This manual may not, in whole or in part, be copied, Photocopied, reproduced, translated, or converted to any
electronic or machine readable form without prior written permission of InnoLux Tech. Corp. Ltd.
CHAPTER 5- TEST AND ADJUSTMENT ........................................................................................................................................ 13
1.1 TEST EQUIPMENT OR TOOL................................................................................................................................................ 13
1.2 PRESET TEST PATTERN ....................................................................................................................................................... 13
1.3 AC INPUT............................................................................................................................................................................. 13
1.7 WARM UP ............................................................................................................................................................................ 14
2.1 VIDEO SIGNAL INPUT .......................................................................................................................................................... 14
3.1 OSDFUNCTION TEST ......................................................................................................................................................... 15
3.3 AUTO COLOR BALANCE...................................................................................................................................................... 15
3.5 POWER CONSUMPTION FUNCTION TEST............................................................................................................................ 15
3.8 GROUNDING TEST ............................................................................................................................................................... 16
3.9 BUMPING TEST .................................................................................................................................................................... 16
5.2 COLOR TEMPERATURE CHECK .......................................................................................................................................... 18
5.3 BRIGHTNESS OUT (VIDEO SIGNAL INPUT 700MV±2%).................................................................................................... 18
6.2 AUDIO CONTROL TEST......................................................................................................................................................... 19
ATTACHMENT 1- BILL OF MATERIAL......................................................................................................................................... 26
This monitor is manufactured and tested on a ground principle that a user’s safety comes first.
However, improper used or installation may cause damage to the monitor as well as to the user.
WARNINGS:
zThis monitor should be operated only at the correct power sources indicated on the label on the rear
of the monitor. If you’re unsure of the power supply in you residence, consult your local dealer or
Power Company.
zDo not try to repair the monitor by yourself, as it contains no user-serviceable parts. This monitor
should only be repaired by a qualified technician.
zDo not remove the monitor cabinet. There are high-voltage parts inside that may cause electric
shock to human bodies.
z Stop using the monitor if the cabinet is damaged. Have it checked by a service technician.
z Put your monitor only in a lean, cool, dry environment. If it gets wet, unplug the power cable
immediately and consult your closed dealer.
zAlways unplug the monitor before cleaning it. Clean the cabinet with a clean, dry cloth. Apply
non-ammonia based cleaner onto the cloth, not directly onto the class screen.
zDo not place heavy objects on the monitor or power cord.
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 voltage, 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.
3. SERVICE NOTES
z When replacing parts or circuit boards, clamp the lead wires around terminals before soldering.
z Keep wires away from high voltage, high temperature components and sharp edges.
z Keep wires in their original position so as to reduce interference.
z Adjustment of this product please refers to the user’ manual.
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Acer Service Manual
Chapter 2- SERVICE TOOLS & EQUIPMENT REQUIRED
1. SIGNAL GENERATOR
2. MULTIMETER
3. SCREW DRIVER
4. OSCILLOSCOPE
5. Soldering IRON
6. SOLDER
7. VGA Cable (15pins point to point)
8. DVI Cable(DVI-D 24+1 pin)
9. Color Analyzer
10. Myson412 ISP Board
11. EDID Board
12. EDID program file
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Acer Service Manual
Chapter 3- CIRCUIT THEORY
1. Monitor Block Diagram
The LCD Monitor contains an interface board, and inverter/power/Audio board, keypad board and flat
panel. In Inverter/power/Audio board, power section supplies +14V & +5V for Inverter/Audio and
Interface board used. The inverter section drives the backlight of panel and the DC-DC conversion. The
Audio section drives speaker (2 x1W).
Flat panel (LVDS interface) and CCFL
Inverter/Power/Audio BD
(Including AC/DC Power
Supply , Inverter and
Audio)
AC input
Range 100V~240V
2. Interface BOARD DIAGRAM
Interface Board
Interface Board (VGA input)
Keypad BD
Host computer
(VGA signal input and DDC)
Red
Green
Blue
A/D
&
Scaling
&
Vsync
OSD
Hsync
SCL
MCU
EEPROM
SDA
DDC
5
To
LCD
module
Acer Service Manual
3. Electronic Circuit Theory
3.1 Switching Mode Power Supply
3.1.1 AC Current Input Circuit
P801 is a connector for connecting AC Power. F801 is a fuse to protect all the circuit. AC input
voltage is from 90v to 264V. R820 and R821 joined between two inputting main circuit to prevent
man from shock. L801 is used to clear up low frequency wave. C801 and C806 are used to discharge
the waves that L801 produced. High frequency waves are damped by C801 and C806. D801 is a
rectifier which composed of 4 build-in diodes, it inverts AC to DC.
