ViewSonic ViewPanel VGI50 User manual

Service
Manual
ViewSonic
VGI50
ViewPanel
—
Model
No.
VLCDS21457-1
15”
Active
Matrix
LCD
Color
Monitor
(Rev. 1 — April 1999)
ViewSonic®
381
Brea
Canyon
Road,
Walnut,
California
91789
USA
-
(800)
888-8583.

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 Approval
~ 4/29/99 Initial Issue
ii
VG150
Service
Manual

TABLE OF CONTENTS
PRECAUTIONS
AND
SAFETY
WARNINGS
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7
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iii
VG150
Service
Manual

ViewSonic
Service
Manual
April
1999
-
Version
1.0
VG150
ene
A
FCC INFORMATION
This
equipment
has
been
tested
and
found
to
comply
with
the
limits
of
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
if
not
installed
and
used
in
accordance
with
the
instructions,
may
cause
harmful
interference
to
radio
communications.
However,
there
is
no
guarantee
that
the
interference
will
not
occur
in
a
particular
installation.
If
this
equipment
does
cause
unacceptable
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
--
reorient
or
relocate
the
receiving
antenna;
increase
the
separation
between
equipment
and
receiver;
or
connect
the
into
an
outlet
on
a
circuit
different
from
that
to
which
the
receiver
is
connected.
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.
Also,
any
unauthorized
changes
or
modifications
to
Amtrak
products
will
void
the
user’s
authority
to
operate
this
device.
Thus
AmTRAN
will
not
be
held
responsible
for
the
product
and
its
Safety.
:
CE CERTIFICATION
This
device
complies
with
the
requirements
of
the
EEC
directive
89/336/EEC
with
regard
to
“Electromagnetic
compatibility.”
SAFETY CAUTION
Use
a
power
cable
that
is
properly
grounded.
Always
use
the
AC
cords
as
follows
—
USA
(UL);
Canada
(CSA);
Germany
(VDE);
Switzerland
(SEV);
Britain
(BASEC/BS);
Japan
(Electric
Appliance
Control
Act);
or
an
AC
cord
that
meets
the
local
safety
standards.
Page 1
iContidential Do Not Copy,
me eerial 0 Not Copy,

Service
Manual
ViewSonic
VG150
April
1999
-
Version
1.0
Features
The
VG150
are
world
class
TFT
LCD
analog
display
monitors
that
include
the
following
features.
1. Digital On Screen Display Controls
User
friendly
buttons
(Power,
Function,
Select
(+
/-),
Auto)
allowing
for
picture
perfect
quality.
User
can
define
display
mode
or
reset
to
default
settings.
Help
menu
contains:
Auto-Sync;
Contrast;
Brightness;
OSD
H-Pos;
OSD
V-Pos;
Color; LCD Adjust; MISC and Exit.
2. Power Supply Support
Ability
to
accept
voltages
from
100~240
Vac
(Universal),
thus
allowing
a
full
range of input AC power supply.
3. Power Saving System
This
environmental
friendly
product
is
able
to
reduce
power
consumption
by
75%
in
Suspend
Mode
and
by
more
than
95%
in
Off
Mode.
4. Frequency Range
Monitor
can
support
video
standards
from
VGA
to
XGA,
where
Horizontal
frequency
ranges
from
30~62kHz
and
Vertical
frequency
ranges
from
50~75 Hz.
Page 2
Confidential Do Not Copy

ViewSonic
April 1999 - Version 1.0
SPECIFICATIONS
Service Manual
VG150
Characteristic
LCD Panel
Maximum Viewing
Angles
Signal Input
Connector
Maximum Resolution
Video Bandwidth
Display Area
Power Voltage
Power Consumption
Operating Conditions
Storage Conditions
Dimensions
Weight
ADI, 15.0 inch diagonal viewable screen, Anti-glare TFT
Active Matrix Panel, 0.297 mm pixel pitch, TDK Inverter
Left : 60°
Right : 60°
Up : 45°
Down : 55°
Video : RGB analog, 0.7 Vp-p, 75 ohms
Sync : H/V separate or composite sync, TTL
Horizontal : 30~62 kHz
Vertical : 50~75 Hz
15 Pin Mini D-Sub
1024x768
100 MHz nominal
304.4mm (H) x 228.1mm (V)
100~240Vac @ 50 ~ 60 Hz (auto switch), 12Vdc 3A
38 W max.
Temperature : 325 to 1047 (07 to 407)
Humidity : 10% to 90% (no condensation)
Altitude : To 10,000 feet
Temperature : -4& to +1402 (-202 to +607)
Humidity : 10% to 90% (no condensation)
Altitude : To 10,000 feet
Physical : 390mm (W) x 372mm (H) x 138mm (D)
5.0 kg
Page 3
(Confidential Do Not Copy:

