ViewSonic ViewPanel VP181 User manual

Service Manual
Viewsonic VP181
Model No. VLCDS21535-1
18” Color TFT LCD Display
ev. 1 — February 2000
ViewSonic® 381 Brea Canyon Road, Walnut, California 91789 USA - [phone]

Copyright
Copyright
©
1998
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
Description Of Changes
2/17/00 __| Initial Issue
ene
SOs
ii
VP181
Service
Manual

TABLE OF CONTENTS
WARNINGS
&
SAFETY
PRECAUPIONG
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iii
VP181
Service
Manual

/\, WARNING
This
service
information
is
designed
for
experienced
repair
technicians
only
and
is
not
designed
for use by the general public.
It
does
not
contain
warnings
or
cautions
to
advise
non-technical
individuals
of
potential
dangers
in
attempting
to
service
a
product.
:
Products
powered
by
electricity
should
be
serviced
or
repaired
only
by
experienced
professional
technicians.
Any
attempt
to
service
or
repair
the
product
or
products
dealt
within
this
service
information
by
anyone else could result in serious injury or death.
ViewSonic
Corporation
<4
{
Confidential
-
Do
Not
Copy
|

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 deflection circuits.
These voltages are exposed in such areas as the
associated flyback and yoke circuits.
3 FIRE & SHOCK HAZARD
3-1 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
munt
be
reinstalled
per
original
design.
Soldering must be inspected for possible cold solder
joints,
frayed
leads,
damaged
insulation,
solder
splashes
or
sharp
solder
points.
Be
certain
to
remove
all foreign material.
3-2
LEAKAGE CURRENT COLD CHECK
Unplug
the
AC
cord
and
connect
a
jumper
between
the
two
prongs
on
the
plug.
4-2 Turn the CRT display power switch “on”.
4-3 Measure the resistance value with an ohmmeter
between
the
jumpered
AC
piug
and
each
exposed
metailic 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 megohm minimum.
4
4-1
5 LEAKAGE CURRENT HOT CHECK
5-1
Plug
the
AC
cord
directly
into
the
AC
outlet.
Do
not
use
an
isolation
transformer
during
this
check.
5-2
Connect
a
1500
ohm,
10
watt
resistor,
paralleled
by
a
0.15uF
capacitor
between
each
exposed
metallic
part
and
a
good
earth
ground(as
shown
in
Fig.1).
5-3
Use
an
AC
voltmeter
with
1000
ohm/volt
or
more
Sensitivity
and
measure
the
AC
voltage
across
the
combination
1500
ohm
resistor
and
0.15uF
capacitor.
5-4
Move
the
resistor
connection
to
each
exposed
metallic
Part
and
measure
the
voltage.
Pe
5-5
Reverse
the
polarity
of
the
AC
plug
in
the
AC
outlet
and
repeat
the
above
measurement.
5-6
Voltage
measured
must
not
exceed
7.5
volt
RMS,
from
any
exposed
metallic
part
to
ground
A
leakage
current
tester
may
be
used
in
the
above
hot
check,
in
which
case
any
current
measured
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.
ViewSonic Corporation
SAFETY PRECAUTIONS
ne
Note:
High
voltage
is
present
when
this
CRT
display
is
operating.
Always
discharge
the
anode
of
the
picture
tube
to
the
display
chassis
to
prevent
shock
hazard.
AC VOLTMETER
15002, 10W
Fig. 1
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-
recommended
level.
Note:
It
is
important
to
use
an
accurate
periodically
calibrated
high
voltage
meter.
7-2
If
high
voltage
cannot
be
set
to
24kV,
immediate
service
is
required
to
prevent
the
possibiity
of
premature
component
failure.
7-3
To
prevent
X-Radiation
possibility
it
is
essentialio
use
the
specified
picture
tube.
IMPORTANT SAFETY NOTICE
There
are
special
components
used
in
this
CRT
displays
which
are
important
for
safety.
Thes:
parts
are
identified
by
the
international
symbd
‘\
on
the
schematic
diagram
and
on
th:
replacement
parts
list.
It
is
essential
that
thes:
critical
parts
should
be
replaced
with
manufacture’s
specified
parts
to
prevent
X
RADIATION,
shock,
fire,
or.other
hazards.
Dr
not
modify
the
original
design
or
this
will
voit
the
original
parts
and
labor
guarantee.
xa. SS
| Confidential - Do Not Copy |

