ViewSonic ViewPanel VA520 User manual

Model No. VLCDS27996-1W
15” Color TFT LCD Display
Service Manual
ViewSonic VA521
ViewSonic
381 Brea Canyon Road, Walnut, California 91789 USA - [phone]
(VA521/VE510b/s-2_SM_819_1c Rev. 1cOct.2004)
VE510b/s-21
Model No. VLCDS27996-2W/-3W

Copyright
Copyright
¤
2004by ViewSonic Corporation. All rights reserved. No partof 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.
Optiquest is a registered trademark of ViewSonic Corporation.
Revision History
Revision Date Description Of Changes Approval
i
ViewSonic CorporationConfidential
-
Do Not Copy
1a 02/11/04 Initial Release DCN-4207 Angela Luh
DCN Number ECR Number
Documents Number Description of Changes EditorRevision SM Editing Date
1a 02/11/04 4207 Initial Release A. Lu
1b
04/05/04 4280 Add VE510b/s-2 A. Lu
4701
1c 10/25/04 4777 Change Scaler from MST P/N: 2365929596 A. Lu
To RealTek 2013 P/N: 2365930996 A. Lu
VA521
VE510b/s-2

TABLE OF CONTENTS
2. Specification
3. Front Panel Function Control Description
4. Circuit Description
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
11. PCB Layout Diagrams
1
2
5
10
16
17
19
35
44
45
51
6. Trouble Shooting Flow Chart
ii
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

This monitor is manufactured and tested on a ground principle that a user's safety comes first. However, improper
WARNINGS before installing and keep this guide handy.
WARNINGS
.This monitor should be operated only at the correct power sources indicated on the label on the rear end of the monitor.
If you're unsure of the power supply in your residence, consult your local dealer or power company.
.Do not try to repair the monitor your self as it contains no user-serviceable parts. This monitor should only be
repaired by a qualified technician.
.Do not remove the monitor cabinet. There are high-voltage parts inside that may cause electric shock to human
bodies, even when the power cord is unplugged.
.Stop using the monitor if the cabinet is damaged. Have it checked by a service technician.
.Put your monitor only in a clean, dry environment. If it gets wet, unplug the power cable immediately and
consult your service technician.
.Always unplug the monitor before cleaning it. Clean the cabinet with a soft, dry cloth. Apply non-ammonia
based cleaner onto the cloth, not directly onto the glass screen.
.Keep the monitor away from magnetic objects, motors, TV sets, and transformer.
.Do not place heavy objects on the monitor or power cord.
1.2 PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in this chassis have special safety visual inspections and the protection
afforded by them cannot necessarily be obtained by using replacement components rated for higher voltages,
wattage, etc. Before replacing any of these components read the parts list in this manual carefully. The use of
substitute replacement parts which do not have the same safety characteristics as specified in the parts list may
create shock, fire, or other hazards.
1. Precautions and Safety Notices
1.1 SAFETY PRECAUTIONS
use or installation may cause damage to the monitor as well as to the user. Carefully go over the following
1.3 SERVICE NOTES
.When replacing parts or circuit boards, clamp the lead wires around terminals before soldering.
.When replacing a high wattage resistor (more than 1W of metal oxide film resistor) in circuit board, keep the
resistor about 5mm away from circuit board.
.Keep wires away from high voltage, high temperature components and sharp edges.
.Keep wires in their original position so as to reduce interference.
.For usage of this product please also refer to the user's manual.
1
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

2.1. PRODUCT SPECIFICATION
LCD Panel 15.0" TFT
Power Management Energy Star compliant VESA
DPMS compatible
< 1W
Displayable Resolution XGA 1024× 768 (max.)
Pixel Dimension 0.297× 0.297mm
LCD Display Color 16.2M Color Max. (8bit)
Viewing Angle CR≧10
Horizontal: -60°~+60°
Vertical: -55°~+45°
Tilt +20°~ 0°
Contrast Ratio 300: 1 (min.)
400 : 1 (typ.)
Brightness 200 cd/m2 (min.)
250 cd/m2 (typ.)
Response Time Tr: 9 ms Tf: 16ms (typ.)
Active Display Area 304.1mm× 228.1mm
Temperature Operating: 0°C ~ +35°C
Storage: -20°C ~ +60°C
Power Input Voltage: 100~240 Vac
Consumption: 30 Watts (Max.)
2.2. SUPPORTING TIMING CHART
ITEM 1 2 3 4 5
TIMING 640×350@70Hz 640×480@60Hz 640×480@67Hz 640×480@75Hz 640×480@72Hz
Pixel Rate 25.175MHz 25.175MHz 30.240MHz 31.500MHz 31.500MHz
H TOTAL 31.778us 31.778us 28.571us 26.667us 26.413us
H DISPLAY 25.422us 25.422us 21.164us 20.317us 20.317us
H B-Porch 1.907us 1.907us 3.175us 3.810us 4.063us
H Width 3.813us 3.813us 2.116us 2.032us 0.270us
H Border 0.318us 0.318us 0.000us 0.000us 0.000us
V TOTAL 14.268ms 16.683ms 15.000ms 13.334ms 13.734ms
V DISPLAY 11.122ms 15.253ms 13.714ms 12.800ms 12.678ms
V B-Porch 1.907ms 1.049ms 1.114ms 0.427ms 0.528ms
Vs Width 0.064ms 0.064ms 0.086ms 0.080ms 0.079ms
V Border 0.191ms 0.254ms 0.000ms 0.000ms 0.000ms
2. Specification
H/V Sync +/- -/- -/- -/- -/-
Interlace No. No. No. No. No.
2
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

