insulators and etc.

3. 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,

0.15 µF

TEST PROBE

and connect the DC power cable into the receiver's DC jack. (Do not use an isolation transformer for this test).

• Using two clip leads, connect a 50k ohm, 10 watt resistor paralleled by a 0.15µF capacitor in series with all exposed metal cabinet parts and a known earth ground,

234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121

TO EXPOSED METAL PARTS

CONNECT TO KNOWN EARTH GROUND

SAFETY NOTICE

Many electrical and mechanical parts in LCD 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

and shaded areas in the

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.

components having such features are identified by “ å”

234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121

Replacement Parts Lists

and

SPECIFICATIONS

LC-20B2EA

TV/VIDEO

Volume ( )/(+)

CH (

)/( )

TV/VIDEO

(MAIN POWER)

Speaker

POWER/STANDBY indicator

A green indicator lights when the power is

on and a red indicator lights when in the

standby mode (the indicator will not light

when the main power is off).

Speaker

Remote sensor window

Remote sensor indicator

A red indicator blinks when the TV set

receives the remote control signal.

Upper control panel

To change the vertical

angle of the LCD TV set,

tilt the screen up to 5

degrees forward or 10

degrees backward. The

TV set can also be

rotated 50 degrees

horizontally. Please adjust

the angle so that the TV

set can be watched most

comfortably.

Note:

)/( ), and Volume ( )/(+) on the main unit have the same functions as the same buttons on the

remote control. Fundamentally, this operation manual provides a description based on operation using the remote

control.

TV/VIDEO, CH(

V-IN

-IN

-V

-IN 1

-IN 2

S-VIDEO

VIDEO

AUD

WER

PUT

DC13V

Carrying handle

POWER INPUT DC13V

AV-IN 1

(21pin Euro-SCART)

S-VIDEO

VIDEO

AUDIO (L)

AUDIO (R)

AV-IN 2

Antenna

AUDIO OUT (L)

AUDIO OUT (R)

Headphones

Rear view

Remote Control

TV/VIDEO

TEXT

REVEAL

HOLD

END

MENUSOUND

SUBTITLE

(Power)

OK, Programme Table

SUBTITLE

Displays the Teletext

Subtitle directly.

HOLD

Temporarily holds

the current Teletext page.

Mute

Yellow,

Timer function Menu

Green, Sound Menu

Cyan, Status Display

Turns on the status display

when the menu is not

displayed.

TV/VIDEO

Channel Select

Volume (+)/(-)

Flashback

Returns to the

previous channel.

Red, Picture Menu

Upwards/ Downwards

Selection, zoom display

function

(Teletext mode)

END

TEXT

SOUND

Switches the

sound mode.

REVEAL

Displays hidden

information such as

solutions to riddles and

puzzles.

Right / Left Selection

CH ( )/( )

Displays previous/

(Teletext mode)

OPERATION MANUAL

72.6

66.6

DIMENSIONS

188193.5

LC-20B2EA

Unit: mm

TV/VIDEO

379

630

72.6

107.3

468.8

473.5

381.5

298.8

401.3

AUDIO OUT

100

1.5

100

AV-IN 1

RGB

AV-IN 2

S-VIDEO

VIDEO

AUDIO

POWER

INPUT DC13V

163.9

30.5

229.4

65.5

LC-20B2EA

REMOVING OF MAJOR PARTS

1. Remove the two back covers.

2. Remove the table stand fixing screws (4 pcs.).

3. Remove the cabinet B fixing screws (14 pcs.) and detach the cabinet.

(3 : XBBSF30P06000, 3 : XEBSF40P16000)

4. Remove the reinforcement angle fixing screws (4 pcs.).

5. Detach the connector from each PWB.

Cabinet B

Back cover

Table stand

Back cover

Reinforcement angle

R/C Receiver PWB

Main PWB

Tuner PWB

Operation PWB

Inverter-A PWB

Inverter-B PWB

6. Remove the main PWB fixing screws (3 pcs.).

7. Remove the inverter-A PWB fixing screws (2 pcs.).

8. Remove the inverter-B PWB fixing screws (1 pc.).

9. Remove the chassis Frame-A fixing screws (3 pcs.).

10. Undo the hooks and slide the chassis frame B out of position. Take out the terminal PWB.

11. Remove the R/C receiver PWB fixing screws (2 pcs.).

12. Remove the operation PWB fixing screws (2pcs.).

13. Remove the 21-pin terminal fixing screw (2 pcs.).

LC-20B2EA

Chassis Frame-A

Main PWB

Tuner PWB

Inverter-A PWB

Inverter-B PWB

Operation PWB

R/C Receiver PWB

Chassis Frame-B

LC-20B2EA

» Precautions in handling the LCD panels

1. Work in a clean room (with humidities below 50%).

2. Be sure to wear an anti-static armband.

3. Handle the panels on an electroconductive mat.

4. Be careful not to fall, shake and shock the panels.

13.Remove the four screws and open the LCD display unit.

