Acer AL2251W User manual

Acer AL2251W
Service Guide
1

Service Guide Version and Revision
Version Release Date Revision History TPV model
A00 Sep-29-2006 Initial Release TC6MMADKWGAGACP
2

Copyright
Copyright © 2006by Acer Incorporated. 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 Acer Incorporated.
Disclaimer
The information in this guide is subject to change without notice. Acer Incorporated makes no representations or
warranties, either expressed or implied, with respect to the contents hereof and specifically disclaims any warranties
of merchantability or fitness for any particular purpose. Any Acer Incorporated software described in this manual is
sold or licensed "as is". Should the programs prove defective following their purchase, the buyer (and not Acer
Incorporated, its distributor, or its dealer) assumes the entire cost of all necessary servicing, repair, and any
incidental or consequential damages resulting from any defect in the software.
Intel is a registered trademark of Intel Corporation.
Pentium and Pentium II/III are trademarks of Intel Corporation.
Other brand and product names are trademarks and/or registered trademarks of their respective holders.
Trademarks
Acer is a registered trademark of Acer Incorporated.
All other trademarks are property of their respective owners.
Conventions
The following conventions are used in this manual:
Screen messages Denotes actual messages that appear on screen.
Note Gives bits and pieces of additional information related to the current topic.
Warning Alerts you to any damage that might result from doing or not doing specific
actions.
Caution Gives precautionary measures to avoid possible hardware or software
problems.
Important Remind you to do specific actions relevant to the accomplishment of
procedures.
3

Preface
Before using this information and the product it supports, please read the following general information.
1. This Service Guide provides you with all technical information relating to the BASIC CONFIGURATION decided
for Acer's "global" product offering. To better fit local market requirements and enhance product competitiveness,
your regional office may have decided to extend the functionality of a machine (e.g. add-on card, modem, or extra
memory capability). These LOCALIZED FEATURES will NOT be covered in this generic service guide. In such
cases, please contact your regional offices or the responsible personnel/channel to provide you with further
technical details.
2. Please note WHEN ORDERING FRU PARTS, that you should check the most up-to-date information available on
your regional web or channel. If, for whatever reason, a part number change is made, it will not be noted in the
printed Service Guide. For ACER-AUTHORIZED SERVICE PROVIDERS, your Acer office may have a
DIFFERENT part number code to those given in the FRU list of this printed Service Guide. You MUST use the list
provided by your regional Acer office to order FRU parts for repair and service of customer machines.
Warning: (For FCC Certified Models)
Note: This equipment has been tested and found to comply with the limits for 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 interference will not occur in a particular installation. If this equipment does cause harmful
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:
1. Reorient or relocate the receiving antenna.
2. Increase the separation between the equipment and receiver.
3. Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
4. Consult the dealer or an experienced radio/TV technician for help.
Notice:
1. The changes or modifications not expressly approved by the party responsible for compliance could void the
user's authority to operate the equipment.
2. Shielded interface cables and AC power cord, if any, must be used in order to comply with the emission limits.
3. The manufacturer is not responsible for any radio or TV interference caused by unauthorized modification to this
equipment. It is the responsibility of the user to correct such interference.
As ENERGY STAR®Partner our company has determined that this product meets the ENERGY STAR®
guidelines for energy efficiency.
Warning:
To prevent fire or shock hazard, do not expose the monitor to rain or moisture. Dangerous high voltages are
present inside the monitor. Do not open the cabinet. Refer servicing to qualified personnel only.
4

