ViewSonic A90f+-1 VCDTS23307-2R User manual

Service Manual
ViewSonic A90f+-1
Model No. VCDTS23307-2R
19” Digital Controlled Color Monitor
(A90f+-1_SM_602-Rev. 1.0-October 2002)
ViewSonic381 Brea Canyon Road, Walnut, California 91789 USA - [phone]

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 10/9/02 Initial Release DCN-2658 K.Yang
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1b 11/05/02 Revise DCN-2658 C.Shen

TABLE OF CONTENTS
1. Precautions and notices ......................................................1
2. Specification.......................................................................3
3. Control Location and Functions ........................................5
4. Disassembly instructions ...................................................9
5. General Connections & applications ...............................11
6. Electronic Circuit Description .........................................13
7. Adjustment ......................................................................19
8. Troubleshooting Flow Chart.............................................28
9. Recommended Spare Parts List........................................35
12. PCB Layout.....................................................................54
13.Schematic Diagram.........................................................57
14.Exploded Diagram.......................................................... 64
11.Block Diagram................................................................53
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10. Electrical Parts List.........................................................37

1. Precautions and Notices
1.1 SAFETY PRECAUTIONS
1) Observe all cautions and safety related notes located inside the display cabinet and on the display
chassis.
2)Operation of this display outside the cabinet or with the cover removed, may involves a shock harzard
from the display power supplies. Work on the display should not be attempted by anyone who is not
thoroughly familiar with precautions necessary when working on high voltage equipement.
3)Do not install, remove or handle the picture tube in any manner unless shatter-proof goggles are worn.
People not so equiped should be kept away while handling picture tube. Keep picture tube away from
body while handling.
1.2 Observe all cautionary and safety related notes located on the chassis, cabinet and display tube.
1.3 Operation of the monitor with the back cover removed presents a potential shock hazard. Only
personnel familiar with the precautions necessary for safe working on high voltage equipment should
attempt to carry out servicing.
1.4 Always wear shatter proof goggles when removing, installing or generally handing the picture tube.
People not so equipped should be kept at a safe distance when any such handing is being undertaken.
Do not handle the picture tube by the neck of deflection coil. Do not carry the picture tube resting against
the body.
1.5 The picture tube is designed and constructed to limit X-Radiation to a safe level during normal operation.
To maintain the required level of protection and safe operation, replacement tubes must be correctly
adjusted and any protective circuits must not defeated.
1.6 IMPORTANT-Safety Tests
After servicing, and before returning the monitor to the user, a thorough safety test must be carried out
to ensure there is no potential shock hazard to any operator(s) using the monitor.
All the following test must be performed. A monitor failing any of these tests should be rejected and have
the problem rectified.
1.7 A.C. Leakage Test
Remove the power sourse. Connent the monitor to the circuit as in figure 1 below. Switch the monitor
on/off switch to on. A reading of less than 3.5mA should obtained (ref. EN60950).
Equipment safety
Earth terminal
Equipment
Under test
Measuring instrument
Isolating
transformer
L
N
Fig. 1 Measurement of AC Leakage Current
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1.8 Voltage Breakdown Test
Connent the live pin and neutral pin together. Switch the monitor on/off switch to on. Apply 1500VAC