ITEM 6 7 8 9 10
TIMING 640×480@85Hz 720×400@70Hz 800×600@56Hz 800×600@60Hz 800×600@72Hz
Pixel Rate 36.000MHz 28.322MHz 36.000MHz 40.000MHz 50.000MHz
H TOTAL 22.111us 31.778us 28.444us 26.400us 20.800us
H DISPLAY 17.778us 25.422us 22.222us 20.000us 16.000us
H B-Porch 2.222us 1.907us 3.556us 2.200us 1.280us
H Width 1.556us 3.813us 2.000us 3.200us 2.400us
H Border 0.000us 0.318us 0.000us 0.000us 0.000us
V TOTAL 11.764ms 14.268ms 17.778ms 16.579ms 13.853ms
V DISPLAY 11.093ms 12.711ms 17.066ms 15.840ms 12.480ms
V B-Porch 0.578ms 1.112ms 0.626ms 0.607ms 0.478ms
Vs Width 0.069ms 0.064ms 0.057ms 0.106ms 0.125ms
V Border 0.000ms 0.222ms 0.000ms 0.000ms 0.000ms
H/V Sync -/- -/+ +/+ +/+ +/+
Interlace No. No. No. No. No.
ITEM 11 12 13 14 15
TIMING 800×600@75Hz 800×600@85Hz 832×[email protected] 1024×768@60Hz 1024×768@70Hz
Pixel Rate 48.500MHz 56.250MHz 57.280MHz 65.000MHz 75.000MHz
H TOTAL 21.333us 18.631us 20.112us 20.677us 17.707us
H DISPLAY 16.162us 14.222us 14.525us 15.754us 13.653us
H B-Porch 3.232us 2.702us 3.771us 2.462us 1.920us
H Width 1.616us 1.138us 1.118us 2.092us 1.813us
H Border 0.000us 0.000us 0.000us 0.000us 0.000us
V TOTAL 13.333ms 11.756ms 13.417ms 16.666ms 14.272ms
V DISPLAY 12.800ms 11.179ms 12.552ms 15.880ms 13.599ms
V B-Porch 0.448ms 0.503ms 0.784ms 0.600ms 0.513ms
Vs Width 0.064ms 0.056ms 0.060ms 0.124ms 0.106ms
V Border 0.000ms 0.000ms 0.00ms 0.000ms 0.000ms
H/V Sync +/+ +/+ -/- -/- -/-
Interlace No. No. No. No. No.
ITEM 16 17
TIMING 1024×768@72Hz 1024×768@75Hz
Pixel Rate 77.066MHz 78.750MHz
H TOTAL 17.232us 16.660us
H DISPLAY 13.287us 13.003us
3
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

H B-Porch 1.869us 2.235us
H Width 1.765us 1.219us
H Border 0.000us 0.000us
V TOTAL 13.889ms 13.328ms
V DISPLAY 13.234ms 12.795ms
V B-Porch 0.500ms 0.466ms
Vs Width 0.103ms 0.050ms
V Border 0.000ms 0.000ms
H/V Sync -/- +/+
Interlace No. No.
2.3. D-SUB CONNECTOR
D-SUB 15 PIN CONNECTOR
1.Red Video 6.Red GND 11.NC
2.Green Video 7.Green GND 12.SDA
3.Blue Video 8.Blue GND 13.H-sync
4.NC 9. +5V for DDC 14.V-sync
5.GND 10.GND 15.SCL
12345
678910
11 12 13 14 15
SIGNAL LEVEL
CONNECTOR SIGNAL DESCRIPTION
R RED 0.7vp-p(VIDEO)
G GREEN 0.7vp-p(VIDEO)
B BLUE 0.7vp-p(VIDEO)
H H/SYNC TTL positive or negative
V V/SYNC TTL positive or negative
SDA DDC1/2B TTL
SCL DDC1/2B TTL
4
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

