Dell E2009W User manual

Service Manual
- 0 -
Service Manual
LCD Monitor E2009W

1
Service Manual Versions and Revision
No. Version Release Date Revision
1 1.0 2008-9-1 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 E2009 Service Manual

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Table of Contents
CHAPTER 1- PRECAUTIONS & SAFETY NOTICES..................................................................................................................... 3
1. SAFETYPRECAUTIONS .................................................................................................................................................... 3
2. PRODUCTSAFETYNOTICE.............................................................................................................................................. 3
3. SERVICE NOTES.................................................................................................................................................................. 3
CHAPTER 2- SERVICE TOOLS & EQUIPMENT REQUIRED ..................................................................................................... 4
CHAPTER 3- CIRCUIT THEORY ...................................................................................................................................................... 5
1. BLOCK DIAGRAM ................................................................................................................................................................... 5
2. ELECTRONIC CIRCUIT THEORY ............................................................................................................................................... 7
3. FACTORY PRESETTIMING TABLE................................................................................................................................ 13
4. POWER ON/OFF SEQUENCY .................................................................................................................................................. 13
5. D-SUB CONNECTOR PIN ASSIGNMENT................................................................................................................................. 14
6. AC OUTLET PIN ASSIGNMENT .............................................................................................................................................. 14
7. INNER CONNECTOR PIN ASSIGNMENT................................................................................................................................... 14
8. KEY PARTS PIN ASSIGNMENTS.............................................................................................................................................. 16
CHAPTER 4- DISASSEMBLY &ASSEMBLY................................................................................................................................. 21
1. EXPLODED DIAGRAM ........................................................................................................................................................... 21
2. E2009W DISASSEMBLY BLOCK ............................................................................................................................................ 22
3. ASSEMBLY BLOCK................................................................................................................................................................ 23
CHAPTER 5- TESTAND ADJUSTMENT........................................................................................................................................ 24
1. FUNCTION KEY DEFINITIONS ................................................................................................................................................ 24
2. OSD CONTROL..................................................................................................................................................................... 24
3. FACTORY MODE INTRODUCTION........................................................................................................................................... 26
4. BURN-IN PATTERN................................................................................................................................................................. 27
5. AUTO COLOR BALANCE (AUTOMATICALLY CALIBRATE CHIPADC PARAMETER BY USING CHIP INTERNAL DAC.)................ 27
6. UPLOAD FIRMWARE TO MCU VIA VGACABLE .................................................................................................................... 27
7. AFTER REPAIR,TO ENSURE THE QUALITY YOU SHOULD DO THE FOLLOWING TEST AND ADJUSTMENT.................................... 27
CHAPTER 6- TROUBLE SHOOTING.............................................................................................................................................. 30
1. COMMON ACKNOWLEDGE .................................................................................................................................................... 30
2. NO POWER LED OFF............................................................................................................................................................ 30
3. POWER NORMAL LEDAMBER .............................................................................................................................................. 31
4. BACKLIGHT CAN’T BE TURNED ON........................................................................................................................................ 33
5. NO PICTURE BACKLIGHT ON............................................................................................................................................... 34
6. AT 32-GRAY SCALE PATTERN,COLOR LOST IN SOME SCALE ................................................................................................... 35
CHAPTER 7- RECOMMENDED PART LIST ................................................................................................................................. 35
ATTACHMENT 1- BILLOF MATERIAL......................................................................................................................................... 37
ATTACHMENT 2- SCHEMATIC....................................................................................................................................................... 47
ATTACHMENT 3- PCB LAYOUT..................................................................................................................................................... 60

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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:
zThis 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.
zUse only the specified power cord that comes with this monitor.
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 is high-voltage parts inside that may cause electric shock
to human bodies.
zStop using the monitor if the cabinet is damaged. Have it checked by a service technician.
zPut 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.
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
zWhen replacing parts on circuit boards, clamp the solder wires around terminals before soldering.
zKeep wires away from high voltage, high temperature components and sharp edges.
zKeep wires in their original position so as to reduce interference.
zAdjustment of this product please refers to the user’manual.
zUse 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
Block Diagram
There are 4pcs PCBA in this monitor, one is power& inverter board which is a single layer board, one is
interface board , one is keypad which is OSD control. The system function block diagram as below
This PWA is included switching power supplier, inverter for CCFL and interface board.(fig.1)
Lamp1
3
To Panel CCFL
To IF Board
AC Line Filter
ON/OFF Control
Power
MOSFET
Power
Transformer
Inverter Transformer
Photocoupler
MOSFET
+5V DC output
MOSFET
Snubber
&Schottky
2
Lamp4
INL833
AC Input
90V~264V
4
Brightness Control
Feedback
and OVP
Lamp2
PWM Control IC
LD7552B
Rectifier&
Filter
Circuit
+24V DC output
Snubber
&Schottky
Lamp3
Feedback
Control
1
Fig.1
INVERTER POWER