Precautions
zDo not use the monitor near water, e.g. near a bathtub, washbowl, kitchen sink, laundry tub, swimming pool or in
a wet basement.
zDo not place the monitor on an unstable trolley, stand, or table. If the monitor falls, it can injure a person and
cause serious damage to the appliance. Use only a trolley or stand recommended by the manufacturer or sold
with the monitor. If you mount the monitor on a wall or shelf, uses a mounting kit approved by the manufacturer
and follow the kit instructions.
zSlots and openings in the back and bottom of the cabinet are provided for ventilation. To ensure reliable
operation of the monitor and to protect it from overheating, be sure these openings are not blocked or covered.
Do not place the monitor on a bed, sofa, rug, or similar surface. Do not place the monitor near or over a radiator
or heat register. Do not place the monitor in a bookcase or cabinet unless proper ventilation is provided.
zThe monitor should be operated only from the type of power source indicated on the label. If you are not sure of
the type of power supplied to your home, consult your dealer or local power company.
zThe monitor is equipped with a three-pronged grounded plug, a plug with a third (grounding) pin. This plug will fit
only into a grounded power outlet as a safety feature. If your outlet does not accommodate the three-wire plug,
have an electrician install the correct outlet, or use an adapter to ground the appliance safely. Do not defeat the
safety purpose of the grounded plug.
zUnplug the unit during a lightning storm or when it will not be used for long periods of time. This will protect the
monitor from damage due to power surges.
zDo not overload power strips and extension cords. Overloading can result in fire or electric shock.
zNever push any object into the slot on the monitor cabinet. It could short circuit parts causing a fire or electric
shock. Never spill liquids on the monitor.
zDo not attempt to service the monitor yourself; opening or removing covers can expose you to dangerous
voltages and other hazards. Please refer all servicing to qualified service personnel
zTo ensure satisfactory operation, use the monitor only with UL listed computers which have appropriate
configured receptacles marked between 100 - 240V AC, Min. 5A.
zThe wall socket shall be installed near the equipment and shall be easily accessible.
Special Notes On LCD Monitors
The following symptoms are normal with LCD monitor and do not indicate a problem.
Notes
zDue to the nature of the fluorescent light, the screen may flicker during initial use. Turn off the Power Switch and
then turn it on again to make sure the flicker disappears.
zYou may find slightly uneven brightness on the screen depending on the desktop pattern you use.
zThe LCD screen has effective pixels of 99.99% or more. It may include blemishes of 0.01% or less such as a
missing pixel or a pixel lit all of the time.
zDue to the nature of the LCD screen, an afterimage of the previous screen may remain after switching the image,
when the same image is displayed for hours. In this case, the screen is recovered slowly by changing the image
or turning off the Power Switch for hours.
5

Table Of Contents
Chapter 1 Monitor Features ………………………………………… 6
Introduction ……………………………………… 7
Electrical Requirements ……………………………………… 8
LCD Monitor General Specification ……………………………………… 9
LCD Panel Specification ……………………………………… 11
Support Timing ……………………………………… 13
Monitor Block Diagram ……………………………………… 14
Main Board Diagram ……………………………………… 15
Software Flow chart ……………………………………… 16
Main Board Layout ……………………………………… 18
Front Bezel ……………………………………… 19
Rear Bezel ……………………………………… 20
Chapter 2 Operating Instructions ……………………………………… 21
External Controls ……………………………………… 21
Front Panel Controls ……………………………………… 22
Adjusting the picture ……………………………………… 23
Hot-Key Menu ……………………………………… 26
OSD Message ……………………………………… 26
LOGO ……………………………………… 27
Chapter 3 Machine Disassembly ……………………………………… 28
Chapter 4 Troubleshooting ……………………………………… 33
Chapter 5 Connector Information ……………………………………… 38
Chapter 6 FRU (Field Replacement Unit) List ……………………………………… 39
Exploded Diagram ……………………………………… 40
Chapter 7 Schematic Diagram ……………………………………… 43
6

Monitor Features
Cha
p
ter 1
Introduction
Scope
This specification defines the requirements for the 19” MICROPROCESSOR based Multi-mode supported high
resolution color LCD monitor. This monitor can be directly connected to general 15-pin D-sub VGA connector and
24-pin DVI connector, also supports VESA DPMS power management and plug & play function. There is a build-in
stereo audio amplifier with OSD control to drive a pair of speakers.
Description
The LCD monitor is designed with the latest LCD technology to provide a performance oriented product with no
radiation. This will alleviate the growing health concerns. It is also a space saving design, allowing more desktop
space, and comparing to the traditional CRT monitor, it consumes less power and gets less weight in addition MTBF
target is 50k hours or more.
Chart of AL2251W
Panel M220Z1-L01
D-Sub 15-pin
Signal Interface DVI 24-pin
Sync Type Separate / Compatible
Color Temp User Adjust Support
DDC DDC2B
Speaker 1.5W + 1.5W (Rated power)
Headphone Jack 3.5mm stereo phone jack
Microphone Jack No
USB Hub Not support
Tilt / Swivel Yes / No
7

