Dell ST2010 - 20" LCD Monitor User manual

Service Manual
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0
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Service Manual
LCD Monitor ST2010

1
Service Manual Versions and Revision
No. Version Release Date Revision
1 1.0 2009/02/11 Initial Release
Copyright
Copyright 2007 InnoLux Display. Corp. Ltd
All Rights Reserved
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 Foxconn Tech. Corp. Ltd.
Dell ST2010 Service Manual

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Table of Contents
CHAPTER 1- PRECAUTIONS & SAFETY NOTICES................................................................................................
......................
SAFETY PRECAUTIONS................................................................................................................................
................................
PRODUCT SAFETY NOTICE................................................................................................................................
.............................
SERVICE NOTES ................................................................................................................................
................................
CHAPTER 2- SERVICE TOOLS & EQUIPMENT REQUIRED................................................................
................................
CHAPTER 3- CIRCUIT THEORY................................................................................................................................
.......................
1.BLOCK DIAGRAM ................................................................................................................................
................................
2.ELECTRONIC CIRCUIT THEORY................................................................................................................................
...........................
3. FACTORYPRESETTIMING TABLE ................................................................................................
................................
4. POWER ON/OFF SEQUENCY ................................................................................................................................
.............................
5. D-SUB CONNECTOR PIN ASSIGNMENT................................................................................................
................................
6.AC OUTLET PIN ASSIGNMENT ................................................................................................................................
.........................
7. INNER CONNECTOR PIN ASSIGNMENT................................................................................................
................................
8. KEY PARTS PIN ASSIGNMENTS................................................................................................................................
.........................
CHAPTER 4- DISASSEMBLY & ASSEMBLY................................................................................................
................................
1. EXPLODED DIAGRAM................................................................................................................................
................................
2. ST2010 DISASSEMBLY BLOCK ................................................................................................................................
......................
3. ST2010ASSEMBLY BLOCK................................................................................................................................
............................
CHAPTER 5- TESTAND ADJUSTMENT................................................................................................
................................
5.1 FUNCTION KEY DEFINITIONS................................................................................................................................
..........................
5.2 OSD CONTROL................................................................................................................................
................................
5.3 OSD MESSAGE ................................................................................................................................
................................
5.4 BURN-IN PATTERN................................................................................................................................
................................
5.5AUTO COLOR BALANCE (AUTOMATICALLY CALIBRATE CHIPADC PARAMETER BY USING CHIP
INTERNAL DAC.)................................................................................................................................................................
.................
5.6 UPGRADE FIRMWARE TO SERIAL VIA FLASH CABLE BY ISP_TOOLV4.100.EXE ................................
................................
CHAPTER 6- TROUBLE SHOOTING................................................................................................
................................
1. COMMON ACKNOWLEDGE ................................................................................................................................
...............................
2. NO POWER SUPPLY ................................................................................................................................
................................
3. POWER (INCLUDE IF +5VAND +3.3V) SUPPLY NORMAL BUT LED OFF AND NO DISPLAY ................................
................................
4. POWER (INCLUDE IF +5VAND +3.3V) SUPPLYAND DISPLAY NORMAL ONLY LED OFF................................
................................
5. POWER (INCLUDE IF +5VAND +3.3V) SUPPLY NORMAL BUT LEDAMBER ................................................................
.......................
6. POWER (INCLUDE IF +5VAND +3.3V) SUPPLY NORMAL ,KEY FUNCTION OK,BUT BACKLIGHT CAN’T
BE TURNED ON................................................................................................................................................................
.....................
7. BACKLIGHT ON,KEY FUNCTION AND LEDACCURATE INDICATION OK BUT NO PICTURE................................
................................
8. AT 32-GRAY SCALE PATTERN,COLOR LOST IN SOME SCALE................................................................
................................
CHAPTER 7- RECOMMENDED PART LIST................................................................................................
................................
ATTACHMENT 1- BILL OF MATERIAL ................................................................................................
................................
ATTACHMENT 2- SCHEMATIC................................................................................................................................
.......................
ATTACHMENT 3- PCB LAYOUT................................................................................................................................
......................