Service Manual
VG150
ON SCREEN DISPLAY
ViewSonic
April 1999 - Version 1.0
OSD (On Screen Display) function is supported on each the TFT LCD analog
display monitors and is controlled by four easy to use buttons — Power, Function,
Select (+), Select (-), Auto.
Sub-Funetion
Auto Sync
Contrast
Brightness
OSD H-POS
OSD V-POS
Color
LCD Adjust
Preset 1
Preset 2
Red
Green
Blue
H Size
H Position
V Position
Fine Tune
Auto sync
Invisible
Smoothing
Information
Language
Recall
Main menu
Page 4
(Contidential Do Not Copy,
0 ~ 100
0 ~ 100
0 ~ 100
0 ~ 100
0 ~ 100
0~ 100
0 ~ 100
ON/OFF
ON/OFF

ViewSonic Service Manual
April 1999 - Version 1.0 , VG150
FACTORY PRESET TIMINGS
This timing chart is already preset for the TFT LCD analog display monitors.
Timing Horizontal | Horizontal | Vertical Vertical
Polarity |Frequency| Polarity | Frequency
VGA 640x350 31.47 kHz 70.08 Hz
VGA 720x400 31.46 70.08
VGA 640x400 31.46 70.08
VGA 640x480 31.47 60.05
VESA 640x480 37.86 72.81
VESA 640x480 37.50 75.00
MAC 640x480 35.00 66.66
VESA 800x600 35.15 56.25
VESA 800x600 37.87 60.31
VESA 800x600 48.07 72.18
VESA 800x600 46.87 75.00
VESA 1024x768 48.36 60.00
VESA 1024x768 56.47 70.06
SVGA 1024x768 58.03 71.94
VESA 1024x768 60.02 75.02
MAC 1024x768 60.24 74.92
Page 5
{Confidential Do Not Copy,

Service Manual
VG150
PIN ASSIGNMENT
ViewSonic
April 1999 - Version 1.0
The TFT LCD analog display monitors use a 15 Pin Mini D-Sub connector as video
Pin | Description _|
input source.
oO On OO fF WN =
ek ako ke ae ee a B&B WwW HO = O
Red
Green
Blue
Ground
Ground
R-Ground
G-Ground
B-Ground
No Connection
Ground
No Connection
(SDA)
H-Sync (Composite Sync)
V-Sync
(SCL)
Page 6
{Confidential Do Not Copy,

ViewSonic Service Manual
April 1999.- Version 1.0 VG150
BLOCK DIAGRAM
COMPLETE TFT LCD DISPLAY UNIT
AC Outlet Adaptor
| |
fe see nee ;
12V | favarar 700Vac
|
}
|
ae
Main Board | Digital! ter |
t
, Signal’ | LCD
Panel
{
H
i
|
| |
MAIN BoaRD (TFT LCD DisPLay ANALOG INTERFACE CONTROL BOARD)
G-anolog
B-anolog
Digital Rout
Control Data G out
registers processor Bout
Control
Unit i
| Dot CLK
H-Sync-in
V-Sync-in
a P —
CPU haan Clock generator Soilless
ry
cog
==
i
H-Sync-out
|_vesyne _| eee eee vee
icp | 2 | a pos Data Enabie
Page 7
‘Confidential Do Not Copy,

