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EN7220 Service Manual




SERVICE MANUAL

17" LCD Monitor




THESE DOCUMENTS ARE FOR REPAIR SERVICE INFORMATION ONLY. EVERY REASONABLE
EFFORT HAS BEEN MADE TO ENSURE THE ACCURACY OF THIS MANUAL; WE CANNOT
GUARANTEE THE ACCURACY OF THIS INFORMATION AFTER THE DATE OF PUBLICATION
AND DISCLAIMS RE LIABILITY FOR CHANGES, ERRORS OR OMISSIONS.




Manufacture Date: Apr-09-04
EN7220 Service Manual


Table of Contents
Table of Contents ---------------------------------------------------------------------- 02

Revision List ---------------------------------------------------------------------------- 04

1. Monitor Specification --------------------------------------------------------------05
2. LCD Monitor Description ---------------------------------------------------------05

3. Operation Instructions -------------------------------------------------------------06

3.1 General Instructions -----------------------------------------------------------06

3.2 Adjusting The Picture ---------------------------------------------------------06

4. Input/Output Specification ------------------------------------------------------- 08

4.1 Input Signal Connector -------------------------------------------------------08

4.2 Factory Preset Display Modes ---------------------------------------------09

4.3 Power Supply Requirements -----------------------------------------------10

4.3.1 Input/Output Requirements --------------------------------------------10

4.3.2 Inverter Max Brightness ------------------------------------------------10

4.3.3 Inverter Min Brightness -------------------------------------------------10

4.4 Panel Specification (CPT EA02) --------------------------------------11

4.4.1 Display Characteristics -------------------------------------------------11

4.4.2 Optical Characteristics ------------------------------------------------12

4.4.3 Parameter guide line for CCFL Inverter -------------------------12

5. Block Diagram -----------------------------------------------------------------------13

5.1 Monitor Exploded View -----------------------------------------------------13

5.2 Software Flow Chart -----------------------------------------------------------14
EN7220 Service Manual

5.3 Electrical Block Diagram -----------------------------------------------------16
5.3.1 Scalar Board --------------------------------------------------------------16

5.3.2 Inverter/Power Board ---------------------------------------------------17

6. Schematic ----------------------------------------------------------------------------19

6.1 Scalar Board --------------------------------------------------------------------19

6.2 Inverter/Power Board ------------------------------------------------------21

6.3 Key Pad Board -----------------------------------------------------------------22

7. PCB Layout --------------------------------------------------------------------------24

7.1 Main Board ---------------------------------------------------------------------24
7.2 Inverter/Power Board --------------------------------------------------------25
7.3 Keypad Board -----------------------------------------------------------------25
8. Maintainability -----------------------------------------------------------------------26

8.1 Equipments and Tools Requirements -----------------------------------26

8.2 Trouble Shooting -------------------------------------------------------------27

8.2.1 Main Board -------------------------------------------------------------27

8.2.2 Power/Inverter Board --------------------------------------------------30

8.2.3 Key Pad Board ------------------------------------------------------------32
9. White-Balance, Luminance Adjustment ---------------------------------------33

10. EDID Content ----------------------------------------------------------------------34

11. BOM List ---------------------------------------------------------------------3549
EN7220 Service Manual
1. MONITOR SPECIFICATIONS
Driving system TFT Color LCD
LCD Panel Size 43.2cm(17.0")
Pixel pitch 0.264mm(H) x 0.264mm(V)
Viewable angle 140° (H) 130° (V)
Response time (typ.) 25 ms
Video Analog
Input Sync. Type H/V TTL
H-Frequency 30kHz ­ 80kHz
V-Frequency 55-75Hz
Display Colors Over 16 million Colors
Dot Clock 135MHz
Max. Resolution 1280 x 1024
Plug & Play VESA DDC2BTM
Power Consumption ON Mode <45W


OFF Mode <3W


Maximum Screen Size Horizontal : 13.3"(337.92mm)
Vertical: 10.6"(270.336mm)
Power Source 100~240VAC,47~63Hz

Environmental Operating Temp: 0°C to 40°C
Considerations Storage Temp. -20°C to 60°C
Operating Humidity: 15% to 90%

Weight (N. W.) Packaged 7.4Kgs Unit
Unpackaged 6.6Kgs Unit
EN7220 Service Manual
2. LCD MONITOR DESCRIPTION
The LCD MONITOR will contain a main board, an inverter/power board, keypad board and internal
adapter 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.



Monitor Block Diagram


Flat Panel and
CCFT Drive.
CCFL backlight




Power board
RS232 Connector
(include: adapter, inverter) Main Board
For white balance
adjustment in
factory mode
Keyboard



AC-IN
HOST Computer Video signal, DDC
100V-240V
EN7220 Service Manual
3. OPERATING INSTRUCTIONS
3.1 GENERAL INSTRUCTIONS
Press the power button to turn the monitor on or off. The other 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 Adjusting the Picture