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Chapter 1- PRECAUTIONS & SAFETY NOTICES
SAFETY PRECAUTIONS
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:
lThis monitor should be operated only at the correct power sources
indicated on the rating label on the rear cover of the monitor. If you’re
unsure the power supply in your residence, consult your local dealer or
Power Company.
lUse only the specified power cord that comes with this monitor.
lDo 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.
lDo not remove the monitor cabinet. There is high-voltage parts inside
that may cause electric shock to human bodies.
lStop using the monitor if the cabinet is damaged. Have it checked by a
service technician.
lPut your monitor only in a lean, cool, dry environment. If it gets wet,
unplug the power cable immediately and consult your closed dealer.
lAlways 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.
lDo not place heavy objects on the monitor or power cord.
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.
SERVICE NOTES
lWhen replacing parts on circuit boards, clamp the solder wires around
terminals before soldering.
lKeep wires away from high voltage, high temperature components and
sharp edges.
lKeep wires in their original position so as to reduce interference.
lAdjustment of this product please refers to the user’ manual.
lUse Pb free solder wire for circuit board preparation.

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Chapter 2- SERVICE TOOLS & EQUIPMENT REQUIRED
1. SIGNAL GENERATOR
2. MULTIMETER
3. SCREW DRIVER
4. OSCILLOSCOPE
5. Soldering IRON
6. SOLDER (Lead free, RoHS compliance)
7. Color Analyzer
8. Fox_VISP_Programmer
9. Fox_VEDID_Programmer

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Chapter 3- CIRCUIT THEORY
1.Block Diagram
Dell ST2010 consists of a main body and a stand (base). The main body contains a
LCD module with 2 CCFL lamps, There are 4pcs PCBA in this monitor, one is
power& inverter which is a single layer board, one is interface board, one is
function keypad which is OSD control located on the right side back cover,one is
power DC_on/off key. The block diagram is shown as below(fig.1).
Lamp2
Photocoupler
Transformer
Snubber
&Schottky
Feedback
Control
Snubber
&Schottky
1
To Panel CCFL
MOSFET
Rectifier&
Filter
Circuit
Brightness/ ON/OF
Control
Power
MOSFET
AC Input
90V~264V
PWM Control
IC LD7575
Feedback
and OVP
+13V DC output
Power
Transformer
Lamp1
AC Line Filter
INL816
Fuse 5A/125V
+5V DC output +5V DC output

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Scalar
LVDS Data
Flash
Connector to power board
HDMI signal
3.3V
power saving control
Panel Vcc control
Panel Interface
TSUMU58EDJ-LF
5V 5V
1.8V
dynamic contrast ratio
3.3V
14.318MHz
Brightness /ON_OFF Control
AP1117E33A
VGAConnector
VGA signal
LM1117M-1.8
XTAL
OSD/KEY
24C16
EDID
24C02
HDMI Connector
Panel Vcc
on/off switch
Connector
LM1117M-3.3
Keypad
AP1117E18
EDID
24C02
Fig.1