Electrical Requirements
Standard Test Conditions
All tests shall be performed under the following conditions, unless otherwise specified.
Ambient light :Dark room
Viewing distance :40 cm for LCD performance, 20 cm for LCD failures
Warm up time
All specifications :＞30 minutes
Fully functional :5 seconds
Measuring equipment :Chroma 7120 signal generator or equivalent, directly
Connected to the monitor under test.
Minolta CA100 photometer, or equivalent
Control settings
User brightness control :Set to Factory preset value (cut off raster)
User contrast control : T Set to factory preset value, which allows that the brightest two
of 32 linear distributed gray-scales (0～700mv) can be
distinguished.
User red/white balance,
Green/white balance and
Blue/white balance control : In the center (unless otherwise specified)
Power input :230V±5％
Ambient temperature :20+5℃
Display mode :1680x1050, 60 Hz, all white
Measurement systems
The units of measure stated in this document are listed below:
1 gamma = 1 nano tesla
1 tesla = 10,000 gauss
cm = in x 2.54
Lb = kg x 2.2
Degrees F = [°C x 1.8] + 32
Degrees C = [°F - 32]/1.8
u' = 4x/(-2x + 12y + 3)
v' = 9y/(-2x + 12y + 3)
x = (27u'/4)/[(9u'/2) - 12v' + 9]
y = (3v')/[(9u'/2) - 12v' + 9]
nits = cd/(m2) = Ft-L x 3.426
lux = foot-candle x 10.76
8

LCD Monitor General Specification
9

10

LCD Panel Specification
LCD Panel Model (M220Z1-L01)
General Specifications
Mechanical Specification
11

Optical Specifications
Test Conditions
12

Supported Timing
VESA MODES
Horizontal Vertical
Mode Resolution Total
Nominal
Frequency
+/- 0.5kHz
Sync
Polarit
y
Nominal
Freq.
+/- 1 Hz
Sync
Polari
ty
Nominal
Pixel Clock
(MHz)
640x480@60Hz 800 x 525 31.469 N 59.940 N 25.175
640x480@72Hz 832 x 520 37.861 N 72.809 N 31.500
VGA
640x480@75Hz 840 x 500 37.500 N 75.00 N 31.500
800x600@56Hz 1024 x 625 35.156 N/P 56.250 N/P 36.000
800x600@60Hz 1056 x 628 37.879 P 60.317 P 40.000
800x600@72Hz 1040 x 666 48.077 P 72.188 P 50.000
SVGA
800x600@75Hz 1056x625 46.875 P 75.000 P 49.500
1024x768@60Hz 1344x806 48.363 N 60.004 N 65.000
1024x768@70Hz 1328x806 56.476 N 70.069 N 75.000
1024x768@72Hz 1304x798 57.7 P 72 P 78.4
XGA
1024x768@75Hz 1312x800 60.023 P 75.029 P 78.750
1280x1024@60Hz 1688x1066 63.981 P 60.020 P 108.000
1280x1024@70Hz 1688x1066 74.4 P 70 P 124.9
1280x1024@72Hz 1688x1066 77.9 P 72 P 134.6
1280x1024@75Hz 1688x1066 79.976 P 75.025 P 135.000
SXGA
1280x960@60Hz 1800x1000 60 P 60 P 108
1440x900@60Hz 1904x934 55.93 P 60 P 106.5
WSXGA 1680x1050@60Hz 2240x1089 65.29 N 59.95 P 146.25
IBM MODES
Horizontal Vertical
DOS 720x400@70Hz 900 x 449 31.469 N 70.087 P 28.322
DOS 640x350@70Hz 800 x 449 31.469 P 70.087 N 25.175
XGA 1024x768@72Hz 1304 x 798 57.515 P 72.1 P 75.000
MAC MODES
VGA 640x480@67Hz 864x525 35.000 N 66.667 N 30.240
SVGA
832x624@75Hz 1152x667 49.725 N 74.551 N 57.2832
1024x768@60Hz 1312x813 48.780 N 60.001 N 64.000XGA
1024x768@75Hz 1328x804 60.241 N 74.927 N 80.000
13