14.Detach the D-BEFM sheet, prism sheet, reflection sheet, ITO sheet and diffusion plate Cover.

15.Remove the Lamp-holder fixing screws (6 pcs.).

LCD Display Unit (Front)

Shielding Plate

Lamp Holder

Diffusion Plate Cover

Reflection Plate

Lamp Set-A

Lamp Set-B

Lamp Holder

LCD Display Unit

D-BEFM Sheet

Prism Sheet

Reflection Sheet

ITO Sheet

LC-20B2EA

» Precautions at the time of the side B(back) service of main unit.

1. Remove only SC2001 of the FFC for connection between Main unit(SC2001) and Tuner unit(SC3100), and connect the extended cable (QCNW-A369WJZZ) for service.

2. Remove only P3702 of the FFC for connection between Main unit(P3702) and Tuner unit(P1903), and connect the extended cable (QCNW-A371WJZZ) for service.

3. Remove only SC2002 of the FFC for connection between Main unit(SC2002) and Tuner unit(SC1602), and connect the extended cable (QCNW-A370WJZZ) for service.

4. Remove the R/C Receiver unit. 4-1. Peel off the tape. 4-2. Remove a lead from a wire holder. 4-3. Remove the R/C Receiver unit fixing screws(2 pcs.).

5. Remove the main unit fixing screws(3 pcs.), a substrate is reversed.

Main unit (Side B)

4-1

Tape

R/C Receiver PWB

Main PWB

SC2002

SC1602

P3702

SC2001

P1903

Tuner PWB

4-3

Wire holder

4-2

SC3100

LC-20B2EA

ADJUSTING PROCEDURE OF EACH SECTION

The best adjustment is made before shipping. If any position deviation is found or after part replace is performed, adjust as follows.

Preparation for adjustments

Use the dedicated AC adaptor or stable DC power supply. LC20E1E AC adaptor: UADP-0241CEPZ DC power supply: 13V 5.4A

1. Adjusting procedure

• Checker adjustment Power ON (Adjustment processing mode) → +B adjustment → Counter bias adjustment → TAMP (Contrast) adjustment → White balance adjustment

2. Entering the adjustment processing mode

There are the following two methods.

• Setting the pin (81)(KEY4) or pin (82)(KEY5) of IC2001 (microprocessor) to GND, turn on the power.

• A “POWER” key is made on with pushing an “TV/VIDEO” and “MENU” keys at the same time.(K of the inspection

process mode is displayed by the upper left of the image plane.) → Next, “CH (Ù)” and “VOL (–)” keys are pushed

at the same time.(It becomes the image plane of the adjustment process mode.).....When it is canceled, it is made

to turn it off.(Even off in the “MAIN POWER” key, off with R/C are good.)

3. Key operation in the adjustment process mode

• The receiving channel UP/DOWN is performed with the “CH (ù)/(Ù)” keys. One push ... The UP/DOWN tuning is performed per channel. Continuous push ... The UP/DOWN search is performed until a next receivable station is found.

• Various adjustments The adjustment is performed for each item by the “MENU”, “Menu cursor”, “CH (ù)/(Ù)” or “VOL (+)/(–)” keys (LCD TV set and remote control).

• Adjustment item is chosen with the Menu cursor upward/downward keys.

• The adjustment item makes a toggle operation with the “MENU” key input. (Next item) If the “MENU” key is input while the bottom item is selected, it moves to the top item on the next page.

• Press the auto preset button on the remote controller in the adjustment process mode, and the top item of the

next page will show up regardless of which item appears now. Page 1 → Page 2 → ... → Page 22 → Page 1

• Press the manual memory button on the remote controller in the adjustment process mode, and the top item of the same page will show up.

• UP/DOWN of each adjustment vale selected is performed with the VOL (+)/(–) keys input.

• For P16 – 17, the unit enters the register select mode with the VOL (+)/(–) keys input while NTSC/PAL is selected,

and the cursor moves to the address 01.