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2.Electronic Circuit Theory
2.1 Inverter PWM circuit
2.1.1 Inverter Control circuit operations:(fig.2)
GND
DRV2
R11
100K D1 BAV70
R8
33K
ISEN
PWM
+5V
CN5
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
PIN1
PIN2
PIN3
PIN4
PIN5
PIN6
PIN7
PIN8
PIN9
PIN10
PIN11
PIN12
PIN13
PIN14
PIN15
C7
2.7n
U1
INL816
1
2
3
4
5
6
12
13
14
15
16
7
8 9
10
11
DRV1
VDDA
SEL
RT1
RT
PWM
OLP1
OLP2
SSTCMP
GND
DRV2
PID
TIMER ISEN1
ISEN2
VSEN
C2
10n
R10
20R
DRV1
+13V
R12
100K
DRV1
R3
10K
R7
33KC3
2.2u
VS1
C6
OPEN
C8
2.7n
R6
NC
R1 10R
R13
10K
R9
20R
Q1
AP9971
1
2
3
45 6
7
8
.
.
.
.. .
.
.
DIM/ON/OFF
C9
3.3n
VS1
R4 560K
Confidential
O2Micro Inc. All rights reserved
PID
C5
47n
C10
3.3n
R5
191K
+5V
OP
+13V
R2 10K
C1
1u
VS2
Fig.2
DC_5V through R1 and C1 will provide power for U1 on the
pin2.PWM-ON/OFFandDIM voltage signal coming from scalar which is on IF BD
will PWM U1 to work. During start up, ISEN (pin9and pin10) senses the voltage on
the transformer secondary. If no current is sensed approximately 2 seconds, U1 shuts
off. R3 is used to limit current. C3 is used to dump noise, C5 is used to soft start, and
then the voltage on pin 14 will enable U1.Once the voltage at the ISEN pin reaches
the lamp on threshold, the IC switches from the striking mode to the normal operation
mode and the PWM dimming control is activated.
The striking and operating frequency is determined by the external resistor
(R4andR5) and connected to Pin 4and Pin5.
DRV1 and DRV2 of U1 are used to drive U2 . DRV1 and DRV2 are controlled
by build-in PWM IC. Q1 is switched which has two build-in IGBTs. The working
principle of circuit of T1, the same to circuit of Power.
The voltage signal on negative pole of D1 sensed through R7/R8 comes to
Pin11 of U1 VSEN (Lamp Current Detection & Control). The CCFL current is
detected through R12/R21 and reaches a regulated value. The CCFL current detected
at resistor R12/R21 is converted to a voltage level and input to the ISEN. Once the
CCFLs are ignited and current is sensed through resistor R12/R21, performs the loop
compensation function. The voltage at IC pin12 controls the drive duty cycle of the

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power MOSFETs to regulate the CCFL current.
2.1.2 Output Circuit and Protection Circuit operations:(fig.3)
1
2
+
C25
680u/25V
OP
C22
12pF/3KV
ISEN
DRV2
DRV2
VS2
ISEN
PID
CN5
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
PIN1
PIN2
PIN3
PIN4
PIN5
PIN6
PIN7
PIN8
PIN9
PIN10
PIN11
PIN12
PIN13
PIN14
PIN15
VS2
DRV1
VS1
1
2
R21
133
+13V
C21
3pF/3KV
DRV1
OP
DIM/ON/OFF
T1
DIPEEL19 SPW-054
1
6
4
3
8
7
VS1
+5V
C20
3pF/3KV R20
133
+13V
Fig.3
The transformer (T1) secondary winding leakage inductance and output
capacitance(C31) forms a lower pass filter,which converts the square-wave driving
signal into a sinusoidal output voltage signal for CCFL.
The over-voltage protection feature is implemented by using an extermal
capacitor devider(C20/C21) to sense the output voltage.The divide-down voltage
signal is sent to the IC Pin11(VSEN) ,thus regulating the output voltage.
If a CCFL is removed, fails or damaged during normal operation, CCFL current
is no longer sensed and the voltage on ISEN pin drops. Once the voltage at the ISEN
pin is less than the lamp” on” threshold, the shutdown timer is activated. The IC
maintains the output voltage for approximately 2-3seconds and once the timer expires,
the IC will shutdown. To restart the IC, either toggle the SST_CMP pin or recycle the
power on the VDDA pin.
2.2 Power PWM circuit operations
2.2.1) Block diagram:(fig.4)
EMI Filter Rectifier and
filter Isolation power transformer Rectifier and filter Inverter circuit
Rectifier and filter AUDIO

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R851 750K
C851
222 Y2
C850
222 Y2
L850
NC/CHK-106
4 3
1 2
C852
0.47uF X2
CN850
TU-301-AS
1 3
2
F850 3.15A 250V
R850 750K
VZ850 TVS
L850-1
CHK-090
4 3 1 2
AC INPUT(90V~265V) RT850
8R5A
Fig.4
2.2.2) AC Input and EMI Filter:(fig.5)
Fig.5
CN850 is a connector for connecting AC Power. F850 is a fuse to protect all the
circuit AC. Input voltage is from 90V to 264V. R850 and R851 are joined between
two inputting main circuit to prevent man from shock. L850 is used to filter low
frequency noise. C850 and C851 are used to discharge the noise that L851 produced.
High frequency waves are damped by C852 .
2.2.3)High Voltage to Low Voltage Control Circuit:(fig.6)