Service Manual
VG150
MAIN
BOARD
I/O
CONNECTIONS
W04
CONNECTION
(LEFTORIGHT)
"OSD
CONTROL"
we Kobe
" Function " Key
mg Key
Recall
LED 1
LED 2
Ground
Power 1
oon oa hr WwW DN
Power 2
W05
CONNECTION
(TOPDOBOTTOM)
"INVERTER
CONTROL"
+42V
Ground
V Enable
CON
No Connection
Page 8
‘Contidentia fot Copy,
ViewSonic
April 1999 - Version 1.0

ViewSonic
April 1999 - Version 1.0
Service Manual
MAIN BOARD I/O CONNECTIONS
W07 CONNECTION "VIDEO SIGNAL OUT TO LCD PANEL"
VG150
Fin | __Deeeipon
N.C.
N.C.
N.C.
N.C.
N.C.
Red Odd Data Signal (LSB)
Ground
Red Odd Data Signal
Red Odd Data Signal
Red Odd Data Signal
Red Odd Data Signal
oO Oo nN OAH kh WN A
—
oO
—_ —_
— NO
13 | Red Odd Data Signal
14 | Red Odd Data Signal
15 | Ground
=
o
Red Odd Data Signal (MSB)
Green Odd Data Signal
_ “I
48 | Green Odd Data Signal (LSB)
19 | Green Odd Data Signal
20 | Green Odd Data Signal
21 | Green Odd Data Signal
22 | Green Odd Data Signal
23 | Green Odd Data Signal (MSB)
24 | Green Odd Data Signal
25 =} Blue Odd Data Signal (LSB)
26 | Ground
27 | Blue Odd Data Signal
28 | Blue Odd Data Signal
29 | Blue Odd Data Signal
w Oo
Blue Odd Data Signal
Pin} __Deseipton__
Blue Odd Data Signal
Blue Odd Data Signal
Ground
Biue Odd Data Signal (MSB)
Red Even Data Signal
Red Even Data Signal (LSB) .
Red Even Data Signal
Red Even Data Signal
Red Even Data Signal
Red Even Data Signal
Red Even Data Signal (MSB)
Red Even Data Signal
Green Even Data Signal (LSB)
Ground
Green Even Data Signal
Green Even Data Signal
Green Even Data Signal
Green Even Data Signal
Green Even Data Signal
Green Even Data Signal
Ground
Green Even Data Signal (MSB)
Blue Even Data Signal
Blue Even Data Signal (LSB)
Blue Even Data Signal
Biue Even Data Signal
Biue Even Data Signal
Blue Even Data Signal
Blue Even Data Signal (MSB)
Blue Even Data Signal
Page 9
(Confidential Do Not Copy

Service Manual
VG150
MAIN BOARD I/O CONNECTIONS
ViewSonic
April 1999 - Version 1.0
W07 CONNECTION "VIDEO SIGNAL OUT TO LCD PANEL"
fin | __Besotton
Ground
Ground
V Sync Signal
Ground
Data Enable Signal
H Sync Signal
Ground
Ground
Dot Clock
Dot Clock
Page 10
Ein | __Desetpten
Ground
Ground
Power of LCD
Power of LCD
Power of LCD
Power of LCD
N.C.
N.C.
N.C.
N.C.
(Contidential Do Not Copy

ViewSonic
Service
Manual
April
1999
-
Version
1.0
VG150
INVERTER
BOARD
I/O
CONNECTIONS
V-out
V-out
GND
GND
V-control
ON/OFF
GND
12V
NOTE:
MANUFACTURER’S
NAME MUST
BE
ON
THE
PRINTED
SIDE
FOR
THE
INVERTER
BOARD
TO
BE
FACING
UP.
Page 11
(Confidential Do Not Copy,