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Fig.2

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Electronic Circuit Theory
2.1. Inverter PWM circuit
Inverter Control circuit:(fig.2.1)
Fig.2.1
DC_5V through R7 and C2 will provide power for U1 on the pin11.
EN-ON/OFF voltage signal coming from scalar which is on IF BD will enable U1 to work. During start
up,appling a voltage level greater than 2V to ENA(pin16)enables the IC. A voltage less than 1V will disable
the IC.If no current is sensed approximately 2 seconds, U1 shuts off. R21 is used to limit current.C10 is
used to dump noise, C7 is used to soft start, and then the voltage on pin 16 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.
PWM duty cycle signal through R23 and C4 is on Pin 13(PWM), which adjusted will can change the
brightness of Panel.
The striking and operating frequency is determined by the external resistor (R17/R16 and C8)
connected to Pin 3 and Pin4.
DRV1 and DRV2 of U1 are used to drive Q6 and Q7 . DRV1 and DRV2 are controlled by build-in
PWM IC. Q6 and Q7 are switches which has two build-in N+P IGBTs.
The voltage signal on negative pole of ZD6/ZD7 sensed through R6/R19 comes to Pin14 of U1, ISEN
(Lamp Current Detection & Control). The CCFL current is detected through R6/R19 and reaches a regulated
value. The CCFL current detected at resistor R6/R19 is converted to a voltage level and input to the ISEN
pin.Once the lamps are ignited and the voltage at pin14(ISEN) is >0.7V,the IC enters the normal operating
mode and the PWM dimming control is activated.C5/C6/C14 is used to dump noise. Once the CCFLs are
ignited and current is sensed through resistor R6/R19 ,capacitor C5 performs the loop compensation
function. The voltage at IC pin2 controls the drive duty cycle of the power MOSFETs to regulate the CCFL
current. The control loop regulates the average current through the lamps by adjusting the overlap of the
output drives.
The transformer (T1) secondary winding leakage inductance and output capacitance(C25/C27) forms a
lower pass filter,which converts the square-wave driving signal into a sinusoidal output voltage signal for
CCFL.

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The over-voltage protection feature is implemented by using an extermal capacitor
devider(C1/C15/C16/C17) to sense the output voltage.The divide-down voltage signal is sent to the IC
Pin1(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. The voltage at the SSTCMP(pin2)rises rapidly because there is no current
feedback at ISEN(pin14).When the voltage at SSTCMP reaches a threshold of approximately 2V and ISEN
is less than 0.7V,a current source charges the capacitor(C3) connected to TIMER(pin12).Once the voltage
level at the TIMER pin reaches a threshold of approximately 3V,the drive outputs shut down and latch.To
resume operation,toggle the ENAsignal or restart VDDA.
Over-voltage and over-current protection are monitored by the voltage on VSEN(pin1).During normal
operation,if a CCFL is damaged or removed,the voltage at VSEN exceeds the user-defined, preset voltage
set by OVPT(pin15),the driver output duty cycle is regulated and the shutdown delay timer is
activated.OVPT sets the overall protection threshold voltage that is lower than3V(VSEN threshold. Once
the voltage at TIMER pin reaches 3V,the IC will shut down and latch. OVPT voltage setting is determined
by a resistor divider(R16/R8)connected to the OVPT.
2.2.Power PWM circuit
2.2.1 AC Input and EMI Filter:(fig.2.2.1)
R850
499K
F850
3.15A 250V
C850
222 Y2 L850
CHK-007
41 32
C851
222 Y2
R851
499K
C852
0.47uF X2
CN850
10A/250V
13
2
R852
499K
RT850
5R4A
fig.2.2.1
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,R851and R852 are joined between two inputting main circuit to
prevent man from shock. L850 is used to clear up low frequency wave. C850 and C851 are used to
discharge the waves that L850 produced. High frequency waves are damped by C852.
2.2.2 High Voltage to Low Voltage Control Circuit:(fig.2.2.2)
R842
499K
C875
472P
R844 47R
Q850
AP2761
2
13
Signal_GND
R843
499K
U850
LD7552B
1
45
2
83
7
6
GND
RTNC
COMP
OUTVCC
VCC
CS
D852
SF10-04
C854
100uF/450V
R853
27K
.
.
.
T850
SPW-115
5
8
6
7
3
1 1
2
1
1
9
1
0
Signal_GND
Signal_GND
D853
NC/P6KE200
Signal_GND
R848
100K 1%
C855
10uF/50V
R840
47R
D841
1N4148
C848
1nF/50V X7R
R884
10K
C849
0.01uF/50V X7R
Signal_GND
R862
0.2R 1W Fuse
C860
332 Y1
-+
D850
GBU4-06
3
1
2
4
R841
499K
C847
1nF/50V X7R
C846
47pF/50V NC
R859
0.43R/2W 1%
R854 27K
R855
27K
D851
FR10-10
R856
10R

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fig.2.2.2
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 highly integrated PWM controller. Typical start-up current for
U850 is only 20 uA, R841,R842 and R843 are serial circuit to limit current flow. When current flow
through R841,R842 and R843 gets to Pin 3 of U850, with VDD hold-up capacitor C855, U850 is enough
for starting up.
When U850 begins to work Pin8 of U830 will output square wave to drive Q850,and 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.At the same time, the current inducted by wires which connected
T850 Pin 5 and Pin 6, with components of D852, R856, C855 and C849, will be supplied to U850 for
normal operating.
When the sense voltage across the sense resistor R859, reaches the threshold voltage around 0.85V, the
output GATE drive will be turned off. Every time when the output of power supply is shorted or over loaded,
the FB voltage will increase, the build-in PWM output will then be turned off. Both will prevent the power
supply from being overheated under over loading condition. The PWM duty cycle is determined by this
current sense signal and VFB, the feedback voltage. The voltage feedback signal is provided from the
TL431 at the secondary side through the photo-coupler to the COMP pin of the LD7552B.
When the voltage on sense pin reaches Vcomp =(Vcomp-2Vf)/3, a switch cycle will be terminated
immediately. Vcomp is internally clamped to a variable voltage around 1.2 V for output power limit.The
LD7552B can be turned off by pulling COMP pin lower than 1.2V.The gate output pin of the LD7552B will
be disabled immediately under such condition .The off-mode can be released when the pull-low signal is
removed.
When Q850 are turned off, the main current flow will be consumed through D851, C875 R853,R854 and
R855. This will prevent Q850 from being damaged under large current impulse and voltage spike.
2.2.3 DC_24V and 5V Output Circuit and Feedback circuit:(fig.2.2.3)
fig.2.2.3