Sharp LC-20SH21U Schematic

SERVICE MANUAL

In the interests of user

safety (Required by safety regulations in some countries) the set should be

SHARP CORPORATION

Contents

LCD COLOR TELEVISION

MODEL LC-20SH21U

LC-20SH21U

restored to its original condition and only parts identical to those specified should be used.

1. Precautions and Safety Notices………………………….……………….…….2

2. Specifications………………….………………………….……………….….…..5

3. Servicing Environment………………………………….…………………....….6

4. Disassembly of Major Parts……….…….………………………..……….…....7

5. Wiring Diagram……………………..………………………….…………..……12

6. Block Diagram…………………….……………………………..………...…….13

7. Alignment Procedure For White Balance……….…………………..………...14

8. Firmware Upgrade Procedure ……….………………...……………………...22

9. Troubleshooting A nalysis………….…………….…………….………….…....23

10. Exploded View ……………………………………….………………………..…27

11. Part List………………………………………………………………….…..........29

Page

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

LC-20SH21U

1. Precautions and Safety Notices

Prior to using this manual, please ensure that you have carefully followed all the procedures outlined in the user manual for this product.

l Read all of these instructions. l Save this instructions for later use l Follow all warnings and instructions marked on the product. l Do not use this product near water. l This display should be installed on a solid horizontal base. l When cleaning, use only a neutral detergent cleaner with a soft damp cloth. Do not spray with

l Do not expose this display to direct sunlight or heat. Hot air may cause damage to the cabinet l Adequate ventilation must be maintained to ensure reliable and continued operation and to

l Do not allow metal pieces or objects of any kind fall into the display from ventilation holes.

Slots and openings in cabinet and the back or bottom are provided for ventilation. To ensure reliable operation of the product and to protect it from overheating, these openings must not be blocked or covered. The openings should never be blocked by placing the product on a bed, sofa, rug, or other similar surface. This product should not be plac ed near or over a radiator or heat register. This product should not be placed in built-installation unless proper ventilation is provided.

liquid aerosol cleaners. and other parts. protect the display from overheating. Do not block ventilation slots and openings with objects

or install the display in a place where ventilation may be hindered.

LC-20SH21U

Safety Guidelines

CAUTION: The power supply outlet should be located near the HD TV and should be easily

accessible. Always use the appropriate AC cord that is certified for your specific country. Some examples are listed below:

USA..................UL Switzerland ..... SEV

Canada.............CSA Britain ............. BASE/BS

Germany..........VDE Japan ............... Electric Appliance Control Act

IMPORTANT NOTICE CONCERNING POWER CORD SELECTION

The specific power cord for this HD TV is enclosed and has been selected according to the country of destination and must be used to prevent electric shock. Use the following guidelines if it is necessary to replace the original cord set, or if the cord set is not enclosed. The female receptacle of the cord set must meet IEC-60320 requirements and should look like Figure A1 below:

Figure A1 Figure A2

For the United States and Canada

In the United States and Canada the male plug is a NEMA5-15 style (Figure A2), UL Listed, and CSA Labeled. For LCD TVs that are placed on a desk or table, type SVT or SJT cord sets may be used. For LCD TVs placed directly on the floor, only SJT type cord sets may be used. The cord set must be selected according to the current rating for the LCD TV. Please consult the table below for the selection criteria for power cords used in the United States and Canada.

Cord Type Size of Conductors in Cord Maximum Current Rating of Unit

SJT

SVT

18 AWG 16 AWG 14 AWG 18 AWG 17 AWG

10 Amps 12 Amps 12 Amps 10 Amps 12 Amps

LC-20SH21U

FCC Compliance Statement

This equipment has been tested and complies 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 in a residential installation. This equipment generates, uses, and can radiate radio frequency energy, and may cause harmful interference to radio communications if not installed and used in accordance with the instructions. 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 user is encouraged to try to correct the interference by one or more of the following measures:

FCC Warning

To assure continued FCC compliance, the user must use a grounded power supply cord and the provided shielded video interface cable with bonded ferrite cores. If a BNC cable is used, use only a shielded BNC (5) cable. Also, any unauthorized changes or modifications not expressly approved by SHARP CORPO RATION will void the user's authority to operate this device.