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D852
SF10-04
Signal_GND
Signal_GND
R855
10K
D853
TVS-P6KE170A
R853
0.2R
C872
NC/100P/1KV
-+
D850
BL4-06
3
1
2
4
Q850
AP2764
2
13
R856
10 1%
R869
0R68 2W
C875
4700p/250V
D851
FR10-10-LF
R880
82K2W
+
C855
10u/50V
CN852
CON8PIN
1
2
3
4
5
6
7
8
Gate
Isense
GND
FB
GND
VDD
NC
Vin
ZD881
OPEN
Signal_GND
+
C854
100u/450V

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C849
1nF/50V NPO
Signal_GND
U850
LD7575
1
45
2
83
7
6
RT
GNDOUT
COMP
HVIsense
NC
Vcc
Signal_GND
C848
100nF/50VX
R849
220R
R842
20K
Signal_GND
C846
220pF/50V NPO D849
NC
R841
10K/NC
CN852
CON8PIN
1
8
3
4
5
6
7
2
Gate
HV
GND
FB
GND
VDD
NC
Isense
Signal_GND
R846
100K/ 1%
Signal_GND
Signal_GND
R843
20K
R847
NC
R848 20R
C847
Open
Fig.6
D850 is a rectifier in which there are 4 build-in diodes, inverting AC to DC.
C854 is used to smooth the wave from rectifier. R852 is a fuse resistor to protect
the following circuit when inrush current is too large.
U850 is a current-mode PWM controller with excellent power-saving opration,It
features a high-voltage current source to directly supply the startup current from
bulk capacitor and further to provide lossless startup circuit. Max start-up current
for U850 is 100 uA, When current flow from the bulk capacitor C854 through R843
and R842 gets to HV pin to start up U850, Meanwhile,the VCC supply current is as
low as 100 uA thus most of the HV current is utilized to change the VCC capacitor
C855, Whenever the Vcc voltage is higher than UVLO (16V),the GATE pin will
output signal to drive the power MOSFET(Q850), the high-voltage current source is
off and the supply current is provided from the auxiliary winding of the trasformer
PIN5.
When U850 begins to operate Pin8 of U850 will output square wave to drive
Q850, then the main current flow get to GND bypassing through T850, Q850.
Because of the change of current flow, wires in the other side of T850 will induct
current. In the same time, the current inducted by wires which connected T850 Pin 1
and Pin 3, with components of D852, R856 and C855 ,will be supplied to U850 for

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normal operating.
The typical current mode PWM controller feedbacks both current signal and
voltage signal to close the control loop and achieve ragulation.U850 detects the
Q850 current from Isense pin which max voltage is set as 0.85V, then the Q850
current can be calculated as:I peak=0.85V/R869,When the sense voltage across the
sense resistor R869, reaches the threshold voltage over 0.85V, the output GATE
drive will be turned off. R849 and C846 is used to avoid the Isen pin damaged by
the negative turn-on spike.
The voltage feedback signal is provided from the TL431(I851) through the I850
to the COMP pin.When the voltage on COMP pin is lower than 1.2V,the IC will
turn off.
When Q850 is turned off, the main current flow will be consumed through
D851, C875, R880, this will prevent Q850 from being damaged under large
current impulse and voltage spike.
RT pin is to program the switching frequency ,by connecting R846 to
ground to set the switching frequency,f =(65.0/R846)*100(KHz).
2.2.4) DC 13V and DC 5V Output Circuit and Feedback circuit:(fig.7)
I850
LTV817
3
14
2
+13V
C860
3300p/250V
L851
CHK-053
R861
3K6 1%
C871
0.1/50V
+
C863
470u/25V
D854
NC/SF5-20
+
C867
470u/25V
C862
1000p/1000V
R860
3K3 1%
L852
CHK-053
I851
TL431
3
1
2
+
C869
470u/25V
R866
10R2W/JUMP
D856 SR5-10 F851
5A/125V
.
.
.
T851
NC
5
8
6
7
3
1
12
11
9
10
D855
SF5-20
C866
1000p/1000V
C876
0.1/50V
R859
10K 1%
+
C899
OPEN
D857 SR5-10
.
.
.
T850
SPW-119
5
8
6
7
3
1
12
11
9
10
R867
270
C861 OPEN
R862
10R2W/JUMP
DIM/ON/OFF
+5V
PID
+
C868
470u/25V
CN851
SIP-8P
6
1
2
5
3
4
7
8
+5V
+5V
GND
GND
DIM
ENA
PID
P-saving_on/off
R858
5K1 1%
+
C864
470u/25V
R871
270k
R899 OPEN
C859
0.01/50V
Fig.7
D855 is used to rectify the inducted current. R862 and C862 are used to store

