AOC 177sa User manual

17” LCD Color Monitor AOC 177Sa
1
JH
Service
Service
Service
Horizontal Frequency
30-80 kHz
TABLEOFCONTENTS
Description Page Description Page
N
SAFETY NOTICE
ANY PERSON ATTEMPTING TO SERVICE THIS CHASSIS MUST FAMILIARIZE HIMSELF WITH THE
CHASSIS AND BE AWARE OF THE NECESSARY SAFETY PRECAUTIONS TO BE USED WHEN SERVICING
ELECTRONIC EQUIPMENT CONTAINING HIGH VOLTAGES.
Table Of Contents.......……..............................…........1
Revision List.…........................................……......2
Important Safety Notice.…….........................……......3
1.Monitor Specification..............................………........4
2.LCD Monitor Description…………………………….......5
3.Operation Instruction……..………...............……...........6
3.1.General Instructions………..........................…...........6
3.2.Control Button…………….…..............……...............6
3.3.Adjusting the Picture...........................…............7
4.Input/Output Specification............……………............9
4.1.Input Signal Connector............………….................9
4.2 Power Supply Requirement…………………………10
4.3.Factory Preset Display Modes.........................10
4.4.Panel Specification.....……...……………..................11
5.Block Diagram………...................…………................14
5.1.Software Flow Chart………………………................14
5.2.Electrical Block Diagram…………………..….......16
6.Schematic…………………...................................…18
6.1.Main Board........................................................18
6.2. Audio Board.....………..…....................................23
6.3. Power Board....…..….….......................................24
7.PCB Layout..……………….......................................26
7.1.Main Board……..………........................................26
7.2.Audio Board…....................................................29
7.3.Power Board………...............................................30
7.4.Key Board…………...…….....................................32
8.Maintainability…………….........................................33
8.1.Equipments and Tools Requirement...............33
8.2.Trouble Shooting…………..............................34
9.White-Balance Luminance adjustment………….....40
10.Monitor Exploded View……………………….........42
11.BOM List….....................................................44
12.Different Parts List…….………………......…………65
CAUTION: USE A SEPARATE ISOLATION TRANSFOMER FOR THIS UNIT WHEN SERVICING

17” LCD Color Monitor AOC 177Sa
2
Revision List
Revision Date Revision History TPV Model
A00 Apr.-10-07 First Version Release T76CM5DBF1ACAP
Add New Model In Item 11 T78CM5DBF1ACANE
A01 Oct.-30-08
Add New Model In Item 12 T78CM5DCF1ACANE

17” LCD Color Monitor AOC 177Sa
3
Important Safety Notice
Proper service and repair is important to the safe, reliable operation of all AOC Company Equipment. The service
procedures recommended by AOC and described in this service manual are effective methods of performing service
operations. Some of these service operations require the use of tools specially designed for the purpose. The
special tools should be used when and as recommended.
It is important to note that this manual contains various CAUTIONS and NOTICES which should be carefully read in
order to minimize the risk of personal injury to service personnel. The possibility exists that improper service
methods may damage the equipment. It is also important to understand that these CAUTIONS and NOTICES ARE
NOT EXHAUSTIVE. AOC could not possibly know, evaluate and advise the service trade of all conceivable ways in
which service might be done or of the possible hazardous consequences of each way. Consequently, AOC has not
undertaken any such broad evaluation. Accordingly, a servicer who uses a service procedure or tool which is not
recommended by AOC must first satisfy himself thoroughly that neither his safety nor the safe operation of the
equipment will be jeopardized by the service method selected.
Hereafter throughout this manual, AOC Company will be referred to as AOC.
WARNING
Use of substitute replacement parts, which do not have the same, specified safety characteristics may create shock,
fire, or other hazards.
Under no circumstances should the original design be modified or altered without written permission from AOC.
AOC assumes no liability, express or implied, arising out of any unauthorized modification of design.
Servicer assumes all liability.
FOR PRODUCTS CONTAINING LASER:
DANGER-Invisible laser radiation when open AVOID DIRECT EXPOSURE TO BEAM.
CAUTION-Use of controls or adjustments or performance of procedures other than those specified herein may
result in hazardous radiation exposure.
CAUTION -The use of optical instruments with this product will increase eye hazard.
TO ENSURE THE CONTINUED RELIABILITY OF THIS PRODUCT, USE ONLY ORIGINAL MANUFACTURER'S
REPLACEMENT PARTS, WHICH ARE LISTED WITH THEIR PART NUMBERS IN THE PARTS LIST SECTION OF
THIS SERVICE MANUAL.
Take care during handling the LCD module with backlight unit.
-Must mount the module using mounting holes arranged in four corners.
-Do not press on the panel, edge of the frame strongly or electric shock as this will result in damage to the screen.
-Do not scratch or press on the panel with any sharp objects, such as pencil or pen as this may result in damage to
the panel.
-Protect the module from the ESD as it may damage the electronic circuit (C-MOS).
-Make certain that treatment person’s body is grounded through wristband.
-Do not leave the module in high temperature and in areas of high humidity for a long time.
-Avoid contact with water as it may a short circuit within the module.
-If the surface of panel becomes dirty, please wipe it off with a soft material. (Cleaning with a dirty or rough cloth may
damage the panel.)