• The cursor moves up or down with the “CH (ù)/(Ù)” keys and moves left or right with the VOL (+)/(–) keys, and a decision is made with the 12 key. When the decision is made, the cursor moves to the adjustment value selected, and UP/DOWN of each adjustment value selected by the “VOL (+)/(–)” keys input is performed. 0 ↔ 1 ↔ ... ↔ 9 ↔ A ↔ ... ↔ F ↔ 0 ↔ ... Decide with the 12 key and return to the address select. Move to the next item with the “MENU” key. During address select, the cursor movement by the “VOL (+)/(–)” keys input is as follows: Example: 01 ↔ 02 ↔ 03 ↔ 01 ↔ ... The cursor movement by the “CH (ù)/(Ù)” keys input is as follows: Example: 02 ↔ 05 ↔ ... ↔ F6 ↔ 02 ↔ ...

LC-20B2EA

4. Initialization

When the microprocessor (IC2001) or the EEPROM (IC2004) has been replaced or when the EEPROM has been initialized, readjust the each adjustments. 4-1. Connect the pins (81) and (82) of IC2001 (microprocessor) to GND, and turn on the power. 4-2. Select the model name to (C2EA). 4-3. Select the inch size (20). 4-4. LED changes green from red after setting finish and about 15 seconds, initialization is completed, and it

becomes adjustment mode.

5. Adjustment

5-1. +B adjustment...Page 1 +B-ADJ

Adjust the voltage of the pin (13) of P2002 to 5.00 ±0.02V. Note: Since 5.0V is a reference voltage of all power voltage, adjust it precisely.

5-2. Counter-bias adjustment

Vary the "COM BIAS" setting on Page 2 of the adjustment process mode so that the contrast be sharpest (black looks most sinking).

5-3. TAMP adjustment

1) Receive the upper left of 75% white half colour bar signal.

2) See if the “Y” reading on page 2 of the adjusment process mode is somewhere following. If not, make the “PAL TAMP” adjustment to get the “Y” reading in the range of BF thru C9.

3) If the adjustment of “PAL TAMP” is executed, write its adjustment value to the “SECAM TAMP” manually.

(Screen of the page 2 of the adjustment processing menu OSD)

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

8 9

COM B I AS 2 0

PA L TAMP 2 7

SEC AM TAM P 2 7

RCU T OF F

GCU T O F F

BCU T OF F

G3 B3 R3 00 00 00

G1 B 4 Y 0 0 00 BE

TAMP H

TAMP L

Y Data

(White 75%)

–

– 1

5-4. White balance adjustment

Adjust “RCUTOFF” and “BCUTOFF” on the page 2 of the adjustment processing so as to obtain the colour of the same level as the standard set. Note: For the adjustment processing of “RCUTOFF” and “BCUTOFF”, adjust them in the indication value range of ... –9, –7, ... –1, +1, ... +7, +9. When it becomes even-numbered value, side favor noise sometimes occurs in the monochrome signal of the specific gradation.

LC-20B2EA

6. Factory Setting

6-1. Perform a factory setting after completing all adjustments. 6-2. A “POWER” keys is made on with pushing an “TV/VIDEO” and “MENU” keys at the same time. 6-3. “K” of the inspection process mode is displayed on the screen upper left. 6-4. CH (ù) and VOL (+) keys are pushed about 2 seconds at the same time. 6-5. Release keys, if “E” is displayed on the screen upper left and “COMPLETE” is displayed on the bottom of it. 6-6. After a while, a power will be in a standby mode and a setup will be finished. Note: “First installation” serves on “Deutsch”.

7. Lamp error detection

7-1. Functional description

This LCD colour television has a function (lamp error detection) to be turned OFF automatically for safety when the lamp or lamp circuit is abnormal. If the lamp or lamp circuit is abnormal, or some other errors happen, and the lamp error detection is executed, the followings occur. 1 The main unit of television is turned OFF 5 seconds after it is turned ON. (The power LED on the front side

of TV turns from green to red.)

2 If the situation 1 happens 5 times sequentially, television can not be turned ON. (The power LED remains

red.)

7-2. Countermeasures 7-2-1. Check when turning OFF the lamp error detection

When television is turned OFF by the lamp error detection mentioned above, it enters the adjustment process with the power LED red. Entering the adjustment process turns OFF the error detection and turns ON TV. This enables the operation check to detect errors in the lamp or lamp circuit. Check whether "ERROR NO RESET" on line 9, page 1 of the adjustment process is 1 or more. If it is 1 or more, it indicates the lamp error detection was executed.