RMS or 2250VDC, 50Hz for one minute between this connection point(live and neutral pin short) and
earth. Ensure no voltage breakdown occurs.
1.9 Earth Resistance/Continuity Test
Measure the resistance between the signal cable metal shell and the earth pin in the A.C. socket. At a
current of 25 amperes, the resistance should be less than 500mohm.
NOTE: A portable appliance tester (PAT) is a suitable instrument to use for the above safety tests.
1.10 H.V. Over Voltage Protection (Required for X-Radiation Safety)
Adjust R176 slowly anti-clockwise until the over voltage protection circuit is activated, and the high
voltage must be less than 33KV just before the activation. After test, R176 should be adjusted back to
normal(=25.9KV)
CAPACITOR:
C850 400V 4700PFM CAPACITOR.CERAMIC 5230105501
C851 400V 4700PFM CAPACITOR.CERAMIC 5230105501
C135 250V 33UFM CAPACITOR.ELECTROLYTIC 5214433012
C139 100V 330UFM CAPACITOR.ELECTROLYTIC 5214019612
RESISTOR
R827 1/4w 2K ohm RESISTOR.VR 5162161220
SEMICONDUCTORS
I803 UC3842N IC LINEAR 6644063111
I301 TDA9116 SDTP-32 IC.LINEAR A.S.D.C. 6644076308
I310 TDA8172 7P IC.LINEAR 6644076000
I101 UC3842N IC.LINEAR 6644063111
IA01 NT68F62U SDIP-42 IC.LSI MCU 6647008204
Q121 2SK2843 TR FET MOS 6626003202
Q433 BU4525AX TR NPN 6621002801
Q801 2SK2648 TR FET MOS. 6626003208
D827 HZ5C1 DIODE ZENER 6615007834
OTHERS
SR801 CSA-SS-212DM5 RELAY 5054613402
F801 250V/3.15A FUSE 5054431539
T801 TPW-697 POWER TRANSFORMER 5061369700
T101 (RA) TFB-280T TRAQNS.FLYBACK COLOR 5062628031
T101 (RB) TFB-280L TRAQNS.FLYBACK COLOR 5062628032
V901 (RA) M46QCK761X123 (TCO
MDT)
CCRT/DY 5051286346
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2. Specifications
Size and deflection angle 19 inch 90 degree
Screen type Pure, Flat, High Brightness
Horizontal pitch / Dot pitch 0.22mm / 0.25mm
Surface treatment Anti-static AR coating
CDT
Transmission rate 52.6%
Horizontal Frequency 30kHz to 86kHz
Scanning
Freq. Vertical Frequency 50Hz to 150Hz
Video amplifier Applicable pixel rate 175MHz
Resolution Maximum 1600 x 1200
Modes Factory preset/User modes 13 / 10
AC input range 100 to 240 Vac
Max. power consumption 110W
Normal <110 W
Power
Power Management Off <3 W
Power Switch On/off with Led indicator
Up/Down adjustment Key
2 key pads for adjust
Up / down keys are direct access for Contrast
And Brightness adjustment
“1” “ 2” Key As a select key/ go to next sub menu
User controls
“UltraBrite Mode “Key As a select key/ go to High Bright Display mode
Signal
connections
Standard Model 1.8 m signal cable with 15Pin D shell miniature
male connector.
Rear
connection
Power input AC socket with 1.8 meter cable
Safety CB,
Emissions EN50081-1
Immunity EN50082-1
ISO9241Paart3 &ISO9241Part8
Ergonomic
VLMF MPRII
European
EPA Energy Star
Safety UL1950, Cul950 or CSA 22.2
Emissions FCC class B
USA
X-ray DHHS
Regulatory Filing VCDTS23307-XYZ
Agency
Approvals
Plug and Play DDC 1/2 B Version 2
Operating Temperature
Storage Temperature
0qC to 40qC
–40qC to +60qC
Operating Humidity 10% to 90%
Environmental
Conditions
Storage Humidity 10% to 95 %
Dimensions W x H x D 575 mm x 600mm x 630mm
Weight Kg 25.5Kg (Gross)
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Noted that A90f + belong to MPR II models.
Alignment default conditions:
3.1 Room luminance: 225 LUX.
3.2 Warm up: Mis-convergence: 30 minutes (Full white display).
Other spec.: 20 minutes.
Display usable: 15 sec.
3.3 CDT direction : East
3.4 Pattern generator : CHROMA 2250 or equivalent.; (Video O/P: 0.7 Vpp).
3.5 Earth Magnetic field:
Northern Hemisphere: Bh : 0.25 +/- 0.01 GAUSS ; Bv : 0.45+/- 0.01 GAUSS –U03 model.
Southern Hemisphere: Bh : 0 +/- 0.01 GAUSS , Bv : -0.52 +/-0.01 GAUSS.
3.6 AC Power input: 110V AC, 50/60 Hz ;230V AC ,50 /60Hz.
3.7 Ambient temperature: 20 ²5 ʑ.
3.8. Preset Mode Timing: Total 13 Pre-set Modes + 1 mode (mode 5 for self test setup)
MODE RESOLUTIO
N
H X V
NO.
H.FREQ
(kHz)
V.FREQ(
Hz)
H.
POLART
Y
V.
HORIZ.
TOTAL
USEC
H.
DISPLAY
USEC
H.BACK
PORCH
USEC
H.SYNC
WIDTH
USEC
VERT.
TOTAL:
MSEC
V.DIS-
-PLAY
MSEC
V.BACK
PORCH
MSEC
V.SYNC
WIDTH
MSEC
VIDEO
RATE
MHz
VGA 640 X 480
1
31.469
59.94