Scroll through menu
options and adjust the
displayed control.
Displays, saves
changes to, and exits
the Main Menu.
Power On/Off
Selects a highlighted control. Also,
displays the control screen for the
selected control and toggles
between control pairs.
Power light
Front Control Panel
Main Menu
with OnView controls
3. Front Panel Function Control Description
5
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

. (The black border around the
edge of the screen should barely touch the illuminated “active area” of the
LCD display.)
The line at the
bottom of the
screen tells you
what you can do
next: Exit or Select
the control that is
highlighted.
Main Menu
1:EXIT 2:SELECT
Auto Adjust
Contrast/Brightness
Color Adjust
Information
Image Adjust
Setup Menu
Memory Recall
AUTO
SET
i
?
Do the following to adjust the screen image:
.Todisplay the Main Menu, press button [1].
Toadjust the control, press the up Ior down Jbuttons.
Tosave the adjustments and exit the menu, press button [1] twice.
The following tips may help you optimize your display:
•
Adjust your computer's graphic card so that it outputs a video signal 1024 x
768 @ 60 Hz to the LCD display.(Look for instructions on“changing the
refresh rate” in your graphic card's user guide.)
•If necessary, make small adjustments using H. POSITION and V. POSITION
until the screen image is completely visible
NOTE: All OnView menus and adjustment screens disappear automatically
after about 15 seconds. This time period is adjustable through the Setup
menu and the OSD timeout control described on page 11.
Toselect the highlighted control, press button [2]. A control screen appears
like the example shown below.
Contrast
1:EXIT 2: Brightness
Tohighlight a control you want to adjust, press Ior Jto scroll up or down
the Main Menu.
.
.
.
.
6
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

Main Menu Controls
Adjust the menu items shown below byusing the up Iand down Jbuttons.
ControExplanation
Auto Adjustautomatically sizes, centers, and fine tunes the
videosignal to eliminate waviness and distortion.
Press the [2] button to obtain a sharper image.
NOTE:Auto Adjust works with most common video cards. If
this function does not work on your LCD display, then lower the
video refresh rate to 60 Hz and set the resolution to its pre-set
value.
Contrast adjusts the difference between the image background
(black level) and the foreground (white level).
Brightness adjusts background black level of the screen image.
Color Adjust provides several color options: preset color
temperatures and User which allows you to adjust red (R), green
(G), and blue (B). The factory setting for this product is 6500K
(6500 Kelvin).
9300K — Adds blue to the screen image for cooler white (used
in most office settings with fluorescent lighting).
6500K — Adds red to the screen image for warmer white and
richer red.
5400K — Adds green to the screen image for a darker color.
sRGB
—sRGB is quickly becoming the industry standard for
color management, with support being included in many of the
latest applications. Enabling this setting allows the LCD display
to more accurately display colors the way they were originally
intended. Enabling the sRGB setting will cause the Contrast and
Brightness adjustments to be disabled.
User Color — Individual adjustments for red (R), green (G),
and blue (B).
1
To select color (R, G or B) press button [2].
2
To adjust selected color, press
▲
or
▼
.
Important: Ifyou selectRECALL from the MainMenuwhen
the product is set to a Preset Timing Mode, colors return to the
6500K factory preset.
Information
displays the timing mode (video signal input)
coming from the graphics card in your computer. See your
graphic card’s user guide for instructions on changing the
resolution and refresh rate (vertical frequency).
i
7
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

VESA 1024 x 768 @ 60 Hz (recommended) means that the
resolution is 1024 x 768 and the refresh rate is 60 Hertz.
H. Size (Horizontal Size) adjusts the width of the screen image.
NOTE: Vertical size is automatic with your LCD display.
H./V. Position adjusts horizontal and vertical position of the
screen image. You can toggle between Horizontal and Vertical
by pressing button [2]. Horizontal moves the screen image to
the left or to the right. Vertical moves the screen image up and
down.
Information
1:EXIT
H. Frequency: 48.60 KHz
V. Frequency: 60.00 Hz
Pixel Clock: 65.00 MHz
Resolution: 1024 x 768
Model Number: VLCDS23585-2W
Serial No:
www.viewsonic.com
Image Adjust
The Image Adjust controls are explained below:
Image Adjust
1:EXIT 2:SELECT
H./V. Position
H. Size
Fine Tune
Sharpness
Fine Tunesharpens focus by aligning the illuminated text and/
or graphic characters.
NOTE:TrytheAuto Adjustbefore using the Fine
Tune control.
Sharpnessadjusts the clarity and focus of the screen image.
Setup Menu displays the menu shown below.
Setup Menu
1:EXIT 2:SELECT
Language Select
Resolution Notifier
OSD Position
OSD Timeout
OSD
The Setup Menu controls are explained below.
?
8
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