7-2-2. Resetting of the lamp error count

After confirming that the lamp or lamp circuit is normal, reset the lamp error count. Select "ERROR NO RESET" on line 9, page 1 of the adjustment process and set the number to 0 using the volume button.

Page 1 of the adjustment process

+B– A D J 160

M O D E L C2EA INCH SIZE 20

NTSC PWM FREQ 0C0 PAL PWM FREQ 0BD NTSC PWM DUTY 0 PAL PWM DUTY 0 T V GAIN OFF ERROR N O RESET 5 PUBLIC MODE OFF

Reset 0

C2EA

Afterwards, perform the operation check to confirm that the lamp error detection does not function.

V E R 1 . 2 0 0

TROUBLE SHOOTING TABLE

No picture and No sound

Check all the settings microprocessor's adjust process menu.

Do F1 and F2 function?

Are T3701's secondary

outputs, +31V, +22V, +9V,

+5V and -8V normal?

Remove F1 and F2 and

check the load side.

Is there short-circuiting?

Is there short-circuiting of

T3701 primary side periphery,

Q3700, Q3701 and S4701.

Replace F1 and F2.

Check S4701 and

connection cable.

Is T3701's primary oscillator

waveform normal?

Check T3701's secondary

load.

Yes Yes

No No

Yes

Check J3702 periahery and

connection cable.

Replace F6700~F6704.

Is the pin (34) of IC1201 in

the "H" state?

Is the output of Q3650 in the

state?

Yes

Check the OFL1 line, IC1201

and their peripheral parts.

Check the OFL line, Q3650

and their peripheral parts.

Check T6700~T6709,

Q6700~Q6714 and

connection cable.

Back light lamp failure to light up

Is the primary side of

T6700 ~T6709 periphery

short-circuiting?

Replace the back light lamp

with new one and check

again.

LC-20B2EA

No picture (1/3)

Check all the settings microprocessor's adjust process menu.

Is in/output of

IC801 normal?

Is in/output of

IC1201 normal?

Check IC801

and its

peripheral parts.

Check IC1201

and its

peripheral parts.

Check IC402

and its

peripheral parts.

Check IC801,

AV1 line and its

peripheral parts.

Check LCD

panel voltages

and waveform.

Yes

No picture

at all

Is in/output of

IC402 normal?

Is input at pin

(73) of IC801

normal?

Yes

No TV and

S-Video

output

Is voltages at

pins (6), (7) and

(18) of tuner

normal?

Is output at pin

(13) of tuner

normal?

Check their

power line.

Check tuner

and its

peripheral parts.

Is input at pin

(3) of tuner

normal?

Is the pins (2)

and (4) of IC402

at "H" and "L"

state?

Yes

No TV output

Is the pins (65)

and (66) of

IC2001 at "H"

and "L" state?

Yes

Check the its

line.

Check the its

line.

Check IC402

and its

peripheral parts.

Is input at pin

(75) of IC801

normal?

Check V1 IN

line and its

peripheral parts.

No VIDEO 2

output

Check the SY-line,

SC-line and their

peripheral parts.

Is input at pin (1)

of IC402 and pin

(71) of IC801

normal?

No S-VIDEO

output

TROUBLE SHOOTING TABLE (Continued)

No picture (2/3)

Check all the settings microprocessor's adjust process menu.

Is input at pin

(74) of IC801

normal?

Check the AV2

line and its

peripheral parts.

No VIDEO 1

output

Check IC1203

and its

peripheral parts.

Yes

No TELETEXT

output

Yes

Is input at pins (2),

(5), (11), and (14)

of IC1203 normal?

Is input at pins (3),

(4) and (5) of

SC1602 normal?

Is output at pins (1)

and (7) of IC1619 and

pin (1) of IC1620

normal?

Check connection

cable

Check the R, G

and B line.

Check IC1619,

IC1620 and their

peripheral parts.

Is output at pins

(57)~(59) of IC1601

normal?

Yes

Check V2VO line

and its peripheral

parts.

Is input at pin (21) of

IC1601 normal?

Check IC1601 and its

peripheral parts.

Is output of

R0~R7

normal?

Is output of

G0~G7

normal?

Is output of

B0~B7

normal?

Yes

Colour is

unusual

Check R1202 and

its peripheral parts.