Service
Manual
ViewSonic
VG150
April
1999
-
Version
1.0
THEORY OF CIRCUIT OPERATION
The
VG150
are
multi-frequency
and
multi-mode
color
TFT
LCD
monitors.
It
supports
true
XGA
resolution
of
1024x768
including
SVGA,
VGA
and
other
various
high
resolution
modes
up
to
1024x768
for
IBM,
PC
compatibles,
Power
PC
and
Macintosh.
The
TFT
LCD
panel,
with
a
0.288
mm
pixel
pitch,
provides
sharp
flicker-free
images.
As
the
previous
block
diagram
illustrates,
the
VG150
uses
the
Analog
Interface
Controller
(IC20)
ASIC
for
mode
detection
and
resolution
amplifying
from
its
preset
values.
The
purpose
of
the
two
set
of
PLL
is
to
provide
the
clock
from
multiple
horizontal
synchronous
frequencies.
PLLO
provides
A/D
converter’s
sample
clock
with
the
1CS1523
(IC09)
while
PLL1
produces
the
LCD
panel’s
dot
clock
with
the
TLC2933
(IC03).
Furthermore,
each
TFT
LCD
monitor
uses
the
24LC21
(IC14)
chip
to
provide
DCC1™
and
DCC2B™
with
Plug&Play.
Also
included
in
each
monitor
is
a
mode
detection
feature
to
examine
the
H-Sync
frequency
input
level
to
decide
for
power
saving
mode.
Power
saving
will
shut
down
certain
components,
including
excess
electrical
power
to
reduce
power
consumption.
Upon
receiving
video
signal
input,
the
Analog
Interface
Controller
(Digital
Process
and
Control
System)
will
trigger
the
mode
detection
function
such
that
the
internal
controls
can
use
the
ROM'’s
preset
information
to
drive
the
Analog
Interface
Controller.
In
addition,
the
preset
values
can
determine
A/D
converter
clock:
LCD
dot
clock;
line
buffer
input/output
rate;
V-Sync
and
H-Sync
pulse
width;
back
porch
and
front
porch
to
provide
optimal
performance
for
the
TFT
LCD
monitors.
Digital
process
and
control
system
allows
users
to
control
OSD
menu
values
to
change
monitor
settings
that
includes
audio
volume,
contrast,
brightness,
color,
H/V
position,
and
H
size.
The
following
sections
are
a
breakdown
of
the
TFT
LCD
display
control
board’s
major
sections.
Page 12
(Confidential Do Not Copy.

ViewSonic
Service
Manual
April
1999
-
Version
1.0
VG150
THEORY
OF
CIRCUIT
OPERATION
2
+ 52.
2
we
7
Shed
=.
wT
earrorsy
cn
am
ed
cee:
yeas
et
eee
9
w
ine
nas
“ mec HEE ey we
*
aA dS |
ance on
ATT
rove = a *cv0
Perera we) venti rere
vo -
7 ot
re -
fae
vecmnnrn
cove
eves LD
ve
GrneiNe7.8
iin
| |
|
. A
fs]
Note:
For
a
more
legible
version
of
this
drawing,
:
refer
to
the
Schematic
on
page
59.
-
This
product
uses
74HC4053
as
a
signal
switch
in
order
to
support
Composite
SYNC
and
SYNC
on
Green
timings.
The
MPU(IC25)
in
this
product
provides
the
differentiation
function
to
the
Composite
SYNC,
so
the
SYNC
processor
circuit
is
simplified.
The
free
run
function
in
this
product
also
make
user
to
easily
know
the
input
signal
is
out
of
product
specification
or
interrupted.
When
separated
SYNC
is
detected
through
the
V-in
and
H-in,
MPU
will
set
both
the
H-select
and
V-select
to
low
level.
If
the
composite
SYNC
is
detected,
the
H-select
is
low
level
and
V-select
will
be
high
level.
If
the
SOG
is
detected,
both
H-select
and
V-select
are
in
high
level.
V-com
is
the
vertical
SYNC
separated
from
the
Composite
SYNC
through
MPU.
lf
the
input
signal
is
out
of
specification
or
interrupted,
the
free
run
mode
will
be
activated.
The
free
run
SYNC
comes
from
the
pin
39
and
40
of
IC02.
At
this
condition,
the
Hync-cut
is
low
level
and
the
pin
1
of
ICO6
is
always
high
level.
Above
condition
plus
the
condition
that
the
free
run
enable
is
also
in
high
level,
the
\V-free
and
H-free
will
activate
the
free
run
mode.
Page 13
Confidential Do Not Copy