Section
1
-
Engineering
Specifications
1. Scope
The
following
specifications
are
applicable
to
model
VP181,
18
inch
color
LCD monitor.
359.0 mm X 287.2 mm (typical)
Pixel
Pitch
0.281
mm
X
0.281
mm
Resolution 1024 x 768 dot (XGA)
Brightness 200 cd / m? (min.)
Contrast Ratio 200:1(min.)
Color 16,777,216
Viewing Angle Up 60° Down 60°(min.)
Left 60° Right 60°(min.)
CR>10:1
No
Analog 0.7 Vp-p / 750 Positive Polarity
Separate sync. TTL level
Composite sync
Digital
©
TMDS
(Panel
Link).
Video:
NTSC,
PAL,SECAM
30
kHz
to
95
kHz
(automatically)
Vertical
50
Hz
to
75
Hz
(automatically)
Non-interlaced
Max Pixel Rated 210Mhz
Horizontal 1280 dots
Vertical 1024 lines
Horizontal 359.0 mm (typical)
Vertical 287.2 mm (typical)
(Active
display
area
is
dependent
upon
signal
timings)
AC
adapter
input
AC90V-264V
50/60
Hz
DC
input
DC
12V
70W
On
mode
including
USB
less
than
12W
Suspend,
Standby
mode
less
than
8W
Off
mode(
1
input
signal
)
Current
Rating
{AC
input
1.0A
@AC
100-240V
fecemeree
lee
input
5A
@DC
12.0V
445
(W)
x
459
(H)
x
243
(D)
mm
Gross
514
(W)
x
616
(H)
x
315
(D)
mm
Depth(head
only)
100.5mm
ViewSonic
Corporation
3
VP181
CONFIDENTIAL
-
DO
NOT
COPY

Operating Temperature 0 to 40°C
Operating Humidity 8 to 80%
Storage Temperature -20 to 60°C(max. temp at 29%RH)
Storage Humidity 5 to 85%
AC cord with Power Supply 1
USB Upstream Cable base -> host PC
Analog VGA cable 1.8m
3.5mm Stereo Mini to 3.5mm
Stereo Mini PC Cable
3.5mm Stereo Mini to Dual RCA
Cable
RCA to RCA composite Video
Cable
Viewsonic CDRom
Environmental
Conditions
Accessories
,ISO , CE, DOC-
EPA,
NOM,
TUVIGS,
TUV/ERGO,
MPRII,
TCO99,
E2000
NEMKO,DEMKO,
SEMKO,FIMKO,Estonia,
Lithuania,
PCT,
SASO,
S.
Africa,
VCCI,
BCIQ,
CCIB,
S-Mark,
C-Tick,
User Control by On Screen Display( base only )
VESA DDC1/2B compatible ( head DDC2B only)
Cabinet Material - GE GP7351 Color code Y0487
7
ViewS
onic
Corporation
4
VP181
CONFIDENTIAL —- DO NOT COPY

3. Electrical Characteristics
Power Supply
3.1.1 AC Input (AC Adapter)
Input Voltage
Frequency
Power Consumption:
65W (typ)
less than 8W
Current Rating
3.1.2 DC Input
Input Voltage
Current Rating
3.2 LCD
LCD
Effective display size
Pixel number
Color filter arrangement
Display method
Drive method
Dot pitch
Pixel pitch
Dot number
Backlight
Brightness
Contrast ratio
Display color
Minimum viewing angle
Response time
3.3 Interface Signals
AC90-264V
47 1 63Hz
on mode
power save mode
1.0A @ AC100-240V
DC 12 V
5.0A
In-Plane
Switch
Active
matrix
(TFT)
359.0
(H)
x
287.2
(V)
mm
(typ)
18.1”
/
46
cm
diagonal
1280
x
1024
pixels
R.G.B.
vertical
stripe
TFT,
normally
black
In-Plane
Switch
Active
matrix
(TFT)
0.092
(H)
x
0.281
(V)
mm
0.281
(H)
x
0.281
(V)
mm
1280
x
1024
x
3
dots
Edge-lighting
type
with
6
CCFTs
(Cold
Cathode
Fluorescent
Tube)
200
ed
/
m2
(min:
center
/
all
white)
200:1
(min)
16,777,216
Up
60°
/
down
60°
/
right
60°
/
left
60°
(Contrast
ratio>10
at
Ta=25°C,
77°F)
25
msec
(Typical)
3.3.1 | RGB Video Signals
3.3.1.1 Separate Sync . Signals
Analog
R,G,B
0
-0.7
Vp-p
Signal Level 75 +5%
Sync Level TTL level
Sync
Polarity
independent
3.3.1.2
|
Sync
On
green(serrated
XGA
only),
Composite
Sync
3.3.2 | Composite Video Signals
3.3.2.1 Video type
NTSC, PAL,SECAM
ViewSonic Corporation
5
VP
181
CONFIDENTIAL — DO NOT COPY