Check R1203 and

its peripheral parts.

Check R1204 and

its peripheral parts.

Is in/output of

SPIO and

SPOI normal?

No picture

image

inversion

Gradation

defect

Is output of U/D

normal?

Check R1209 and

its peripheral parts.

Check IC1206,

IC1207, Q1201 and

their peripheral parts.

Is output V0, V7, V17,

V21, V32, V64, V122,

V176, V235 and

V255 normal?

Check IC1106,

IC1107, IC1108,

IC1114, IC1115 and

their peripheral parts.

TROUBLE SHOOTING TABLE (Continued)

LC-20B2EA

No sound (1/2)

Check all the settins microprocessor's adjust process menu.

Is the pin (53) of

IC2001 in the

"L" state?

Is output at pins

(27) and (28) of

IC1901 normal?

Is output at pins

(1) and (7) of

IC1903 normal?

Yes

No sound

from front

speakers

Yes

Muting effect is

on. Check the

FSMUTE line.

Check IC1901

and its

peripheral parts.

Check IC1903

and its

peripheral parts.

Is the pin (52) of

IC2001 in the

"L" state?

Is output at pins

(24) and (25) of

IC1901 normal?

Is output at pins

(1) and (7) of

IC304 normal?

Yes

Muting effect is

on. Check the

HP_MUTE line.

Check IC1901

and its

peripheral parts.

Check IC304

and its

peripheral parts.

No sound

from

headphone

TV sound

failure

Is output at pins

(33) and (34) of

IC1901 normal?

Is output at pins

(1) and (7) of

IC3500 normal?

Check IC1901

and its

peripheral parts.

Check IC3500

and its

peripheral parts.

Yes

No sound

from output

line

Check the tuner

and its

peripheral parts.

Yes

Is output at pin

(11) of Tuner

normal?

Is input at pins

(67) and (69)

of IC1901.

Check IC1901

and its

peripheral

parts.

Check

Headphone Jack

and connection

cable.

Is output at pins

(8) and (12) of

IC3305 normal?

Check IC3305

and its

peripheral parts.

Check front

speaker and

connection

cable.

Yes

TROUBLE SHOOTING TABLE (Continued)

No sound (2/2)

Check all the settings microprocessor's adjust process menu.

Yes

No sound from SCART

SCART sound failure

Yes

Check IC1901 and its

peripheral parts.

Is output at pins (36) and (37) of

IC1901 normal?

Check IC1902 and its

peripheral parts.

Is output at pins (1) and (7) of

IC1902 normal?

Check their lines and their

peripheral parts.

Is input at pins (53) and (54) of

IC1901 normal?

Check IC1901 and its

peripheral parts.

Is output at pins (27) and (28) of

IC1901 normal?

TROUBLE SHOOTING TABLE (Continued)

LC-20B2EA

CHASSIS LAYOUT

OPERATION Unit

MAIN Unit

TERMINAL Unit

R/C RECEIVER Unit

87109654321

INVERTER-A Unit

LC-20B2EA

INVERTER-B Unit

1716 1918151413121110

LC-20B2EA

BLOCK DIAGRAM

V1.SY

TUNER

TV_V

SIF1/2

AI_L/R

SC_L/R

TV/AV

SELECTOR

IC402

AUDIO AMP

IC1902

ANA_IN1+/2+

SC2_IN_L/R

SC1_OUT_L/R

SC1_IN_L/R

V2_V R/G/B_IN

V1. SC

V1IN

DACM_L/R

MSP

IC1901 DACA_L/R

VPC

IC801

PROM

IC2030

CSYNC

SPI

V2VO

SYNC SEP

IC401

UART

SC2_OUT_L

MICON IC2001

ANTENNA

SC3903

SCART (AV1)

AUDIO IN

AUDIO OUT

VIDEO OUT

SDA/RXD

SCL/TXD

C/UART

VIDEO IN

SC5001

R/G/B_ST

INPUT

J5002

VIDEO (AV2)

INPUT

J5001

AUDIO (AV2)

V1.L/R

INPUT

J3702

DC13V

REG

IC1208

+3.3V

INPUT

+5V

Q3704

+22V

PAVCC

REG

IC751

IC703

IC3702

DC/DC

CONVERTER

SIGVCC

T3701

+31V

–20V

Q3706

Q3707

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REG

IC752

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–8V

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PWM

INVVCC

Q3700

IC3701

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REG

IC1610

REG

IC1606

IC1613

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