Monitor Block Diagram
The LCD MONITOR will contain a main board, a power board, and keypad board which house the flat panel control
logic, brightness control logic and DDC.
The Inverter board will drive the backlight of panel and the DC-DC conversion,
The Adapter will provides the 12V DC-power to inverter/power board.
Monitor Block Diagram
KEY BOARD
SPEAKER
IDPC LAMP
Analog in
LCD Controller
-Scaler
-OSD
-ADC
DC-DC
Flash room
PMC010
Adapter (12V)
Digital in
Audio IC
POWER(90V-264)
LCD PANEL
SPEAKER
14

Main Board Diagram
U402
PM25L010-25
RXD/TXD
KEY Control
AT24C16
U403
Panel
PA 0~9
PB 0~9
CAT24WC08
U407
U401
TSUMU58WHJ
HS/V
VAA3VCC1.8V
VCC3.3V
VAA1
VAA4
VAA2
DDC
CLK1/DAT1
AT24C02
(DDC)U301 DDCA SCL/SDA
VGA Input
VGA R/G/B
VGA Hsync/Vsync
AT24C02
(DDC)U302
DVI
Signal R/G/B
Clk+/Clk-
DDCD
SDA/SCL
MAIN BOARD DIAGRAM
15

Software Flow Chart
1
2
N
Y
5
Y
N
10
Y
N
12
Y
N
7
Y
N
6
4
8
9
14
11
13
Y
N
15
Y
N
16
17
19
N
18
Y
3
16

Remark:
1) MCU initializes.
2) Is the EEPROM blank?
3) Program the EEPROM by default values.
4) Get the PWM value of brightness from EEPROM.
5) Is the power key pressed?
6) Clear all global flags.
7) Are the AUTO and SELECT keys pressed?
8) Enter factory mode.
9) Save the power key status into EEPROM.
Turn on the LED and set it to green color.
Scalar initializes.
10) In standby mode?
11) Update the lifetime of back light.
12) Check the analog port, are there any signals coming?
13) Does the scalar send out an interrupt request?
14) Wake up the scalar.
15) Are there any signals coming from analog port?
16) Display "No connection Check Signal Cable" message. And go into standby mode after the
message disappears.
17) Program the scalar to be able to show the coming mode.
18) Process the OSD display.
19) Read the keyboard. Is the power key pressed?
17

Main Board Layout
Symbol Description Symbol Description
U401 IC TSUMU58WHJ-LF PQFP-128 U702 LM3485 MSOP-8 NS
X401 CRYSTAL 14.318MHzHC-49US CN302 DV1 CONNECTOR 24 PIN
U601 IC TDA7496T 1.2W*2 DIP-20 ST CN601 WAFER 4P RIGHT ANGLE
U403 M24C16-WMN6TP CN702 WAFER 6P RIGHT ANGLE PITCH 2.0
U402 IC PM25LV010-25 SCE SOIC-8 PMC CN402 WAFER 30P 2.0MM RIGHT ANGLE
U407 CAT24WC08W SOIC-8 CN602 PHONE JACK 5PIN
U601 IC TDA7496T 1.2W*2 DIP-20 ST CN603 PHONE JACK 5PIN
U301 M24C02-WMN6TP CN701 DC JACK 3PIN
18

Cha
p
ter 2
Adjusting the viewing angle
•For For optimal viewing it is recommended to look at the full face of the monitor, then adjust the monitor’s angle to
your own preference.
•Hold the stand so you do not topple the monitor when you change the monitor’s angle.
•You can adjust the angle of the monitor from -5° to 15°, but please notice that the rear obliquity of the monitor must
not be over 15° when you adjust it, otherwise the machine may be inclined.
NOTES
•Do not touch the LCD screen when you change the angle. It may cause damage or break the LCD screen.
•Careful attention is required not to catch your fingers or hands when you change the angle.
19

Rear Bezel
Item Description Item Description
1. D-SUB Cable 4. External Adapter
2. DC-Jack Power Cable 5. DVI Cable
3. AC Power Cord 6. Audio Cable
20