17” LCD Color Monitor AOC 177Sa
4
1. Monitor Specifications
Items Descriptions
Driving system TFT Color LCD
Type CLAA 170EA
Size 43.2cm (17")
Pixel pitch 0.264mm( H )x 0.264mm( V )
Viewable angle 160˚(H) 160˚(V) (TYPE)
LCD Panel
Response time (type) 5 ms for CPT
R,G,B Analog Interface
Video
Digital Interface
Connector 15-pin D-Sub
Video Signal Analog:0.7Vp-p(standard),
75 OHM, Positive
Sync. Type H/V TTL
H-Frequency 30kHz – 80kHz
Input
V-Frequency 56-75Hz
ON Mode ≤37W
Power Consumption
OFF Mode ≤2W
Contrast Ratio 800:1
Dot Clock 135 MHz
White Luminance 300cd/m2
Max. Resolution 1280 x1024
Display Color 16.2M colors
Plug & Play VESA DDC2BTM
Power Source 100~240VAC,47~63Hz
Maximum Screen
Size
Horizontal : 337.92 mm
Vertical: 270.34 mm
Environmental
Considerations
Operating Temp: 5°C to 35°C
Storage Temp: -20°C to 60°C
Operating Humidity: 10% to 85%

17” LCD Color Monitor AOC 177Sa
5
2. LCD Monitor Description
The LCD MONITOR will contain a main board, an audio board, a power board and a key board which house the flat
panel control logic, brightness control logic and DDC.
The power board will provide AC to DC Inverter voltage to drive the backlight of panel and the main board chips
each voltage.
Monitor Block Diagram
AC-IN
100V-240V
Power Board
(
Include: ada
p
ter
,
inverter
)
Flat Panel and
CCFL backlight
RS232 Connector
For white balance
adjustment in factory
mode
CCFL Drive.
Video signal, DDC
Key Board
HOST Computer
Audio Board
Main Board

17” LCD Color Monitor AOC 177Sa
6
3. Operating Instructions
3.1 General Instructions
Press the power button to turn the monitor on or off. The control buttons are located at front panel of the monitor.
By changing these settings, the picture can be adjusted to your personal preferences.
-The power cord should be connected.
-Connect the video cable from the monitor to the video card.
-Press the power button to turn on the monitor, the power indicator will light up.
3.2 Control Buttons
Item Name Within OSD Without OSD
1 Power Button/Power
Indicator Power On / Off Power On / Off
2 > / Volume Control 1.Move the cursor up
2.Increase the value of the selected
Activate the audio menu
3 < /Volume Control 1.Move the cursor down
2.Decrease the value of the selected
Activate the audio menu
4 Menu/Enter Select Function or select Sub menu Activate OSD main menu
5 Auto/Exit Exit OSD or back to previous menu Auto configuration