Service
Manual
ViewSonic
VG150
April
1999
-
Version
1.0
THEORY OF CIRCUIT OPERATION
This
product
supports
timing
from
VGA
to
XGA,
so
the
pixel
rate
is
from
25
MHz
to
80
MHz.
In
order
to
make
the
phases
of
sampling
clock
and
video
to
be
closed
to
each
other
easily
and
precisely
when
user
uses
the
find
tune
function,
the
phase
delay
effect
in
the
high
pixel
rate
is
smaller
than
that
in
the
low
pixel
rate.
The
MPU
will
choose
the
proper
phase
adjustment
circuit
through
the
pin
4
of
IC25,
fine
tune
select.
The
fine
tune
control
is
a
PWM
signal.
When
I?C
changes
the
control
register
the
MPU
also
changes
the
fine
tune
control
duty
cycle.
The
changed
duty
cycle
will
become
DC
level
through
R89
and
C104.
When
detecting
pixel
rate
larger
than
50
MHz,
the
MPU
will
set
the
fine
tune
select
to
high
level.
If
the
pixel
rate
is
smaller
than
50
MHz,
the
fine
tune
select
will
set
to
low
level.
The
R52,
R59,
R80
and
C103
are
all
phase
adjustment
components.
This
product
supports
DDC
1/2B
by
using
24LC21.
The
24LC21
is
a
128x
8
bits
EEPROM.
This
chip
is
designed
to
use
in
applications
requiring
storage
and
serial
transmission
of
configuration
and
control
information.
Two modes
of
the
operation
have
been
implemented,
the
Transmit
Only
mode
and
Bi-Directional
mode.
Upon
power
up,
this
device
will
be
in
the
Transmit
Only
mode,
sending
a
serial
bit
stream
of
the
entire
memory
array
contents,
clocked
by
the
VCLK
pin.
A
valid
high
to
low
transition
on
the
SCL
pin
will
cause
the
devise
to
enter
the
Bi-Directional
mode
with
byte
selectable
read/write
capability
of
the
memory
array.
Page 14
(Confidential Do Not Copy,

ViewSonic
Service
Manual
April
1999
-
Version
1.0
VG150
THEORY
OF
CIRCUIT
OPERATION
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Note:
For
a
more
legible
version
of
this
drawin
;
yey.
Rae
——
refer to the Schematic on page 59.
AM30
is
a
triple
8-bits
A/D
converter
optimized
for
XGA
LCD
monitor
with
maximum
sample
rate
of
96
MSPS.
It
can
support
both
single-channel
and
dual-
channel
digital
outputs.
The
analog
input
range
of
AM30
is
(0.6V
~
2.6
V).
The
external
top
reference
voltage
(2.6V)
and
bottom
reference
voltage
(0.6V)
reference
voltage
is
required.
AM100
is
a
highly
integrated
analog
interface.
The
analog
input
R.G.B.
signals
are
first
sampled
by
six
channels
of
A/D
converter
(AM30,
choose
dual-channel
digital
output)
and
the
48-bits
R.G.B.
data
are
then
fed
into
Page 15
(Contidential Do Not Copy,

