Viewsonic VG170M-1 Service Manual 1b

Model No. VLCDS23724-3W

17” Color TFT LCD Display

Service Manual

ViewSonic VG170m

ViewSonic



381 Brea Canyon Road, Walnut, California 91789 USA - [phone]

(VG170m-1_SM_625 Rev. 1a – Jan.2004)

Copyright

Copyright

¤

2003 by ViewSonic Corporation. All rights reserved. No part of this publication may be

reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language or

computer language, in any form or by any means, electronic, mechanical, magnetic, optical, chemical,

manual or otherwise, without the prior written permission of ViewSonic Corporation.

Disclaimer

ViewSonic makes no representations or warranties, either expressed or implied, with respect to the

contents hereof and specifically disclaims any warranty of merchantability or fitness for any particular

purpose. Further, ViewSonic reserves the right to revise this publication and to make changes from time

to time in the contents hereof without obligation of ViewSonic to notify any person of such revision or

changes.

Revision History

Revision Date Description Of Changes Approval

Trademarks

ViewSonic is a registered trademark of ViewSonic Corporation.

All other trademarks used within this document are the property of their respective owners.

Optiquest is a registered trademark of ViewSonic Corporation.

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i

1b 07/01/04 Revise DCN- 3755 Angela Luh

1a 11/05/02 Initial Release DCN- 2776 C Shen

TABLE OF CONTENTS

2. Specification

3. Front Panel Function Control Description

4. Circuit Description

6. Trouble Shooting Flow Chart

9. Block Diagram

10. Schematic Diagrams

7. Recommended Spare Parts List

1. Precautions and Safety Notices

5. Adjusting Procedure

8. Exploded Diagram And Spare Parts List

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11. PCB Layout Diagrams

1

2

4

5

6

7

12

16

19

20

22

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.

Read all of these instructions.

Save these instructions for later use.

Follow all warnings and instructions marked on the product.

Do not use this product near water.

This display should be installed on a solid horizontal base.

When cleaning, use only a neutral detergent cleaner with a soft damp cloth. Do not spray with liquid or aerosol cleaners.

Do not expose this display to direct sunlight or heat. Hot air may cause damage to the cabinet and other parts.

Adequate ventilation must be maintained to ensure reliable and continued operation and to 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.

Do not install this display near a motor or transformer where strong magnetism is generated. Images on the display will

become distorted and the color irregular.

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

Slots and openings in the cabinet and the back or bottom are provided for ventilation, to ensure reliable operation of the

product and to protect it from overheating, those openings muse 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 never be placed near or over

a radiator or heat register. This product should not be placed in a built-in installation unless proper ventilation is provided.

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2. Specification

2.1. PRODUCT SPECIFICATIONS

LCD panel type

17.0

”

TFT(AU)

Power Consumption

40 W

Displayable Resolution

SXGA 1280 x 1024 maximum

Pixel dimension

0.264 mm x 0.264 mm

Display Color

16.7 M

Viewing Angle

(CR≥10)

Horizontal: ±70

°

Vertical: ±70

°

Response Time

Tr:12ms Tf:4ms( typ).

Contrast Ratio

450:1 typ.

Brightness

200 cd/m

2

(min),260 cd / m

2

typ.

Active Display Area

337.9 mm horizontal x 270.3mm vertical

AC/DC adapter

Input:AC 100~264V,47~63 Hz

Output:+12V DC.

Dimensions ( WxHxD )

415 mm(W) x 403(H) mm x 229(D) mm

Weight (Net / Gross)

5.4/7.6 kg (unit)

Input connector

15 Pin D-Sub.

Power management

YES

Temperature

Operating : 0

°

C ~ +40

°

C

Storage : -20

°

C ~ +60

°

C

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2.2. FACTORY SUPPORTING MODES

Primary Preset VESA 1280 x 1024 @ 60 Hz

Factory Preset Modes

1. VESA 640 x 350 @ 70Hz, 31.47kHz, -/+

2. VESA 720 x 400 @ 70Hz, 31.467kHz, +/-

3. VESA 640 x 480 @ 60Hz, 31.469kHz, -/-

4. VESA 640 x 480 @ 72Hz, 37.861kHz, -/-

5. VESA 640 x 480 @ 75Hz, 37.5kHz, -/-

6. MAC 640 x 480 @ 67Hz, 35kHz,

7. VESA 800 x 600 @ 56Hz, 35.156kHz, +/+

8. VESA 800 x 600 @ 60Hz, 37.879kHz, +/+

9. VESA 800 x 600@ 72Hz, 48.077kHz,+/+

10. VESA 800 x 600 @ 75Hz, 46.875kHz, +/+

11. MAC 832 x 624 @ 75Hz, 49.725kHz,

12. VESA1024 x 768 @ 60Hz, 48.363kHz, -/-

13. VESA1024 x 768 @ 70Hz,56.476kHz, -/-

14. VESA 1024 x 768 @ 72Hz, 58.036kHz, -/-

15. VESA 1024 x 768 @ 75Hz, 60.023kHz, +/+

16. MAC 1024 x 768 @ 75Hz, 60.241kHz,

17. VESA 1280 x 1024 @ 60Hz, 63.981kHz, +/+

18. VESA 1280 x 1024 @ 75Hz, 79.976kHz, +/+

19. MAC 1152 x 870 @ 75Hz, 68.6kHz,

2.3. D-SUB CONNECTOR

This section describes the pin assignment of the LCD’s video connector. It is called 15 Pin Mini D-sub Connector.