17” LCD Color Monitor AOC 177Sa
7
3.3 Adjusting the Picture
OSD functions
Main Menu Item
Main
Menu
Icon
Sub Menu
Item
Sub
Menu
Icon
Description
Contrast
Contrast from Digital-register.
Luminance
Brightness
Backlight Adjustment
Focus
Adjust Picture Phase to reduce Horizontal-Line noise
Image Setup
Clock
Adjust picture Clock to reduce Vertical-Line noise.
H. Position
Adjust the horizontal position of the picture.
Image Position
V. Position
Adjust the vertical position of the picture.
Warm N/A Recall warm Color Temperature from EEPROM.
Cool N/A Recall cool Color Temperature from EEPROM.
sRGB N/A Recall sRGB Color Temperature from EEPROM.
User / Red
Red Gain from Digital-register.
User / Green
Green Gain Digital-register.
Color Temp.
User / Blue
Blue Gain from Digital-register.
Input Select Yes N/A
Auto Adjust the H/V Position, Focus and Clock of
picture.

17” LCD Color Monitor AOC 177Sa
8
No N/A Do not execute Auto Config, return to main menu.
H. Position
Adjust the horizontal position of the OSD.
V. Position
Adjust the vertical position of the OSD.
OSD Setup
OSD Timeout
Adjust the OSD timeout.
Language
Language N/A Select the language you like.
Information
Information N/A
Show the resolution, H/V frequency and input port of
current input timing.
Yes N/A
Clear each old status of Auto-configuration and set
the color temperature to Cool.
Reset
No N/A Do not execute reset, return to main menu.
Exit
N/A N/A Exit OSD

17” LCD Color Monitor AOC 177Sa
9
4. Input/Output Specification
4.1 Input Signal Connector
1. D-SUB connector
Pin No. Description Pin No. Description
1. Red 9. + 5V
2. Green 10. Detect Cable
3. Blue 11. Ground
4. Ground 12. DDC-Serial Data
5. DDC-Return 13. H-Sync
6. R-Ground 14. V-Sync
7. G-Ground 15. DDC-Serial Clock
8. B-Ground
VGA connector layout

17” LCD Color Monitor AOC 177Sa
10
4.2 Power Supply Requirement
A/C Line voltage range : 100 V ~ 240 V
A/C Line frequency range : 50 ±3Hz, 60 ±3Hz
Current : TBD
Peak surge current : < 55A peak at 240 VAC and cold starting
Leakage current : < 3.5mA
Power line surge : No advance effects (no loss of information or defect) with a
maximum of 1 half-wave missing per second
DC output Voltage : 12VDC ± 5％
Current (max) : 3.5 Amp (12V)
4.3. Factory Preset Display Modes
Standard Resolution Horizontal
Frequency
Vertical
Frequency
Dos-mode 720 × 400 31.47kHz 70.0Hz
640 × 480 31.47kHz 60.0Hz
VGA 640 × 480 37.50kHz 75.0Hz
800 × 600 37.879kHz 60.0Hz
SVGA 800 × 600 46.875kHz 75.0Hz
1024 × 768 48.363kHz 60.0Hz
1024 × 768 56.476kHz 70.0Hz
1024 × 768 60.021kHz 75.0Hz
1024 × 768 48.780 60.0Hz
XGA
1024 × 768 60.241 75.0Hz
1280 × 1024 64.000kHz 60.0Hz
SXGA
1280 × 1024 80.00 75.0Hz

17” LCD Color Monitor AOC 177Sa
11
4.4. Panel Specification
4.4.1 Features
- Super wide viewing angle
- Super high contrast ratio
- Super fast response time
- High color saturation (EBU Like Specifications)
- SXGA (1280 x 1024 pixels) resolution
- DE (Data Enable) only mode
- LVDS (Low Voltage Differential Signaling) interface
- PSWG compatible
- RoHS compliance
- TCO’03 compliance
4.4.2 Display Characteristics

17” LCD Color Monitor AOC 177Sa
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4.4.3 Optical Characteristics

17” LCD Color Monitor AOC 177Sa
13
4.4.4 Electrical Characteristics
1. TFT LCD Module
2. Backlight Unit