Resolution Notice
For best picture quality
change the resolution to
1024 x 768
1:EXIT 2:DISABLE
the menus and control screens.
OSD Position allows you to move the on-screen display menus
and control screens.
OSD Timeoutsets the length of time an on-screen display
screen is displayed. For example, with a “15 second” setting, if
a control is not pushed within 15 seconds, the display screen
disappears.
Resolution Notice advises the optimal resolution to use.
LanguageSelectallowsyoutochoosethelanguageusedin
OSD
Memory Recallreturns adjustments to the original factory
settings if the display is operating in a factory Preset Timing
Mode listed in this user guide.
Short Cut Key
Function Key : 5 Keys !
!!
!1 2 ▼
▼▼
▼
▲ ▲▲
▲
[1] Main Menu
[2] Auto Image Adjust
[▼
▼▼
▼] or [▲
▲▲
▲]to immediately activate Contrast menu.
It should be change to Brightness OSD
by push button [2].
[▼
▼▼
▼] + [▲
▲▲
▲] recall Contrast or Brightness while in
the Contrast or Brightness adjustment,
or recall both of Contrast and
Brightness when the OSD is not open.
[1] + [2] toggle 720x400 and 640x400 mode when
input 720x400 or 640x400 mode.
[1] + [▼
▼▼
▼] + [▲
▲▲
▲]
(Keep pushing 5 sec)
White Balance.
[1] + [▼
▼▼
▼] Power Lock
[1] + [▲
▲▲
▲] OSD Lock
9
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

(VA521/VE510s-2/VE510b-2 Realtek Scaler)
A. AC-DC CONVERTER
The power supply with a high-integrated green-mode PWM controller provides several features to enhance the
performance of power flyback converters.
I801 is a PWM controller and provides many protection functions.
I802 is a photo couple to transfer the feedback signal from the second side which I803 detected both of the output
DC voltage on 3.3V and 12V.
D813 detected the working voltage on I801 and Q805 would pull down the voltage on I801 pin5 to shut down
I801 if feedback loop was failed.
R826 would be a dynamic load which was active while backlight was turned off and system still working on, this
kept 12V output voltage under 13V to protect the panel. After system went to power saving mode, the R826
would no loaded. This was detected by I804 and Q803 active the R826 to load or not.
B. Scaling controller
The RTD2013 ADC is to convert RGB analog signal to digital signal that scaling chip can acknowledge.
The HSYNC input receives a logic signal and provides the frequency reference for pixel clock generation.
The scaling IC is to converts the input signal ranging from VGA to XGA into XGA resolution that panel can
acknowledge.
General
 Embedded dual DDC support DDC1, DDC2B,DDC/CI
 Zoom scaling up and down
 Embedded Pattern Generator
 No external memory required.
 Require only one crystal to generate all timing
 Embedded reset control output
 Embedded crystal output to MICROP
 3 channels 8 bits PWMoutput, andselectablePWM clock frequency.
PIN DESCRIPTION
(I/O Legend: A= Analog, I= Input, O=Output, P=Power, G=Ground)
■ ADC: 15 pins
Name I/O Pin No Description Note
ADC_ GND AG 27 ADC ground
ADC_REFIO AP 28 ADC band-gap voltage de-coupling 1.20V
ADC_VDD AP 29 Analog power (3.3V)
BLUE+ AI 30 Analog input from BLUE channel
BLUE- AI 31 Analog input ground from BLUE channel
ADC_ GND AG 32 ADC ground
SOG/ADC_TEST AIO 33 SOG in/ADC test pin
GREEN+ AI 34 Analog input from GREEN channel
GREEN- AI 35 Analog input ground from GREEN channel
ADCB_VDD AP 36 Analog power (3.3V)
RED+ AI 37 Analog input from RED channel
RED_ AI 38 Analog input ground from RED channel
ADC_GND AG 39 Analog ground
ADC_GND AG 40 Analog ground
ADC_VDD AP 41 Analog power (3.3V)
AHS AI 42 Analog HS input (10), (4), (5)
AVS AI 43 Analog VS input (2), (4), (5)
4. Circuit Description
10
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