• Reorient or relocate the receiving antenna.

• Increase the separation between the LCD TV and receiver.

• Connect the equipment into an outlet on a circuit different from that to which the receiver is

connected.

• Consult the SHARP Service Center or an experienced radio/TV technician for assistance.

LC-20SH21U

2. Specifications

Model Name LC-20SH21U Panel Type

Viewing Angles 160° (H) / 140° (V) Input Signal Video/Audio VGA Analog * 1 (75 ohms, 0.7 Vp-p)/Mini-Stereo *1

H/V separated (TTL) for PC; fh: 30-48 kHz, fv: 50-75 Hz HDMI-HDCP *1 / RCA (L/R) stereo *1 TV system antenna / NTSC & ATSC *1 in USA(F type)

YPbPr * 1 / RCA (L/R) Stereo * 1

AV2 * 1 / RCA (L/R) Stereo * 1 Composite * 1 / S–Video * 1 / RCA (L/R) stereo * 1

Output Signal RCA (L/R) Stereo * 1;SPDIF (PCM/RAW) *1 HDTV Compatibility 480i, 480P, 720P, 1080i

The best TVs use the best technology: ATI inside your TV for The Ultimate Visual

Video Engine

PC Compatible Recommended 1360 x 768@60Hz(reduce blanking)

H = 30~48KHz V= 50~75 Hz

Experience.™ Your new Sharp TV is powered by ATI’s Xilleon™ image processing chip for the true high definition cinematic experience. Enjoy your new Sharp TV with ATI inside.

20" (20" viewable diagonal area), TFT (Thin Film Transistor), TN model, 1366 x 768 Normally White

1280 x 720@60Hz 720 x 400 1024 x 768@60Hz 640 x 480

Speaker Output 2.5w (x 2 Channels) Power Voltage 120VAC, 60 Hz, 1.5A Temperature Operating 0 to + 35° C (Hum. <90%) (Note A) Storage -20 to +60 oC (Hum.< 35 %) Humidity (Relative) Operating 20 to 90% no n-condensing. (Ta< 35%) (Note A) Storage 10 to 90% non-condensing. (Note A)

Wet-bulb temperature should be 39 oC Max. (Ta> 40oC) Note A: The temperature and relative humidity range is shown in right side

Altitude Operating 0 to 3,000 m Storage 0 to 12,000m Dimensions Physical 509 mm (W) x 408 mm (H) x 203 mm (D) Weight Net / Gross 6.4 kg / 8.3 kg Regulations UL/C-UL, FCC-B, UL(UL60065) / C-UL,ICES-003,BETS-T

Consumption (DC Power)

Preset Timing Mode:

Selects timing mode at 1360 x 768 / 60 Hz (reduce blanking) or recommended timing, when you set the graphics card in your computer. Note: Product Specifications are subject to change without notice.

On DC OFF Power saving

70w (Blue LED)

0.5w (LED off) 14w (Amber LED)

LC-20SH21U

3. Servicing Environment

1. This LCD TV should be used only with the power source type identified on the package and

2. Service the LCD TV in a room with low humidity and free of dust.

3. Place the LCD TV on a firm, level surface. Subjecting the LCD TV to a drop or sharp impact

4. If necessary, clean the LCD TV with a slightly damp cloth using clean water.

5. In the event that the powered LCD rapidly heats, or emits unusual smells or noises,

6. To avoid electrical hazard, make sure that the LCD TV is fully assembly the casing closed, and

7. Internal components of LCD display may be damaged by electrostatic discharge(ESD). Carry

8. Before opening the housing, disconnect the product from all power source and remove any

User’s Guide

may cause severe damage to thin glass, plastic surface materials, and internal components. Disconnect the LCD TV fro m the power source before cleaning. DO NOT use ammonia -based

cleaning products. immediately disconnect the LCD TV From the power source. the screws tightened completely before plugging in LCD TV for testing. out repairs in an ESD-protected work shop. If no such workshop is available, wear an

antistatic wrist strap or touch a highly conductive metal object.

connecting cable. If the display has not been disconnected from the power outlet before being opened, there is a danger to life through electric shock. These is also a risk of damage to the components