17” LCD Color Monitor AOC 177Sa
14
5. Block Diagram
5.1 Software Flow Chat
1
2
N
Y
5
Y
N
1
Y
N
12
Y
N
7
Y
N
6
4
3
8
9
14
11
13
Y
N
15
Y
N
16
17
19
Y
N
18

17” LCD Color Monitor AOC 177Sa
15
1) MCU initialize.
2) Is the EPROM blank?
3) Program the EPROM by default values.
4) Get the PWM value of brightness from EPROM.
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 EPROM.
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
disappear.
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” LCD Color Monitor AOC 177Sa
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5.2 Electrical Block Diagram
5.2.1 Main Board
EEPROM
M24C16
(U403)
Flash Memory
PM25LV512-25SCE
(U402)
Scalar IC TSUM16AK
(Include MCU, ADC, OSD)
(U401)
EEPROM
M24C02
(U404)
H sync
V sync
RGB
SCL_VGA,
SDA_VGA
LCD Interface
(CN101)
D-Sub
Connector
(CN405)
Crystal
14.318MHz
(X401)
Key Board
Control
(CN403)

17” LCD Color Monitor AOC 177Sa
17
5.2.2 Inverter/Power Board
DIM
DIM
EMI filter
Start Circuit: R911
PWM
Control IC
Transformer
AC input
12V
ON/OFF
Control
PWM
Control IC
Feedback
Circuit
Output
Circuit Transformer MOSFET
Over
Voltage
Lamp
ON/OFF
5V
Bridge
Rectifier
and Filter
Feedback
Circuit
Rectifier
diodes
CN902

17"LCDColorMonitor AOC 177Sa
18
6. Schematic
6.1 Main Board
VLCD_12V
PB[6..11]
PA[8..13]
VCC1.8
B4
4.SCALER
RIN
GIN
SOG
BIN
GNDR
GNDG
GNDB
HSYNC
VSYNC
Adj_BACKLIGHT
VCC 1.8
Vcc 3.3
VCTRL
PA[0..7]
PA[8.. 13]
R+
R-
G-
G+
B+
B-
CLK+
CLK-
DDCD_SDA
DDCD_SCL
DET_DVI
DDCA_SDA
DDCA_SCL
DET_VGA
on_BACKLIGHT
on_Panel
+5V
PA[14..19]
PB[0..5]
PB[6..11]
GPO[0..4]
ESP
OSP
on_PANEL_12V
PB[12..23]
+12V
DDC_WP
VCC3.3
LVDS OUTPUT
+12V
PA[14..19]
VLCD
GPO[0..4]
VCC1.8
VLCD_12V
B3
3.INPUT
RIN
GIN
BIN
VSYNC
GNDR
GNDG
GNDB
DET_VGA
HSYNC
SOG
B+
CLK-
DET_DVI
CLK+
R+
G+
R-
B-
G-
DDCA_SDA
DDCA_SCL
DDCD_SDA
DDCD_SCL
+5V
DDC_WP
+3V3
TSUM56AK SCHEMATIC
TSUM56AK
TOP
A
B
05Monday , May 09, 2005
Tit l e
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Dat e: Sheet of
VLCD
+5V
+5V
XGA/SXGA
+5V
VCC 3.3
PC5V PB[12..23]
PA[0..7]
B5
5.PANEL INTERFACE
VLCD
PA[0..7]
PA[8. . 13]
ESP
PA[14..19]
PB[0..5]
PB[6..11]
GPO[0. .4]
OSP
VLCD_12V
PB[12..23]
B2
2.POW ER
on_Panel
on_BACKLIGHT
Adj_BACKLIGHT
+3V3
VCC1.8
VLCD
+5V
VCTRLPC5V
VCC 5V
VCC 3.3
on_PANEL_12V
VLCD_12V
+12V
VCC5V
+12V
PB[0..5]