■PLL:8 pins
Name I/O Pin No Description Note
XO AI 1 Reference clock output
XI AO 2 Reference clock input
DPLL GND AG 3 Ground for digital PLL
DPLL VDD AP 4 Power for digital PLL (3.3V)
APLL VDD AP 5 Power for multi-phase PLL (3.3V)
PLL TEST1 AIO 6 Test Pin 1 / IRQ# 3.3V tolerance
PLL TEST2 AIO 7 Test Pin 2/Power-on-latch for crystal out
Frequency
APLL GND AG 8 Ground for multi-phase PLL
■Control Interface: 7 pins
Name I/O Pin No Description Note
SDIO [0] IO 54 Serial control I/F data in/Parallel port data
[0] (2), (3), / 2mA
SDIO [1] / TCON [4] /
BBLU [0] IO 53 Parallel port data [1] / TCON [4] / TTL BBLU [0] (1), (2), (3), / 2mA
SDIO [2] / TCON [3] /
BBLU [1] IO 52 Parallel port data [1] / TCON [3] / TTL BBLU [1] (1), (2), (3), / 2mA
SDIO [3] / PWM2 /
TCON [2] IO 51 Parallel port data [1] / TCON [4] / PWM2 (1), (2), (3), / 2mA
SCLK I 50 Serial control I/F clock (2), (3), (5)
SCSB I 111 Serial control I/F chip select (2), (3), (5)
RESET O 56 RESET output for Micron (2), (5), (6) / 2mA
■ Display & TCON/VIDEO-8 Port: 54 pins
:LVDS+RSDS+TTLO :RSDS+TTLO :RSDS+TTLIO :TTLO :TTLIO
Pin
NO 6-bits Dual
RSDS 6-bits Single RSDS 8/6 bits Dual/Single
LVDS
8 bits
Dual/Single
TTL
6 bits Dual
TTL 6 bits Single TTL Note
51 S [3] /
TCON [2] /
PWM2
S 3] /
TCON [2] /
PWM2
S [3] /
TCON [2] /
PWM2
S [3] /
TCON [2] /
PWM2
S [3] /
TCON [2] /
PWM2
S [3] /
TCON [2] /
PWM2
(1), (2), (3), /
2mA
52 S [2] /
TCON [3] S [2] / TCON [3] S [2] / TCON [3] S [2] / BBLU [1] /
TCON [3]
S [2] /
TCON [3] S [2] / TCON [3] (1), (2), (3), / 2mA
53 S [1] /
TCON [4] S [1] / TCON [4] S [1] / TCON [4] S [1] / BBLU [0] /
TCON [4]
S [1] /
TCON [4] S [1] / TCON [4] (1), (2), (3), / 2mA
55 PWM2 /
COUT /
TCON [13]
PWM2 /
COUT /
TCON [13]
PWM2 /
COUT /
TCON [13]
PWM2 /
COUT /
TCON [13]
PWM2 /
COUT /
TCON [13]
PWM2 /
COUT /
TCON [13]
(1), (2), (3), /
2mA
59 BB3P BB3P NC BBLU [7] BBLU [7] BBLU [7]
60 BB3N BB3N NC BBLU [6] BBLU [6] BBLU [6]
61 BB2P BB2P NC BBLU [5] BBLU [5] BBLU [5]
62 BB2N BB2N NC BBLU [4] BBLU [4] BBLU [4]
63 BB1P BB1P NC BBLU [3]
/T0 BBLU [3] BBLU [3]
64 BB1N BB1N NC BBLU [2]
/T1 BBLU [2] BBLU [2]
65 BCLKP BCLKP NC BGRN [1] /
T2 TCON [6] TCON [6]
66 BCLKN BCLKN NC BGRN [0] /
T3 TCON [5] TCON [5]
67 BG3P BG3P NC BGRN [7] BGRN [7] BGRN [7]
68 BG3N BG3N NC BGRN [6] BGRN [6] BGRN [6]
11
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