Pin NO.

Signal Connector

1

Red Video Signal

2

Green Video Signal

3

Blue Video Signal

4

N.C.

5

Ground

6

Ground

7

Ground

8

Ground

9

+5v

10

Ground

11

N.C.

12

DDC data

13

Horizontal sync signal

14

Vertical sync signal

15

DDC clock

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3. Front Panel Function Control Description

Location of Controls

MUNT [1]MENU ADJUST

▲ LED POWER

;

-VOL

-

[2]ENTER

;

+ VOL+ ADJUST

▼

1) POWER :

Press the power button to turn the monitor on. Press it again to turn the monitor off.

2) [1]MENU :

Enter or exit the OSD adjustment menu.it also exit from the submenu back to previous menu.

3) [2]ENTER :

To confirm the current selection

4) ADJUST

▲

(UP)

To scroll up in menu or to increase value of selected item.

5) ADJUST

▼

:(DOWN)

To scroll down in menu or to decrease value of selected item.

6) MUNT: Temporarily silences audio output.

7)

;

-VOL -: Decreases or increase volume.

8)

;

+ VOL+: Decreases or increase volume.

9) POWER INDICATOR :

The LED will light with green color in normal on state,and will light with orange color in power saving mode.

10) Brightness/Contrast: press button UP/DOWN .

11) Auto Image Adjust : press button [2] .

12) OSD lock and unlock: press two buttons [1]&[up] simultaneously for 10 seconds.

13) Power lock and unlock: press two buttons [1]&[Down] simultaneously for 10 seconds.

14) ALL RESET: First, power off the monitor, un-plug the AC cord, then press “

▲

” and “Power “ key at the same

time and plug the AC cord.

15) Factory Mode:First, power off the monitor, un-plug the AC cord and be sure the signal cable is connected(D-sub

connected) , then press “2” and “Power “ key at the same time and plug the AC cord.

16) RUN-IN mode: First, power off the monitor, un-plug the AC cord and be sure the signal cable is not connected (D-sub

not connected) , then press “2” and “Power “ key at the same time and plug the AC cord.

17) ISP mode:First, power off the monitor, unplug the AC cord, then press “2” and “Power “ and “down” key at the same

time and plug the AC cord.

18) AUTO color: then press “1” and “▲“ and “▼” key at the same time

.

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4 Circuit Description

A. DC-DC CONVERTER AND LDO

This brick converts the 12V input voltage to 5V for panel use and U9 converts the voltage from 5V to 3.3V ,U8 converts

the voltage from 5V to 2.5V for controller use.

It consists of a PWM IC (LM2596), flywheel Diode (D4), buck choke (L1), and capacitor (C68,C69).

U7 (LM2596) is a PWM generator working at 150Khz.

Self protection features include a two stage frequency reducing current limit for the output switch and an over temperature

shutdown for complete protection under fault condition.

U8 is a low dropout voltage and fast trasient response three terminal regulator, the output voltage is 2.5V fixed.

U9 is a low dropout voltage and fast trasient response three terminal regulator, the output voltage is 3.3V fixed.

B. Scaling controller

The gm2121 is a graphics processing IC for Liquid Crystal Display (LCD) monitor at SXGA resolution . It provides a

high-speed triple-ADC and PLL,a high quality zoom and shrink scaling engine , an on-screen display (OSD) controller,

digital color controls, an on-chip micro-controller ( OCM ) and industry standard dual four channel LVDS transmitter for

direct connect to LCD panel with LVDS interface.

The triple-ADC is to convert RGB analog signal to digital signal. The gm2121 is a complete 8-bit up to 162MHz

(SXGA 75Hz / UXGA 60Hz) monolithic analog interface optimized for capturing RGB graphic signal, +3.3V and +2.5V

power supply is necessary.

The gm2121 scaling filter can combine it’s advanced scaling with a pixel-replication type scaling function.this is useful for

improving the sharpness and definition of graphics when scaling at high zoom factors. Gm2121 provides an 8 to 10 bit

look-up table (LUT) for each input color channel intended for Gamma correction and to compensate for a non-linear

response of the LCD panel . A 10-bit output results in an improved color depth control. The 10-bit output is then dithered

down to 8 bits( or 6 bits) per channel at the display .

C. AMP

The APA4835 is a monolithic integrated circuit , which provides DC volume control , and a stereo bridged audio power

amplifiers capable of producing 2W (2.2W) into 4Ω with less than 10% (1.0%) THD+N. APA4835 includes a DC volume

control , stereo bridge-tied and single-ended audio power amplifiers , stereo docking outputs , and a selectable gain control,

that makes it optimally fittable for notebook PC, multimedia monitors , and other portable applications.

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5. Adjusting Procedure

First, power off the

monitor, un-plug the AC cord and be sure the signal cable is connected(D-sub connected),

then press “2” and “Power “ key at the same time and plug the AC cord to factory.

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