ViewSonic E55-2 User manual

Service Manual
ViewSonic E55-2
Model No. VCDTS21914-2
15” Digital Controlled Color Monitor
(E55-2_SM_566 - Rev. 1a – May 2002)
ViewSonic381 Brea Canyon Road, Walnut, California 91789 USA - [phone]

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Copyright
Copyright
¤
2002 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.
Trademarks
ViewSonic is a registered trademark of ViewSonic Corporation.
All other trademarks used within this document are the property of their respective owners.
Revision History
Revision Date Description Of Changes Approval
1a 7/15/02 Initial Release DCN-2342 K.Yang
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TABLE OF CONTENTS
1. PRECAUTIONS AND NOTICES...............................................................................1
2. SPECIFICATIONS.....................................................................................................3
3. TIMING CHART......................................................................................................5
4. FRONT PANEL FUNCTION CONTROL DESCRIPTION..........................................6
5. ADJUSTING PROCEDURE.......................................................................................8
6. CIRCUIT DESCRIPTION.........................................................................................11
7. TROUBLE SHOOTING FLOW CHART..................................................................22
8. BLOCK DIAGRAM..................................................................................................26
9.EXPLODED DIAGRAM AND SPARE PARTS LIST...............................................27
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10.RECOMMEND SPARE PARTS LIST......................................................................29
11.SCHEMATIC DIAGRAMS.......................................................................................31
12.PCB LAYOUT DIAGRAM.......................................................................................35
E55-2

!
WARNING !
This service information is designed for experiencedrepair technicians only and is not designed for use by the
general public.
It does not contain warning or caution to advise non-technical individuals of potential dangers in attempting
to service a product. Product powered by electrical should be serviced or repaired only by experienced
professional technicians. Any attempt to service or repair the products dealt within this service information
by anyone lese could result in serious Injury or death.
1. CAUTION.
No modification of any circuit should be attempted. Service work should only be performed
after you are thoroughly familiar with all of the following safety checks and servicing guide
lines.
2. SAFETY CHECK.
Care should be taken while servicing this CRT display because of the high voltage used in the
defection circuits. These voltages are exposed in such areas as the associated flyback and yoke
circuits.
3. FIRE & SHOCK HAZARD.
Insert an isolation transformer between the CRT display and AC power line before servicing the
chassis. In servicing,pay attention to original lead dress especially in the high voltage circuit. If a
short circuit is found, replace all parts which have been overheated as a result of the short circuit.
All the protective devices must be reinstalled per original design.
Soldering must be inspected for possible cold solder joints, frayed leads, damage insulation, solder
splashes or sharp solder points. Be certain to remove all foreign material.
4. LEAKAGE CURRENT COLD CHECK.
Unplug the AC cord and connect a jumper between the prongs on the plug.
Turn the CRT display power switch “on”
Measurement the resistance value with an ohmmeter between the jumpered AC plug and each exposed
metallic part on the CRT display such as the metal frame, screwheads, control shafts, etc. When the
exposed metallic part has a return path to the chassis, the reading should be 1.8 MegaOhm minimum.
5. LEAKAGE CURRENT HOT CHECK.
Plug the AC cord directly into the AC outlet. Do not use and isolatetransformer during this check.
Connect a 1500ohm, 10 watt resistor, paralleled by a 0.15uF capacitor between each exposed metallic
part and a good earth ground (as shown in Fig.1)
Use an AC voltmeter with 1000ohm/volt or more sensitivity and measure the AC voltage across the
combination 1500ohm resistor and 0.15uF capacitor.
5-1 Move the resistor connection to each exposed metallic part and measure the voltage.
5-2 Reverse the polarity of the AC plug in the AC outlet and repeat the above measurement.
5-3 Voltage measured must not exceed 7.5 volt RMS, from any exposed metallic part to ground A
leakage current tester may be used the above hot check, in which case any current measured
1. PRECAUTIONS AND NOTICES
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must not exceed 5.0 milliamp. In the case of a measurement exceeding the 5.0 milliamp value,
a rework is required to eliminate the chance of shock hazard.
Note: High voltage is present when this CRT display is operating. Always discharge the anode of the
picture tube to the display chassis.
6. IMPLOSION PROTECTION.
Picture tubes are equipped with an integral implosion protection system, but care should be taken to
avoid damage and scratching during installation.
7. X-RADIATION.
WARNING: The only potential source of X-Radiation is the picture tube. However when the high
voltage circuit is operating properly there is no possibility of X-Radiation problem, The basic
precaution which must be exercised is to keep the high voltage at the following factory-recommened
level.
Note: It is important to use an accurate periodically calibrated high voltage meter.
7-1 The procedure for adjusting high voltage is shown on page 49.
7-2 If high voltage cannot be set to 26KV, immediate service is required the possibility of premature
component failure.
7-3 To prevent X-Radiation possibility,it is essential to use specified picture tube.