73 BG2P BG2P TODP BGRN [5] /
T4 BGRN [5] BGRN [5]
74 BG2N BG2N TODN BGRN [4] /
T5 BGRN [4] BGRN [4]
75 BG1P BG1P TOCLKP BGRN [3] /
T6 BGRN [3] BGRN [3]
76 BG1N BG1N TOCLKN BGRN [2] /
T7 BGRN [2] BGRN [2]
77 BR3P BR3P TOCP BRED [7] /
T8 BRED [7] BRED [7]
78 BR3N BR3N TOCN BRED [6] /
T9 BRED [6] BRED [6]
79 BR2P BR2P TOBP BRED [5] /
T10 BRED [5] BRED [5]
80 BR2N BR2N TOBP BRED [4] /
T11 BRED [4] BRED [4]
81 BR1P BR1P TOAP BRED [3] /
T12 BRED [3] BRED [3]
82 BR1N BR1N TOAP BRED [2] /
T13 BRED [2] BRED [2]
85 AB3P NC TEDP ABLU [7] /
T14 ABLU [7] ABLU [7]
86 AB3N NC TEDN ABLU [6] /
T15 ABLU [6] ABLU [6]
87 AB2P NC TECLKP ABLU [5] /
T16 ABLU [5] ABLU [5]
88 AB2N NC TECLKN ABLU [4] /
T17 ABLU [4] ABLU [4]
89 AB1P NC TECP ABLU [3] /
T18 ABLU [3] ABLU [3]
90 BB1N NC TECN ABLU [2] /
T19 ABLU [2] ABLU [2]
91 ACLKP NC TEBP ABLU [1] /
T20 TCON [1] TCON [1]
92 ACLKN NC TEBN ABLU [0] /
T21 TCON [0] TCON [0]
93 AG3P NC TEAP AGRN [7] /
T22 AGRN [7] AGRN [7]
94 AG3N NC TEAN AGRN [6] /
T23 AGRN [6] AGRN [6]
99 AG2P TCON [11] NC AGRN [5] /
T24 AGRN [5] AGRN [5]
100 AG2N TCON [10] NC AGRN [4] /
T25 AGRN [4] AGRN [4]
101 AG1P TCON [9] NC AGRN [3] /
T26 AGRN [3] AGRN [3]
102 AG1N TCON [8] NC AGRN [2] /
T27 AGRN [2] AGRN [2]
103 AR3P TCON [7] NC ARED [7] /
T28 ARED [7] ARED [7]
104 AR3N TCON [6] NC ARED [6] /
T29 ARED [6] ARED [6]
105 AR2P TCON [5] NC ARED [5] /
TH ARED [5] ARED [5]
106 AR2N TCON [1] NC ARED [4] /
TV ARED [4] ARED [4]
107 AR1P TCON [0] NC ARED [3] /
TE ARED [3] ARED [3]
12
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

108 AR1N NC NC ARED [2] /
TK ARED [2] ARED [2]
113 PWM2 /
COUT /
TCON [12]
PWM2 /
COUT /
TCON [12]
PWM2 /
COUT /
TCON [12]
ARED [1] COUT PWM2 /
COUT /
TCON [12]
(9)
114 TCON [11]
/V [0] V [0] V [0] ARED [0] TCON [11] (1), (7), (8)
115 TCON [10]
/V [1] V [1] V [1] BRED [1] TCON [10] (1), (7), (8)
116 TCON [9] /
V [2] V [2] V [2] BRED [0] TCON [9] (1), (7), (8)
117 TCON [8] /
V [3] V [3] V [3] AGRN [1] TCON [8] (1), (7), (8)
118 TCON [7] /
V [4] V [4] V [4] AGRN [0] TCON [7] (1), (7), (8)
119 TCON [6] /
V [5] V [5] V [5] DHS DHS DHS (1), (7), (8)
122 TCON [5] /
V [6] V [6] V [6] DVS DVS DVS (1), (7), (8)
123 TCON [1] /
V [7] V [7] V [7] DENA DENA DENA (1), (7), (8)
124 TCON [0] /
VCLK VCLK VCLK DCLK DCLK DCLK (1), (7), (8)
*Single RSDS, even/odd swap, data (59~82) output to pin85~108, TCON (99~108) output to pin59~68.
*In 6-bit dual TTL output mode, Video8 cannot output TCON7~TCON11; while video8 can output TCON in
6-bit single TTL mode.
■ TMDS: 18 pins
Name I/O Pin No Description Note
TMDS_TST/ PWM1 AIO 9 TMDS_TEST Pin / PWM1 / Power-on-latch
for serial / parallel port
TMDS_GND G 10
TMDS_VDD P 11 (3.3V)
NC A 12 Impedance Match Reference.
TMDS_VDD P 13 (3.3V)
NC I 14 Differential Data Input
NC I 15 Differential Data Input
TMDS_GND G 16
NC I 17 Differential Data Input
NC I 18 Differential Data Input
TMDS_VDD P 19 (3.3V)
NC I 20 Differential Data Input
NC I 21 Differential Data Input
TMDS_GND G 22
NC I 23 Differential Data Input
NC I 24 Differential Data Input
TMDS_GND G 25
TMDS_VDD P 26 (3.3V)
■ PWM Interface: (PWM1, PWM2 can be selected from 1 of 3 possible pins.)
Name I/O Pin No Description Note
PWM2 / TCON [2] / S
[3] O 51 PWM2 / TCON [2] / SDIO [3] (1), (2), (3), (5), (8),
PWM2 / TCON [13] /
COUT O 55 PWM2 / TCON [13] / Crystal out (2), (8), (9)
PWM2 / TCON [12] /
COUT O 113 PWM2 / TCON [12] / Crystal out (2), (8), (9) 6bit dual TTL cannot
support
13
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