3.1.2 High Voltage to Low Voltage Control Circuit
C805 is used to smooth the wave from rectifier. IC802 is a highly integrated PWM controller
which build-in power MOSFET. When rectified DC high voltage is applied to the DRAIN pin during
start-up, the MOSFET is initially off, and the CONTROL pin capacitor is charged through a switched
high voltage current source connected internally between the DRAIN and CONTROL pins. When the
CONTROL pin voltage Vc reaches approximately 5.8V, the control circuitry is activated and the
soft-start begins. The soft-start circuit gradually increases the duty cycle of the MOSFET from zero to
the maximum value over approximately 10ms. If no external feedback/supply current is fed into the
CONTROL pin by the end of the soft-start, the high voltage current source is turned off and the
CONTROL pin will start discharging in response to the supply current drawn by the control circuitry.
Resistor R803, R807, R824 and R825 are for line over voltage shutdown(OV) and line
under-voltage detection(UV).
Resistors R801, R805, R822, R823 are for external current limit adjustment. And used to reduce
the current limit externally to a value close to the operating peak current of primary about 1.35A. The
mean is power will protected when the primary current over about 1.35A.
When PWM is turned off, the main current flow will be consumed through D804, and ZD802,
This will prevent MOSFET which built-in IC802 from being damaged under large current impulse and
voltage spike.
D806 and C815 to provide internal Auxiliary current to CONTROL pin during normal operation.
Otherwise, error amplifier and feedback current input the CONTROL pin for duty cycle control.
3.1.3 DC_5V and DC_14V Output Circuit
For DC 5V, D805 is used to rectify the inducted current. R806 and C811 are used to store energy
when current is reversed. The parts including C814, C814, C822, C821, B801 and L803 are used to
smooth the current waves.
For DC 14V, D803 is used to rectify the inducted current. R802 and C802 are used to store
energy when current is reversed. The parts including C808, C810 and L802 are used to smooth the
current waves.
3.1.4 Feedback and OVP Protect Circuit
Pin R of IC803 is supplied 2.5-v stable voltage. It connects to 5V and 14V output through R811,
R810 and R818. R811, R810 and R818 are output sampling resistor. When the sampling voltage more
than 2.5V or less than 2.5V, current of FB IC802 will change, this can change the voltage from T801.
For 5VDC output OVP, ZD803 is a Zener Diode, when 5 voltage up to 5.6V, the zener current
cause R819 voltage to ground is up to 0.7V, Q801 being triggered and OVP working. For 14VDC
output OVP, ZD804 is a Zener Diode, when 14 voltage up to 18V, the Zener current cause R819
voltage to groung is up to 0.7V, Q801 being triggered and OVP working. The current of potential is
used to make build-in diode light. Current of FB to IC802 will be changed, this can change the voltage
from T801.
Q802, R827, R828 and ZD801 make up of dummy loading circuit. For start-up sequence, during
5V output take place high loading first, this dummy loading circuit operated to insure 14V not be
increased.
3.2 I/F Board Circuit
3.2.1 RGB CAPTURE
- Signal RED,GREEN,BLUE input through CN103 #1,#2,#3, Stop DC via C112, C114 and C116,
and then enter into U105 (TSUM56AL) analog input terminal #18,#20,#23, and then
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Acer Service Manual
TSUM56AL deals with signal internally. TVS101, TVS102, TVS103 are ESD protector to
prevent U105 from ESD.
- Signal DDC_SCL (series clock) inputs via CN103#15, and then passes through ZD101 Zener for
ESD protection, goes into U105 #31.
- Signal DDC_SDA (series data) inputs via CN103#12, and then passes through ZD107 Zener for
ESD protection, goes into U105 #30.
- Signal TTL vertical sync. (Vsync) inputs via CN103 #14, and then clamped by ZD105 Zener,
passes through R129, and then goes into IC U105 (TSUM56AL) #28.
- Signal TTL horizontal sync. (Hsync) inputs via CN103 #13, and then clamped byZD106 Zener,
passes through FB101,R130, and then goes into IC U105 (TSUM56AL) #27.
- CN103#5 is defined as cable detect pin, this detector realize passes through R122 Pull hight, go
into U105#35.
- U103 power is supplied by PC via CN103#9, or supplied by Monitor self via D103.
- U103 is an EEPROM IC which is memory and EDID data saved in it.
3.2.2 Buttons Control
- Button “Power” on right side bezel connects to U105 (TSUM56AL) #88 through R161, via
CN105#4.
- Button “UP” “DOWN ““MENU” “AUTO” on right side bezel connects to U105 (TSUM56AL)
#91,#90,#89,#92 through R158,R159,R160,R157,via CN105 #7, #6, #5, #8.