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energy when current is reversed. The parts including C862, C863 C864 andL852
are used to smooth the current waves that are from D855, then 13V voltage is
supplied.
D856 is a SCHTKY diode used to rectify the inducted current.C866 and R866
are used to store energy when current is reversed,The components including
C867,C868andL851, C867 and C868 are used to smooth the current waves,then
DC+5V voltage is supplied. F851 is used for OCP for the LPS test.
DC 5V supply voltage feed back to PWM controller U850 via,
R861,R860,R859,C859,I851,R867
Used to control the voltage feedback loop.
2.3 I/F Board Circuit (see the Attachment 2- Schematic)
2.3.1 RGB CAPTURE
- Signal RED,GREEN,BLUE input through CN102 #1,#2,#3, Stop DC via C113,
C114 and C115, and then enter into U105 (TSUM58EDJ-LF) analog input
PIN #28,#25,#23, and then TSUM58EDJ-LF deals with signal internally.
D103, D104, D105 are ESD protector to prevent U105 from ESD.
- Signal DDC_SCL (series clock) inputs via CN102#15, and then passes through
ZD106 for ESD protection, goes into EDID EEPROM IC U103 #6.
- Signal DDC_SDA (series data) inputs via CN102#12, and then passes through
ZD103 for ESD protection, goes into EDID EEPROM IC U103 #5.
- Signal TTL vertical sync. (Vsync) inputs via CN102 #14, and then clamped by
ZD105 Zener, passes through R116, and then goes into IC U105
(TSUM58EDJ-LF) #33.
- Signal TTL horizontal sync. (Hsync) inputs via CN101 #13, and then clamped
by ZD104 Zener, passes through R115, and then goes into IC U105
(TSUM58EDJ-LF) #32.
- CN102#5 is defined as cable detect pin ,the detect pin can create a pull-low
signal send to U105#36pin via R160 to identity cable connection, if plug out
the VGA cable the U105#36pin will receive a high signal and system enter self
test mode when exit factory mode（the device must set at VGA input mode ）.
- U103 is an EEPROM IC which is memory and EDID data saved in it,the IC
power is supplied by PC via CN102#9 with D106 and ZD102 for ESD protection,
or supplied by Monitor self via D106.
2.3.2 HDMI CAPTURE
- TMDS differential Signal input
RX0+,RX0-,RX1+,RX1-,RX2+,RX2-,RXC+,RXC- through CN201
#7,#9,#4,#6,#1,#3,#10,#12 via R206,R205,R204,R203,R202,R201,R208,R207
enter into U105 (TSUM58EDJ-LF) Digital input terminal
#15,#16,#12,#13,#9,#10,#18,#19, and then TSUM58EDJ-LF-LF deals with
signal internally.
- Signal DDC_SCL (series clock) inputs via CN201#15, via R209, goes into
EDID EEPROM IC U201 #6.
- Signal DDC_SDA (series data) inputs via CN201#16, via R210, goes into
EDID EEPROM IC U201 #5.
- CN201#17 is defined as cable detect pin, the detect pin can create a pull-low
signal send to U105#3pin via R158 to identity cable connection, if plug out the