IMPORTANT SAFETY NOTICE
There are special component used in this CRT displays
Which are important for safety. These parts are identified
By the international symbol on the schematic
Diagram and on the replacement parts list. It is essential
that theses circuit parts should be replaced with
Manufacture’s specified parts to prevent X-RADIATION,
Shock fire, or other hazards. Do not modify the original
design or this will void the original parts and labor
guarantee.
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1Input requirements
1.1 AC power supply
1.1.1 Power source 90~264VAC 50/60Hz
1.1.2 Power consumption Less than 75W
1.1.3 Inrush current Less than 30Ap-p for 1/2 cycle at 110V, less than
60Ap for 1/2 cycle at 240V on cold starting
1.1.4 Input current 1.2 A Max in 110V
1.1.5 Leakage current 0.25mA at AC 110V
1.1.6 Ripple / noise Should not cause any visible interference
1.1.7 Power cord 1.8 meter, Ivory
1.2 Video interface
1.2.1 RGB video Analog 0.7Vp-p positive
input impedance 75 OHM
1.2.2 Max PC video signal 950mV with no damage to monitor
1.2.3 Max MAC video signal 1250mV with no damage to monitor
1.2.4 Sync signal Separate or composite horizontal and
vertical sync TTL level
1.2.5 Signal memory modes 10 preset modes, 10 user modes (See detail page7)
1.2.6 Plug & play VESA DDC1 / 2B
1.3 Scanning frequency
1.3.1 Horizontal 30KHz to 70KHz
1.3.2 Vertical 50Hz to 160Hz
2. CRT specifications.
ITEM SPEC
Size 15”
Diagonal 13.82”
Deflection
90q
Persistence P22 medium short persistence phosphor
Phosphor pitch 0.28mm
Mask type Anti doming Invar mask mask
Screen finish Anti-glare, anti-static
Face plate Filter glass
CRT TOSHIBA CRT : M36LGE23X205
2.SPECIFICATIONS
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3.Power saving
4. Picture display size.
Horizontal size 270 + 4mm
Vertical size 202 + 4mm.
5. Color temperature: Using the CIE color temperature coordinate system.
5.1 Chrominance Color 9300oK: x = 0.283+0.020
y = 0.297+0.020
Color6500
oK: x = 0.313+0.020
y = 0.329+0.020
5.2 Luminance (Light output) in 60 KHz 1024*768 mode
5.2.1 High light : At 70mm x 70mm white pattern , Brightness 50% ,
Contrast 100% : Y = 46 + 4 FL
5.2.2 ABL : At full-white pattern , Brightness 50% , Contrast 100% : Y = 30+2FL.
5.3.3 Low light : At Dark pattern Brightness 100% Contrast 0 % :Y = 0.3~1.3 FL
6. Physical specifications.
Monitor dimension.
Height : 368 mm Width : 365mm Depth : 394mm Monitor weight : 12.5 Kg.
Carton dimension.
Height : 455 mm Width : 448 mm. Depth : 483 mm. Gross weight : 14.5 Kg.
7. Environmental conditions.
7.1 Temperature and humidity at operation : 0 ~ 40 °C and
5% ~ 95% RH㧔without condensation㧕.
7.2 Temperature and humidity at storage : -40 ~ 60 °C and
5 ~ 95% RH Less than 6 month.
7.3 Altitude: Operating : 0 ~ +3000 metres ( ~ 10000 feet ).
Non-operating : 0 ~ +12000 metres ( ~ 36000 feet ).