- U108 is an EEPROM IC which memory OSD setting and save the value adjusted by user.
- LED Indicator on Front Bezel
a. When press button “power”, U105 (TSUM56AL) #42 sends out a low potential, via R188,
flow to CN105 #2 on keypad, LED Blue ON.
b. When in “Suspend” mode, U105 (TSUM56AL) #41 sends out a low potential, via R189, flows
to CN105 #1 on keypad, LED Amber ON.
3.2.3 Mstar CHIP U105 (TSUM56AL)
- U105 (TSUM56AL) #54. #55. #58~#65 output 8 bit even LVDS digital data to panel control
circuit through CN104.
- U105 (TSUM56AL) #67~#74. #77. #78 output 8 bit odd LVDS digital data to panel control
circuit through CN104.
- U105 (TSUM56AL) #86 outputs Brightness “PWM” signals to control CCFL brightness.
- U105 (TSUM56AL) #48 output PPWR ”H” potential to make Q103 conducted, and then make
Q101 conducted, +5V flow to CN104#1~#3 as Panel VDD .
- U105 (TSUM56AL) #85 output CCFL_ON/OFF ”H” potential to control Inverter on/off.
- TCLK by Crystal 14.318MHz input to U105 (TSUM56AL) #96,#97.
Please refer to TSUM56AL Pin Assignments table in page
3.2.4 Regulator Circuit
- +5V is from switching mode power supply for Panel used.
- +3.3V generates from +5V through C101 and C103 filtering and U101 which is output +3.3V
LDO for U103, U106,U108 and U105 used.
- +1.8V generates from +5V through C101 and C103 filtering and U102 which is output +1.8V
LDO, for U105 used.
3.2.5 Audio circuit
- Audio Signal R,L,GND input through P701,#2,#5,#1, Stop DC via C711, C712, and then enter
into U701 (TDA7496L) analog input terminal #4,#9.
- U701 (TDA7496L) #14,#17 output R,L audio data to Speaker through CN701.
- U105 (TSUM56AL) #94 output MUTE “H” potential to control U701on/off.
- U105 (TSUM56AL) #93 outputs Volume “PWM” signals to control U701 Volume.
4. Inverter circuit
4.1 Low voltage to high voltage circuit
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Acer Service Manual
14VDC provides the power for IC501; the control signals Brightness and ON/OFF come from I/F
board. ON/OFF signal connect to pin8 of IC501 and makes IC501 enable. Brightness signal connect to
pin7 of IC501 and regulates the panel brightness, R526, D515, R529, C505 make up a network of
delaying time circuit and R523, R524 make up a divided voltage network, C504 is used to dump noise.
The operation frequency is determined by the external Resistor R522 and capacitor C529 connected to
pin5 of IC501. BURST MODE dimming pulse frequency and duty is regulated by I/F board. C503 is
used for soft start and compensation, C502, C528 are used for dump noise.
The output drives, include NDR4, NDRV2, PDRV3, PDRV1 (pins1, 3, 15, 16 respectively) output
square pulses to drive MOSFET U501, U502, and each of U501, U502 is consist of a N channel
MOSFET and a P channel MOSFET. U501 and U502 work as full-bridge topology, it is high efficient,
zero voltage switching.
During start up, VSEN (pin9) senses the voltage at the transformer secondary. When VSEN reaches
3.0V, the output voltage is regulated. If no current is sensed approximately 1.5 seconds IC501 shunt off.
The current flowing through CCFL is sensed and regulated through sense resistor R509, R511. The
feedback voltage through R506, R507, C508 connected to Pin11 (ISEN), then compared with a
reference voltage (1.5V) via a current amplifier, resulting in PWM drive outputs to full-bridge switches.
4.2 Protection circuit
OverVoltage Protection: R501and R502 are connected in high voltage output connector, the
divided AC voltage is inverted DC voltage through D508, R505 and C507are used to rectify wave &
dump noise. Then the voltage signal reaches Pin9 VSEN of IC501, when the voltage changes, build-in
PWM of IC501 will adjust output voltage.
Open Lamp Protection: In normal operation, the resistors R510, R511, R512, R509 are sensed a
high level AC voltage, the AC signal OP1 invert DC voltage through D509, R515, C533, and the high
level DC voltage reaches the gate pin of Q502, similarly, the gate pin of Q503, Q504, Q505 has high
level DC voltage. So the gate pin of Q501 has a low level voltage, and the IC501 is normal operation.
Once one of signal OP1, OP2, OP3, and OP4 is low, the voltages of Q501 gate pin is high level, and
make the voltage of ISEN low level, the IC501 will be shunt down.