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HDMI cable the U105#3pin will receive a high signal and system enter self test
mode when exit factory mode（the device must set at HDMI input mode ）.
- U204 is an EEPROM IC which is memory and HDMI input EDID data saved
in it ,the U204 power is supplied by PC via CN201#18 through D201, or
supplied by Monitor self via D201.
2.3.3 Buttons Control
- Button “Power” on right corner of front bezel connects to U105
(TSUM58EDJ-LF ) #119 through CN104 #1 and R153, U105 #119 is defined
as power on/off.
- Button “+” and “-” on right corner of front bezel connects to U105
(TSUM58EDJ-LF) #120 through CN104 #2and R154, U105#120 is defined as
“Plus and minus” using with AD converting control technology.
- Button “Menu” and “Exit”on right corner of front bezel connects to U105
(TSUM58EDJ-LF) #121 through CN104 #4and R155, U105 #121 is defined
as “Menu”and “Exit” using with AD converting control technology.
- LED Indicator on Front Bezel
a.When press button “power”, U105 (TSUM58EDJ-LF) #123 be send in low
Voltage, make Q107#3 sends out high Voltage to CN104#3 , and then to
keypad, LED blue on.
b. When in “Suspend” mode, U105 (TSUM58EDJ-LF) #124 sends out a low
Voltage, make Q108#3 sends out high Voltage to CN104#5 , and then to
keypad, LED Amber on.
2.3.4 MAIN CHIP U105 (TSUM58EDJ-LF)
- U105 (TSUM58EDJ-LF ) #86~#77 output 8 bit even and #100~#91 output 8
bit odd LVDS digital data to panel control circuit through CN103.
- U105 (TSUM58EDJ-LF ) #73 output PPWR ”H” potential to make Q104
conducted, and then make Q101 conducted, +5V flow to CN103#1~#3 as
Panel Vdd .
- U105 (TSUM58EDJ-LF) #125 outputs Brightness “PWM” signals to control
CCFL brightness and on/off.
- TCLK by Crystal 14.318MHz input to U105 (TSUM58EDJ-LF) #128.
- U105(TSUM58EDJ-LF) #108 is RESET signals input pin
Please refer to TSUM58EDJ-LF Pin Assignments table in page
2.3.5 Regulator Circuit
- +5V is from switching power supply .
- +3.3V is generated from Regulator U101 which is supplied by+5V through
C101 filtering, C102 and C105 is 3.3V which supplies toU102、U106、U103、
U201、U105、U108output filtering.
- +1.8V is generated from Regulator U102 which is supplied byU101-3.3V
through C106 filtering.TheU102 output1.8V via FB105 send to U105.
3. FACTORY PRESET TIMING TABLE
3.1 VGA

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Resolution Pixel clock
H-sync
V-sy
nc
(unit:MHz)
(unit:KHz)
(unit
:Hz)
640x480 25.17 31.47 59.94
640x480 31.50 37.50 75.00
720x400 28.32 31.47 70.08
800x600 40.00 37.88 60.32
800x600 49.50 46.88 75.00
1024x768 65.00 48.36 60.00
1024x768 78.75 60.02 75.03
1152x864 108.00 67.50 75.00
1280x800 83.50 49.702 59.81
1280x1024 108.00 63.98 60.02
1280x1024 135.00 79.976 75.02
5
1600x900R
97.750 55.54 59.97
8
3.2 HDMI
Resolution Pixel clock
H-sync V-sync
(unit:MHz) (unit:KHz) (unit:Hz)
640x480 25.17 31.47 59.94
640x480 31.50 37.50 75.00
720x400 28.32 31.47 70.08
800x600 40.00 37.88 60.32
800x600 49.50 46.88 75.00
1024x768 65.00 48.36 60.00
1024x768 78.75 60.02 75.03
1152x864 108.00 67.50 75.00
1280x800 83.50 49.702 59.81
1280x1024 108.00 63.98 60.02
1280x1024 135.00 79.976 75.025
1600x900R 97.750 55.54 59.978
4. Power On/Off Sequency
Hardware power On/Off
When power-cord plug into AC socket, power board will provide DC_5V to
interface board.
DC_5V is main voltage for panel and Regulator U101.
DC_3.3V is coming from Regulator U101, DC_3.3v is main voltage for U105.
When DC_3.3V input to U105 and U105 reset circuit active, U105 all registers
will be set to default, that means finish hardware power on.
When pull out power cord fromAC socket,the system shut down instantly for no
supply