Status Horizontal Sync. Vertical Sync. Power consumption Power LED
Normal Yes Yes <75W Green
Power saving No Yes < 5 W Amber
Power saving Yes No < 5 W Amber
Power saving No No < 5 W Amber
Over range 10~29 ±1kHz or
>71 ±1kHz
10~49 ±1Hz or
>160.5 ±1.5Hz < 5 W Amber
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MODE NO. 1 2 3 4 5 6 7 8 9 10
VGA VGA VESA VESA VESA VESA VESA VESA MAC MAC
MODE NAME 640X 640X 640X 800X 800X 1024X 1024X 1280X 640X 832X
400 480 480 600 600 768 768 1024 480 624
HORIZONTAL DOTS 640 640 640 800 800 1024 1024 1280 640 832
VERTICAL LINES 400 480 480 600 600 768 768 1024 480 624
PIXEL CLOCK (MHZ) 25.175 25.175 31.500 49.500 56.250 78.750 94.500 108.000 30.240 57.270
HORIZONTAL FREQ
(KHZ) 31.470 31.470 37.50 46.875 53.674 60.023 68.677 63.981 35.000 49.717
SYNC. POLARITY - - - + + + + + - -
A H.TOTAL (us) 31.778 31.778 26.667 21.333 18.631 16.660 14.561 15.630 28.571 20.115
(PIXELS) (800) (800) (840) (1056) (1048) (1312) (1376) (1688) (864) (1152)
B H.SYNC (us) 3.813 3.813 2.032 1.616 1.138 1.219 1.016 1.037 2.116 1.118
(PIXELS) (96) (96) (64) (80) (64) (96) (96) (112) (64) (64)
C H.BACK PORCH (us) 1.907 1.907 3.810 3.232 2.702 2.235 2.201 2.296 3.715 3.911
(PIXELS) (48) (48) (120) (160) (152) (176) (208) (248) (96) (224)
D H.ACTIVE (us) 25.422 25.423 20.317 16.162 14.222 13.003 10.836 11.852 21.164 14.528
(PIXELS) (640) (640) (640) (800) (800) (1024) (1024) (1280) (640) (832)
E H.FRONT PORCH 0.636 0.636 0.508 0.323 0.569 0.203 0.508 0.444 2.116 0.558
(PIXELS) (16) (16) (16) (16) (32) (16) (48) (48) (64) (32)
VERTICAL FREQ (HZ) 70.080 59.940 75.00 75.000 85.000 75.029 85.000 60.200 66.667 74.530
SYNC POLARITY + - - + + + + + - -
OV. TOTAL (ms) 14.268 16.648 13.333 13.333 11.756 13.328 11.765 16.661 15.000 13.417
(LINES) (449) (525) (500) (625) (631) (800) (808) (1066) (525) (667)
PV. SYNC (ms) 0.064 0.064 0.080 0.064 0.056 0.05 0.044 0.047 0.086 0.060
(LINES) (2) (2) (3) (3) (3) (3) (3) (3) (3) (3)
Q V.BACK PORCH (ms) 1.112 1.049 0.427 0.448 0.053 0.466 0.524 0.594 1.114 0.784
(LINES) (35) (33) (16) (21) (27) (28) (36) (38) (39) (39)
R V.ACTIVE (ms) 12.711 15.254 12.800 12.800 11.179 12.795 11.183 16.005 13.714 12.552
(LINES) (400) (480) (480) (600) (600) (768) (768) (1024) (480) (624)
S V.FRONT PORCH (ms) 0.381 0.381 0.027 0.021 0.019 0.017 0.015 0.016 0.086 0.021
(LINES) (12) (10) (1) (1) (1) (1) (1) (1) (3) (1)
3.TIMING CHART
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Key function define
1 2 Power switch
( Pressing key)
Normal key function
12PPower Switch
12 P
Adjust to increase value and move up the cursor
12 P
Adjust to decrease value and move down the menu
1 2 P To select the main menu and move sub-menu curser.
12 P
To display OSD menu
12 P
Recall Contrast or Brightness depend on sub-menu
Start up key function
1 2 P Write Burn-in flag to EEPROM (Enter Burn-in)
1 2 P Force into Burn-in mode, when power on no signal
1 2 P Clear Burn-in flag (Exit Burn-in mode)
1 2 P All mode recall function
Maintain key function by the Burn-in flag.
When Burn-in on: Enable the maintain key function
When Burn-in off: Disable the maintain key function
Maintain key function
1 2 P Enter Factory mode
OSD operation
1. Contrast: Adjust the ratio of luminance.
2. Brightness: Adjust the ratio of black level.
3. H.Size: Increase or decrease horizontal size of picture.
4. H.Position: Move the picture toward right or lift sides.
5. V.Size: Increase or decrease vertical size of picture.
6. V.Position: Move the picture toward top or bottom.
7. Pincushion: Cause right and lift sides become barrel or pin.
8. Pin Balance: Cause right and lift sides become balance curve.
9. Trapezoid: Adjust ratio between the horizontal size at top and the horizontal size
at bottom of picture.
10. Parallel: Cause the picture become parallel.
11. Moire: Adjust picture moire.
4.FRONT PANEL FUNCTION CONTROL DESCRIPTION
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OFF MODE IN 5 SEC.
CHECK
SIGNAL CABLE
MAIN MENU 2
1. iViewMeter: Show information of the input H/V frequency.
2. ViewMatch Color: Selectable color temperature include 9300K, 6500K and USER
3. Language: Provide OSD menu 5 languages for user to select.
4. Memory Recall: Reset picture’s parameters to the preset values.
DIAGNOSTIC MESSAGE:
When power is turned on a moment, but no signal input then show:
A. Signal Cable disconnection in any
condition.
B. PIN 5. In D-SUB is as Low / High
detection.
Display time : 5 seconds.
If monitor is on "power saving"mode, it will show:
A. Display time : 5 seconds.
B. Off mode in 5 sec. Display
massage
C. When entering power-saving, press
any key will re-display these
messages. Display time : 15 sec
If Horizontal, Vertical frequency are over range, it will show:
A. Display time : 5 seconds.
B. When entering power-saving, press
any key will re-display this
message. Display time : 15 sec.
H . V FREQUENCY
OVER RANGE
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