3.3.3 Audio Signals
3.3.3.1 Audio Input Ports
2channels x 2
3.3.3.2 Speakers
2W(max.) x 2
3.3.4 — Input Signal Connectors
3.3.4.1 RGB Video Input : 15 pin mini D-sub
PortA
pC GROUND
| 6 TC GROUNDT
| 8
| Lo
GROUND
GROUND
H.SYNC
V.SYNC
Port B
Separate Sync
[/
5
___|_______GROUND_————
J
[6
|
_____
GROUND
[__7___[-____GRoUND
[8
[_______
GROUND
J
[9
[No
connection
J
-
40
[_____
GROUND.
[SYNC
[____VSYNC
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6
VP181
CONFIDENTIAL
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sO OOOO:
rw OOOOOs
sbOOO0O0On
3.3.4.2
|
Composite
Video
Connector
RCA
jack
x
1,
S-video
x
1
(Not
individually
selectable)
3.3.4.3.
Audio
Connector
3.5mm
Stereo
jack
x
2,
3.5mm
Microphone
Passthrough
jack
x
2
3.3.5
Signal
Timing
3.3.5.1
Timing
Mode
10
Timing
Mode
Memory,
circular
use
when
new
mode
detected
3.3.5.2 | Timing mode Change
maximum
time
for
mode
Change
10
sec.
3.3.5.3. Signal Timing Table
The
factory
test
input
video
signal
is
defined
as
the
following
table:
SYN
POL.
r
SYN| SYNC
MOD
[i][s1489s05KHe
|
7o0st
He
|
+
[=
|
640xa00(7)|
___TBMVEA
[MOD
aI]
31.46920.5KHe
|
S.84a7He|-
|__|
B40XABO(ED)
__MODIai|
34.97
s08KH
|
68.67a15he[
=
|
|
6a0Xa80(65)
|
—_
MAC
MOD
[al]
37.66
205KHe
["72etstsHe|-
|
=
|
_6a0xa80cra)
/_MOD
ISI]
375
e08KHiz
|
76a
eRe
[|
(|
__
6AOXAB0(75)
MOD
BO0XB00(72)
CE
MAC
MOD
[13]
48.363
+0.5KHz
|
60.0215Hz
[=
|=
|
1024X768(60)
MOD
[ra]
68.476
20
5KH2
|
70.021.5He
[=
[=|
TO24R768(70)|
—
VESA
STANDARD
|_MOD
[re
601025
20.5KHe
|
76.021.6Hz
[+
[+
|
TO2aX768(78)|
VEGA
STANDARD
MOD
[6]
54348
20.5KHe
|"
600621.5H2
|
+
[+
|
THS2XB6A(60)|
—
VESA
STANDARD
MOD
TIT]
65.851
.5KHe
[70.01
et.SHz
|
+
[+
|
TiS2XB64(70)|
—
VESASTANOARD
MOD
[ra
67.5
s08KHz
[7603452
[+
|
+
|
TiS2k864(75)|
—
VESASTAN
MOD
[re]
60.0020.5kHe
|
600z4.5Hz
[+
[+
|
1280KG60(60)|
—
VESASTAR
VESASTAN
[MOD
ety
70.876
x0.5KHe
|
75.034
5H
VESASTAR
MOD
[22]
75.000
0.5KHz
|
60.0
+1.5Hz
VESA
STAN
MOD
Pa]
67.250
05KHe
|
6BOHi.5he
|
ViewSonic
Corporation
7
VP181
V.sync
Video
Mode
Frequency
Preset
No.
H.sync
Frequency
Description
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CONFIDENTIAL
—-
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