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Software power On/Off
- When press power key, U105 #119 receives low pulse, then
U105(TSUM58EDJ-LF) will be wake up and send control signals(at
U105#125pin and #73Pin) to on CCFL and switch 5.0v to panel module, at the
same time,U105 make the VGA/HDMI cable input signal source display normal
on panel if the VGA/HDMI cable input signal is active
-If power ON, U105 #123 (LED_blue) will send out low potential, and then LED
blue on.
-If power saveing, U105 #124 (LED_Amber) will send out low potential, and
then LED Amber on.
-If power ON or power saveing, when press power key, U105 #119 pin receives
low pulse, then U105 will be sleeping and turn off backlight, at the same time,
the panel will lose +5V.
The Panel_Vcc, Backlight_En, CLK/DATA output to panel will follow the following
sequency.

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Power supply for panel+5V VDD
90% 90%
10%
0V 10%
T1 T2
T5 T6 T7
Signals Valid data
(Digital RGB, HS, VS, DE, CLOCK)
0V
T3 T4
Power supply for backlight
T1(ms) T2 (ms) T3 (ms) T4 (ms) T5 (ms) T6 (ms) T7(ms)
SPEC(Samsun
g)
0.3~10 0.0~50 >500 >100 0.0~50 NA >1000
5. D-SUB Connector Pin Assignment
6. AC Outlet Pin Assignment
Pin Symbol Description
1 Line
2 GND
3 Neutral
7. Inner Connector Pin Assignment
7.1 CN103 (Connect interface board to Panel,)
Pin Symbol Pin Symbol Pin Symbol
1 Red 6 Red_GND 11 GND
2 Green 7 Green_GND 12 DDC_SDA
3 Blue 8 Blue_GND 13 Hsync
4 GND 9 PC+5V 14 Vsync
5 Cable Detect 10 GND 15 DDC_SCL
CN850
1 3
2

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Pin Symbol Description
1 Panel_Vcc Panel power supply (typ.5.0V)
2 Panel_Vcc Panel power supply (typ. 5.0V)
3 Panel_Vcc Panel power supply (typ. 5.0V)
4 NC
5 NC
6 NC
7 GND_LVDS LVDS Ground
8 RXE3+ LVDS signal of even channel 3(-)
9 RXE3- LVDS signal of even channel 3(+)
10 RXEC+ LVDS signal of even channel clock (+)
11 RXEC- LVDS signal of even channel clock (-)
12 RXE2+ LVDS signal of even channel 2(+)
13 RXE2- LVDS signal of even channel 2(-)
14 GND_LVDS LVDS Ground
15 RXE1+ LVDS signal of even channel 1(+)
16 RXE1- LVDS signal of even channel 1(-)
17 GND_LVDS LVDS Ground
18 RXE0+ LVDS signal of odd channel 0(+)
19 RXE0- LVDS signal of odd channel 0(-)
20 RXO3+ LVDS signal of odd channel 3(+)
21 RXO3- LVDS signal of odd channel 3(-)
22 RXOC+ LVDS signal of even channel clock (+)
23 RXOC- LVDS signal of even channel clock (-)
24 GND_LVDS LVDS Ground
25 RXO2+ LVDS signal of even channel 2(+)
26 RXO2- LVDS signal of even channel 2(-)
27 RXO1+ LVDS signal of even channel 1(+)
28 RXO1- LVDS signal of even channel 1(-)
29 RXO0+ LVDS signal of odd channel 0(+)
30 RXO0- LVDS signal of odd channel 0(-)
7.2 CN1, CN2 (Connect to Panel Backlight,)
Pin Symbol Description
1 HV High voltage for lamp
2 LV Low voltage for lamp
7.3 CN104 (Connect to keypad, WAFER2*4P or compatible connector)
Pin Symbol Description
1 POWER OSD “POWER” control
2 MINUS/PLUS OSD “PLUS” or “MINUS” control
3 LED_white LED white on/off control
4 MENU/ENTER OSD “MENU/ENTER ” control
5 LED_Amber LED Amber on/off control
6 GND Ground
7 GND Ground
8 GND Ground

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