Service
Manual
ViewSonic
VG150
April
1999
-
Version
1.0
THEORY OF CIRCUIT OPERATION
AM100
The
AM100
is
capable
of
performing
automatic
detection
of
the
display
resolution
and
timing
of
the
input
signals
generated
from
various
graphic
cards.
The
AM100
then
automatically
scales
the
input
image
to
fill
the
full
screen
of
the
LCD
monitor.
The
AM100
can
interface
with
TFT
LCD
panels
from
various
manufacturers
by
generating
48-bits
R.G.B.
signal
to
the
LCD
panel
based
upon
the
timing
parameter
saved
in
the
EEPROM
(IC07).
The
AM100
has
the
following
major
functions;
1. Input mode detection.
2. Auto calibration.
3. Image scaling.
4. Image interpolation.and dithering.
5. OSD mixer.
The
following
sections
will
describe
the
functions.
Input Mode Detection
The
AM100
can
automatically
detect
the
mode
of
the
input
signal
without
any
user
adjustment
or
driver
running
on
the
PC
host
or
external
CPU.
It
automatically
detects
polarity
of
input
synchronization
and
the
sizes
of
back
porch,
valid
data
window
and
the
synchronization
pules
width
in
both
vertical
and
horizontal
directions.
The
size
information
is
then
used
not
only
to
decide
the
input
resolution,
to
generate
the
frequency
driver
for
the
input
PLL.
To
lock
with
HSYNC,
but
also
to
automatically
scale
the
image
to
full
screen,
and
to
synchronize
the
output
signal
with
the
input
signal.
The
detection
logic
is
always
active
to
automatically
detect
any
changes
to
the
input
mode.
Auto Calibration
The
AM100
can
automatically
calibrate
the
phase
of
the
sample
clock
in
order
to
preserve
the
bandwidth
of
input
signal
and
get
the
best
quality.
The
AM100
implements
a
proprietary
image
quality
function.
During
auto-calibration
process,
the
AM100
continues
to
search
for
the
best
phase
to
optimize
the
image
quality.
The
output
image
may
display
some
jitter
and
blurring
during
the
auto-calibration
process,
and
the
image
will
become
crisp
and
sharp
once
the
optimum
phase
is
found.
User
can
change
the
sampling
clock
phase
value
by
the
external
CPU.
The
phase
calibration
process
can
be
delayed
and
even
disabled
by
the
external
CPU
if
system
designer
wants
to
have
his/her
own
implementation.
The
phase
calibration
can
be
independently
turned
ON
or
OFF
by
external
CPU.
When
the
calibration
is
turned
OFF,
external
CPU
can
change
the
input
mode
and
frequency
definitions.
.
Page 16
(Confidential Do Not Copy,

ViewSonic
Service
Manual
April
1999
-
Version
1.0
VG150
THEORY
OF
CIRCUIT
OPERATION
Image Scaling
The
AM100
supports
several
different
input
modes,
and
the
input
image
may
have
different
sizes.
It
is
essential
to
support
automatic
image
scaling
so
that
the
input
image
is
always
displayed
to
the
full
screen
regardless
the
input
mode.
The
AM100
scale
the
images
in
both
horizontal
and
vertical
directions.
It
calculates
the
correct
scaling
ratio
for
both
directions
based
upon
the
LCD
panel
resolution,
and
the
input
mode
and
timing
information
produced
by
the
input
mode
detection
&
auto
calibration
function.
The
scaling
ratio
is
re-adjusted
whenever
a
different
input
mode
is
detected.
The
ratio
is
then
fed
to
the
buffer
memory
read
control
logic
to
fetch
the
image
data
with
the
right
sequence
and
timing.
Some
of
the
image
data
may
be
read
more
than
once
to
achieve
scaling
effect.
Image Interpolation
The
AM100
supports
image
interpolation
to
achieve
better
image
quality.
A
basic
image
scaling
algorithm
replicates
the
input
images
to
achieve
the
scaling
effect.
The
replication
scheme
usually
results
in
a
poor
image
quality.
The
AM100
implements
both
bi-linear
interpolation
and
a
proprietary
programmable
interpolation
algorithm.
The
programmable
interpolation
is
implemented
with
a
256-entry
mapping
table
in
the
EEPROM
to
allow
system
user
to
adjust
the
bi-
linear
interpolation
parameters
to
control
the
sharpness
and
smoothness
quality
of
the
image.
In
the
default
setting,
the
mapping
table
contains
s
Straight
line
of
slope
equal
to
1,
i.e.
the
data
in
entry
N
equal
to
the
value
N.
if
the
mapping
table
contains
a
line
of
slope
equal
to
2,
then
the
output
image
will
be
a
bit
sharper
than
image
generated
by
a
table
with
the
default
setting.
Dithering
The
AM100
supports
16.7
million
true
colors
for
6-bit
panel.
Two
dithering
algorithms
are
implemented
and
again
users
can
chose
between
them
through
the
external
micro-controller.
The
first
one
is
area-based
dithering,
and
the
second
one
is
a
ffame-based
frame
modulation,
or
called
frame
rate
control.
Through
external
micro-controller,
users
can
choose
among
different
dithering
algorithm.
OSD
mixer
and
LCD
interface
At
the
output
stage,
the
AM100
performs
the
OSD
mixer
function,
and
then
generates
24-bit
/
48
bit
RGB
signal
to
the
LCD
panel
with
the
correct
timing.
Page 17
iContidential Do Not Copy