PWM1 / TMDS_TST AIO 9 PWM1/ TMDS_TEST Pin/ Power-on-latch
for serial / parallel port (2), (7), (8)
PWM1 / DDCSDA /
TCON [1] / BBLU [0] IO 47 PWM1 / DDC serial control I/F data input / output / TCON [4] (1), (2), (3), (5), (8),
PWM1 / TCON [7] IO 125 PWM1 / TCON [7] (1), (2), (3), (5),
(8),
PWM0 / REFCLK IO 112 PWM0 / (In / out) test pin for DCLK /
Video8 even-odd signal (2), (9)
■ DDC Channel:4 pins
Name I/O Pin No Description Note
DDCSCL/TCON [0] /
BBLU [1] I 46 DDC serial control I/F clock/TCON [0]/TTL
BBLU [1] (2), (3), (5)
DDCSDA/TCON [1] /
PWM1/BBLU [0] IO 47 DDC serial control I/F data input/ output/
TCON [1]/ PWM1/ TTL BBLU [0] (1), (2), (3), (5), (6), (8)/8mA/no
slew
TCON [5] I 126 TCON [5] (2), (3), (5)
TCON [7]/PWM1 IO 125 TCON [7]/ PWM1 (1), (2), (3), (5),
(6), (8)/8mA/no
slew
■ Power & Ground:22 pins
Name I/O Pin No Description
3.3V Power P 49,121 VCCIO: 2
3.3V Ground G 48,120 GNDIO: 2
3.3V Power P 58,71,83, 95,110 PVCC: 5
3.3V Ground G 57,72,84,96,109 PGND: 5
2.5V Power P 45,69,98,127 VCCK: 4
2.5V Ground G 44,70,97,128 GNDK: 4
Note: (1) TTL compatible CMOS Input (Vt=1.7V); VCC=3.3V;
(2) 5V tolerance pad;
(3) Internal 75K Ohms pull high resistor.
(4) Internal 75K Ohms pull low resistor.
(5) Schmitt trigger CMOS Input (Vt=1.4~2.2V);
(6) Open-Drain, Output Drive low & Pull-high.
(7) Bi-directional input/output
(8) Programmable driving current (2~10mA)
(9) TTL output 5V & 3.3V
(10) 4V tolerance pad
14
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

In 3.3V power system, the VDD and VDD3 are connected to 3.3V power, all output pins swing from 0~3.3V,
HSYNC, VSYNC and open drain pin can accept 0~5V input range, other pins must be kept below 3.3V. And the
ADC conversion range is 3.3V.
D. INVERTER
In order to drive the CCFLs embedded in the panel module, there is a push-pull inverter to convert by the
controller.
from input 12V up to hundreds ofAC voltage output peak to peak.
The inverter is formed by symmetric in order to drive the separate lamp modules.
The input stage consists of a PWM controller, push-pull inverter, and switching MOSFET to convert DC input
into AC output.
The output stage consists of a tuning capacitor, transformer, and push-pull MOSFET pair to boost AC output up
to hundreds of voltage peak to peak.
And one resister is serial to lamp for output voltage feedback.
There are two signals which control the inverter come from system to turn on the inverter and control brightness.
Logic “low” level which send to I901 is turn on the inverter.
BRI signal control brightness by DC level which was integral from PWM signal.
POWER CONFIGURATION
The MTV312M can work on 5V or 3.3V power supply system.
In 5V power system, the VDD pin is connected to 5V power and the VDD3 needs an external capacitor, all
output pins can swing from 0~5V, input pins can accept 0~5V input range.
And ADC conversion range is 5V. However, X1 and X2 pins must be kept below 3.3V.
C. MTV312M64
The MTV312M micro-controller is an 8051 CPU core embedded device especially tailored for CRT/LCD
Monitor applications. It includes an 8051 CPU core, 1024-byte SRAM, 14 built-in PWM DACs, VESA DDC
interface, 4-channelA/D converter, and a 64K-byte internal program Flash-ROM.
A “CMOS output pin” means it can sink and drive at least 4mA current. It is not recommended to use such
pin as input function.
A “open drain pin” means it can sink at least 4mAcurrent but only drive 10~20uA to VDD. It can be used as
input or output function and needs an external pull up resistor.
A “8051 standard pin” is a pseudo open drain pin. It can sink at least 4mA current when output is at low level,
and drives at least 4mA current for 160nS when output transits from low to high, then keeps driving at 100uA to
maintain the pin at high level. It can be used as input or output function. It needs an external pull up resistor when
driving heavy load device.
15
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