17"LCDColorMonitor AOC 177Sa
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TSUM56AK
R716
NC
R720 0 1/16W
R704
100 1/16W
R32
1UF
P.S: The 1N4148 Vf=0.7V~1V can't meet
LDO spec. The BAT42, Vf is OK but the
If=200mA(forward current) can not
meet current spec.
VLCD 5
For RSDS and Panel VCC=12V
C704
NC
Q701
PMBS3904
VLCD _12V 5
+3V3
+3V3
Adj_BACKLIGHT
4
+5V3,4 PC5V 3
PC5V
BL_ADJ(DC)
C32
C718
0.1uF
+5V
X
+5V
R715
NC
TO-263
+3V3
+
C707
100uF/ 25V
C715
0.1uF
GND
+5V
H1
TP
1 2 3
4
5
6 7 8
9
1 2 3
4
5
6 7 8
9
R725
4.7K 1/ 16W
+12V
Q705
AO3401L
1K
+3V3
R726 NC/4K7
C708
1uF
+
C710
100uF/25V
POWER
A
B
15Monday , May 09, 2005
Tit le
Size Document Number Rev
Date: Sheet of
+12V
R732
10 1/16W
R31
R705 4.7K 1/16W
+3V3
VCC1.8 4
X
+5V
CN 701
CONN
2
4
6
8
10
12
1
3
5
7
9
11
0
C714
0.1uF
+12V
+5V
VLCD
+5V
H3
TP
1 2 3
4
5
6 7 8
9
1 2 3
4
5
6 7 8
9
R722
NC
1uF
Q707
PMBS3904
on_BACKLIGHT 4
P W M
D702
1N4148
MMBT3904
VCTRL 4
4.7K
R729
NC/10K
+5V3,4
+5V
C51
C709
0.1uF
GND
4K7
+5V
C720
NC/0.1uF
U702
AIC 1084-33PM
3
1
2
4
VIN
ADJ
VOUT
VOUT
R721
0 1/16W
VCC 3. 3 4
R707
4.7K 1/ 16W
VLCD _12V
VCC 1. 8
R713
NC
+
C702
4.7uF/16V
R723 51K 1/16W
+
C717
10uF/16V
R714
10K 1/16W
GND VCC3.3 4
C713
0.1uF
+5V
GND
R730
0 1/16W
+5V
R710 NC
D C
Q703
PMBS3904
Recommond to used "Blue" parts circuit
for VCC1.8V if you want to suppoert DDC
function when system power off
0V ~ 3.3V
C716
0.1uF
R703
2K 1/16W
+5V
R706 NC
Q706
PMBS3904
1UF
VCC5V
C701
NC
+
C703
100uF/25V
4.7K
R717
10K 1/16W
N.C
R29
R708
10K 1/16W
+12V
R701
1K 1/16W
47
R728
NC/4K7
+
C705
1uF/ 16V
D704
SMAL140
on_Panel_12V4
X
D704(SSM12L) Vf=0.38V and If=1A.
So when system power on, the
system loading is about 400mA
(3.3V is about 200mA and 1.8V is
about 200mA), So D35 changed
from 1N4148(or BAT42) to
SSM12L(schottky diode).
C711
0.1uF
VCC 3. 3
BL_ADJ
R731
NC
R709
0 1/16W
R724 51K
+12V 4
+5V3,4
D701
1N4148
+12V
SOT-223
X
12/21 MODIFY
C706
0.1uF
on_Panel4
R719
NC /10K
R712 4.7K 1/16W
D703
BAT54C
3
1 2
+5V
+
C719
NC /10uF/16V
+
C712
100uF/25V
R727
10K 1/16W
BL_ADJ
R702
51 1/16W
H2
TP
1 2 3
4
5
6 7 8
9
1 2 3
4
5
6 7 8
9
0V ~ 5V
R33
BL_ON
GND GND
R711
10K 1/16W
U701
NC/LT1117-18
3 2
1
4
VI VO
GND
VO
Q4
Q702
CH T2907
C
B
E
+5V
R718
NC/10K
4.7K
R31
Q704
AO3401L
VCC 3. 3