31.778 25.422 1.907 3.813 16.683 15.253 1.049 0.064 25.175
VGA 640 X 400
2
31.469
70.078
-
+
31.779 25.422 1.907 3.813 14.269 12.712 1.112 0.064 25.175
MAC 640X480
3
35.0
66.667
Composit
e
Negative
28.571 21.164 3.175 2.116 15 13.714 1.114 0.086 30.24
640X480
4
37.5
75


26.667 20.317 3.81 2.032 13.333 12.8 0.427 0.080 31.5
VESA
85Hz
640 X 480
5 (for
auto-size
reference)
43.269
85.008


23.111 17.778 2.222 1.556 11.764 11.093 0.578 0.069 36
VESA
75Hz
800 X 600
6
46.875
75
+
+
21.333 16.162 3.232 1.616 13.333 12.8 0.448 0.064 49.5
MAC 832X 624
7
49.725
74.5


20.111 14.524 3.910 1.117 13.414 12.549 0.784 0.06 57.28
800 X 600
8
53.674
85.061
+
+
18.631 14.222 2.702 1.138 11.756 11.179 0.503 0.056 56.25
VESA
75Hz
1024 X 768
9
60.023
75.029


16.660 13.003 2.235 1.219 13.328 12.795 0.466 0.050 78.75
1024 X 768
10
60.241
74.927

16.6
12.8 2.2 1.2 13.346 12.749 0.498 0.05 80
VESA
85Hz
1024 X 768
11
68.677
84.997


14.561 10.836 2.201 1.016 11.765 11.183 0.524 0.044 94.5
1600 X 1200
12
75.0
60


13.333 9.877 1.877 1.185 16.667 16 0.613 0.04 162
VESA
75Hz
1280 X 1024
13
79.976
75.025


12.504 9.481 1.837 1.067 13.329 12.804 0.475 0.038 135
VESA 1024 X 768
14
48.363
60.004


20.677 15.754 2.462 2.092 16.666 15.880 0.600 0.124 65
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3. Control Location and Functions
Power switc
Led indicator
U
p
“2” key
Down
“1” ke
y
Power switch
Auto Sizing
Front view
Rear view
UltraBrite
Mode
UltraBrite Mode
15 pin D Sub
AC input
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4.1. Function Key adjustment Description:
(a). Power switch: This is a “software “Key, Turns the display on and off. The power indicator will
light “Green”, when the display is on.
“1” key: Turn (on /off) OSD menu.
Key: Down side to select item / decrease value
Key: Up side to select item / increase value
: Keys can directly access Contrast / Brightness adjustment
(b). “2“key: a select key or go to next sub menu.
(c). Pressing “2 & power” key at same time to switch monitor on and then pressing “1” Key will
enter factory optimized OSD Menu (see Fig. 0)
(d). Selected icon and then pressing “2” key will demagnetize CDT.
(e). High Brightness Key ( UltraBrite Mode ): this key will be effective only after switching on
monitor
(not in preset state), Pressing this key will switch normal brightness to high brightness.
The next pressing will return to normal brightness.
In preset menu, Sup93 / Sup65 / Sup50 represent the high brightness of 9300K / 6500K /
5000K.
(f). Autosizing Key: pressing this key will automatically adjust the display to a proper setting.
Note this function only work precisely after all preset modes being set up.
For Autosizing reference, all maually set up preset modes must be saved by pressing “head
“ Icon.
Fig. 0 Factory OSD Menu
4.2 User OSD menu descriptions
Press “1” key to display a basic main menu (1) shown as below.
FIGURE 1( USER MODE OSD MENU 1)
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Using and keys to move a cyan window bar to get your desired items. If it is selected,
Then pressing “2” key to display
Sub menu as below to start adjustment.
Using and to decrease / increase value on selected item. Noted that the menu can do two
items adjust
by pressing “2” key, it will change to another one in toggle.
In main menu (1), move the cyan window bar up to the first item or down to the last item, then the
next bar moving will enter main menu (2) as below for other adjustment.
FIGURE 2 ( USER MODE OSD MENU 2)
In main menu 2, if “ VIEWMATCH COLOR” is selected, then pressing “2” key will display
color sub menu as the following
The three default color modes (9300k, 6500k, 5000k) are factory preset, User can select these
default colors but can’t adjust and save.
If “USER COLOR” is selected, then pressing “2” key will display next sub menu as below to start
color adjustment.
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