5.1. ADJUSTMENT CONDITIONS AND PRECAUTIONS
1. Approximately 30 minutes should be allowed for warm up before proceeding.
2. Adjustments should be undertaken only on those necessary elements since most of them have been carefully
preset at the factory.
3. ESD protection is needed before adjustment.
5.2. MAIN ADJUSTMENTS
NO. FUNCTION DESIGNATION
1. V-com Voltage On the back of the Panel
2. Eeprom Initial Function Key
3. White Balance Function Key
5.3. ALIGNMENT PROCEDURES
Adjustment Conditions and Precautions:
(A). Power supply voltage:
AC 110/120V±10% 60 Hz±5%, AC 220/240V±10% 50 Hz ±5%.
(B). Warm up time:
The display must be power ON for at least 30 minutes at full white pattern before starting alignments.
This is especially critical in color temperature and white balance adjustments.
(C). Signals: reference the front detail specifications and timing table.
Video : reference the front detail specifications.
1. Adjustment of V-com Voltage:
A. Timing : 1024x768@60Hz. 48KHz
B. Pattern : The picture of “ Shut down windows” or Full screen pixel ON/OFF pattern.
C. Adjust V-com to let the center of the screen no flash.
2. Eeprom Initial:
A. Timing : 1024x768@60Hz.
B. Pattern : Cross hatch.
C. Switch off the power and press the “▲” and “ 2 “ key simultaneously, then switch on the power. At
this time we can enter into the factory mode when press the “ 1 “key.
D. Select the “EEPROM INIT” item and press “ 2 “key to reset the Eeprom.
3. White Balance Adjustment :
A. Timing : 1024x768@60Hz.
B. Pattern : 16Gray Level. or 5-MOSAIC (Pattern 42)
C. Set CA210 color analizer at the center of screen and along a perpendicular to the screen at 0cm from
the display.
D. Move “▼” key to select the “ WHITE BALANCE” item in the factory mode and press “ 2 “key,
then the white balance will be auto dadjusted.
E. Color temperature verification: (Set Brightness and Contrast to Maximum)
6500K verify : press “▼” ,“▲” key to move cursor to 6500K at factory mode
and press “ 2 “ key, and then check the color temperature is
x=0.313 ±0.02
y=0.329 ±0.02
Y≧200 cd/m2
5. Adjusting Procedure
16
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2

(VA521/VE510s-2/VE510b-2)
6.1. NO POWER or BACKLIGHT
NO POWER
3.3V on P801
pin5,6 to GND
12V on P802
pin3 to GND
NO BACKLIGHT.
Check P802 pin2 with
3.3V or not
CHECK C805
with voltage more than
150volts or not
Check R813~R815 broken or
not
No
With power
but power saving mode more
than 1 Watts
Check Q903,I804
without connecting main board,
with main board more than
1Watts
check main board.
Yes
CHECK
D801~D804 failed or not,
F801 broken or not,
R802 failed or not
Check main board
backlight_on signal
Check Q801 D & S short or
not,I801 failed,
R807 broken or not
Check Q802,D813 failed or not
If there had Sawtooth
waveform on DC output
Check I802,I803
If there had Sawtooth
waveform on DC output
Check D809,D811.
If there had Sawtooth
waveform on DC outputr
Check 5V on I901 pin6
Check I901 pin1 voltage
>1.0volts,<3.0volts
while inverter turn on
Check
Q901,Q902,D903,D904
Check Q903,D906
Check R925,F901
broken or not
Check Q905.
Check I901,I902,
R904,R905
Yes
Yes Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
17
ViewSonic CorporationConfidential
-
Do Not Copy VA521
VE510b/s-2
6. Trouble Shooting Flow Chart