17"LCDColorMonitor AOC 177Sa
20
FB410 0 1/16W
DCLK-
D407
BAV70
3
1 2
C445
0.1uF
D404
BAV99
3
1 2
+5V 2,4
DAT2+
R442 100 1/16W
D425
RLZ36B
1 2
R447 1K 1/ 16W
R436 56 1/16W
PC5V
C435 0.047uF
DAT2-
C433 0.047uF
U404
M24C02
1
2
3
45
6
7
8A0
A1
A2
GNDSDA
SCL
WP
VCC
DDCD_SCL4
DVI5V
D410
MLL5232B 5.6V
R457 10K 1/16W
D414
LL5232B 5.6V 5%
+5V
D419
BAV99
3
1 2
R435 56 1/16W
R468 10 1/16W
R+ 4
D421
BAV99
3
1 2
CN405
DB15
1
6
2
7
3
8
4
9
5
11
12
13
14
15
10
1716
C454
0.1uF
D408
MLL5232B 5.6V
DDC_WP 4
R473
NC
R456 100 1/16W
TSUM56AK
R465 10 1/16W
R469 10 1/16W
BLUE+
DDCA_SDA4
DAT0-
C436 0.047uF
GIN 4
HSYNC 4
VGA_CON
D415
LL5232B 5.6V 5%
R444
10K 1/16W
U405
M24C02
1
2
3
45
6
7
8A0
A1
A2
GNDSDA
SCL
WP
VCC
PC5V
SCL_D VI
C444
0.1uF
GREEN+
R462 10 1/16W
D405
BAV99
3
1 2
G+ 4
GREEN-
D417
BAV99
3
1 2
C441 0.1uF
R434 56 1/16W
R460
10K 1/16W
R472
NC
RIN 4
C447
0.1uF
R464 10 1/16W
R450
10K 1/16W
D406
MLL5232B 5.6V
GND B 4
ESD_5V
R471
10K 1/16W
DET_VGA 4
+5V
C450
0.1uF
+5V
D423
BAV99
3
1 2
CLK+ 4
+5V
R440
75 1/16W
C446
0.1uF
C453
0.1uF
DCLK+
VSI
GND R 4
D411
MLL5232B 5.6V
RED-
R441 100 1/16W
FB409 120 OHM
R458 100 1/16W
R446 1K 1/16W
INPUT
A
B
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Tit l e
Size Document Number Rev
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D409
MLL5232B 5.6V
DDCA_SCL4
CLK- 4
C438 0.047uF
G- 4
D403
BAV99
3
1 2
D413
BAV70
3
1 2
R448
2.2K 1/16W
ESD_5V
D426
LL5232B 5.6V 5%
C443
220pF
R445 100 1/16W
D424
BAV99
3
1 2
DVI5V
C452
0.1uF
DDC_WP 4
SCL_VGA
C439 0.1uF
C448
0.1uF
DET_DVI 4
SDA_DVI
BLUE-
FB412 0 1/16W
B+ 4
R438
75 1/16W
D412
MLL5232B 5.6V
FB411 0 1/16W
SOG 4
VCC5V
HSI
DAT1+
R443 100 1/16W
VSYNC 4
DAT0+
R454 100 1/16W
C434 0.047uF
D416
LL5232B 5.6V 5%
C449
0.1uF
R449
2.2K 1/16W
DDCD_SDA4
R463 10 1/16W
R459
10K 1/16W
DAT1-
R455 100 1/16W
D422
BAV99
3
1 2
C437 0.047uF
D420
BAV99
3
1 2
PC5V
R452
10K 1/16W
R439
75 1/16W
CN406
JACK DVI
1
2
3
4
5
6
7
8
25
28
9
10
11
12
13
14
15
16
26
29
17
18
19
20
21
22
23
24
27
DAT2-
DAT2+
2/4shield
DAT4-
DAT4+
DDC SCL
DDC SDA
VSYNC
R
HSYNC
DAT1-
DAT1+
1/3shield
DAT3-
DAT3+
+5V
SYNC GN D
HPD
G
RGB GND
DAT0-
DAT0+
0/5shield
DAT5-
DAT5+
clk shield
clk+
clk-
B
R461
10K 1/16W
R451
10K 1/16W
R467 10 1/16W
C440 0.1uF
DVI5V
R470
1K 1/16W
R453 100 1/16W
GND G 4
R- 4
RED+
C451
0.1uF
SDA_VGA
D418
BAV99
3
1 2
BIN 4
B- 4
HPD
C432 0.047uF
R437 470 1/16W
R466 10 1/16W
C442
33pF