The descriptions for function control LEDS
Main
Main Menu Sub Menu Sub Menu Adjust
Menu Description Reset Value
Item Item Icon Range
Icon
Recall Cool
Contrast Contrast from Digital-register. 0-100
Contrast Value
Luminance
Recall Cool
Brightness Backlight Adjustment 0-100
Brightness Value
Adjust Picture Phase to reduce
Focus 0-100 Do Auto Config
Horizontal-Line noise
Image Setup
Adjust picture Clock to reduce
Clock 0-100 Do Auto Config
Vertical-Line noise.
Adjust the horizontal position of
H. Position 0-100 Do Auto Config
Image the picture.
Position Adjust the vertical position of the
V. Position 0-100 Do Auto Config
picture.
Recall Warm Color Temperature The Color
Color Temp. Warm N/A N/A
from EEPROM. Temperature will
Recall Cool Color Temperature be set to Cool.
Cool N/A N/A
from EEPROM.
EN7220 Service Manual
The User R/G/B
User / Red Red Gain from Digital-register. 0-100
value (default is
User / 100) will not be
Green Gain Digital-register. 0-100
Green Modified by Reset
function.
User / Blue Blue Gain from Digital-register. 0-100

Yes Auto Adjust the H/V Position,
Auto Config N/A N/A N/A
Focus and Clock of picture.
(Analog-Onl
Do not execute Auto Config,
y Model) No N/A N/A N/A
return to main menu.
Adjust the horizontal position of
H. Position 0-100 50
the OSD.
Adjust the vertical position of the
OSD Setup V. Position 0-100 50
OSD.
OSD
Adjust the OSD timeout. 10-120 10
Timeout
Set OSD display language to
English N/A N/A
English.
Set OSD display language to
Deutsch N/A N/A
German.
Set OSD display language to
Français N/A N/A The Language
French.
Language will be set to
Set OSD display language to
Español N/A N/A English.
Spain.
Set OSD display language to
Italiano N/A N/A
Italian.
Set OSD display language to
N/A N/A
Simplified Chinese.
Show the resolution, H/V
Information Information N/A frequency and input port of N/A N/A
current input timing.
Clear each old status of
Yes N/A Auto-configuration and set the N/A N/A
Reset color temperature to Cool.
Do not execute reset, return to
No N/A N/A N/A
main menu.

Exit N/A N/A Exit OSD N/A N/A
EN7220 Service Manual
4. Input/Output Specification
4.1 Input Signal Connector

PIN NO. DESCRIPTION
DESCRIPTION PI N NO.

1. Red 9. +5V
2. Green 10. Detect Cable
3. Blue 11. NC
4. Ground 12. DDC-Serial Data
5. Ground 13. H-Sync
6. R-Ground 14. V-Sync
7. G-Ground 15. DDC-Serial Clock
8. B-Ground


VGA connector layout



1 5
6 10
11 15
EN7220 Service Manual
4.2 Factory Preset Display Modes
VESA MODES
Horizontal Vertical
Nominal Sync Nominal Sync Nominal
Frequenc Polarity Freq. Polarity Pixel
Mode Resolution Total y +/- 1 Hz Clock
+/- (MHz)
0.5kHz
640x480@60Hz 800 x 525 31.469 N 59.940 N 25.175
VGA 640x480@72Hz 832 x 520 37.861 N 72.809 N 31.500
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
SVGA
800x600@72Hz 1040 x 666 48.077 P 72.188 P 50.000
800x600@75Hz 1056x625 46.875 P 75.000 P 49.500
1024x768@60Hz 1344x806 48.363 N 60.004 N 65.000
1024x768@60Hz 1312x813 48.78 N 60.00 N 64.000
1024x768@70Hz 1328x806 56.476 N 70.069 N 75.000
XGA
1024x768@72Hz 1304x798 57.515 P 72.074 P 75.000
1024x768@75Hz 1328x804 60.200 N 74.90 N 80.000
1024x768@75Hz 1312x800 60.023 P 75.029 P 78.750
XGA 1152x864@75Hz 1600x900 67.50 P 75.000 P 108.000
1280x1024@60Hz 1688x1066 63.981 P 60.020 P 108.000
SXGA
1280x1024@75Hz 1688x1066 79.976 P 75.025 P 135.000
IBM MODES
Horizontal Vertical
Nominal
Nominal
Frequenc Nominal
Sync Sync Pixel
Mode Resolution Total y Freq.
Polarity Polarity Clock
+/- +/- 1 Hz
(MHz)
0.5kHz
DOS* 720x400@70Hz 900 x 449 31.469 N 70.087 P 28.322
DOS** 640x400@70Hz 800 x 449 31.469 N 70.087 P 25.175
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
EN7220 Service Manual
4.3 Power Supply Requirements
4.3.1 Input Requirements
INVERTER MAX BRINGTHNESS (Vadj: 5.0v), LOAD=120KX4(ROOM TEMPERATURE 25 ±4 )

ITEM SYMBOL MIN. TYP. MAX. UNIT REMARK
Vin
Input voltage 10.8 12 13.2 V

Input current Iin 2250 2500 mA FOR 4 LOAD

Output Current Iout 6.0 6.5 7.0 mA FOR 1 LOAD

Frequency FOR 1 LOAD
F 50.0 55.0 60.0 KHZ
Vopen
H.V open 1450 1600 1750 Vrms NO LOAD
Vload
H.V Load 710 810 910 Vrms RL=120K

Start voltage Vst 1650 1750 1850 Vrms RL=CCFL

Protect delay time PDT 0.4 1 4 Sec




4.3.2 Output Requirements
INVERTER MIN BRINGTHNESS (Vadj:0.0v), LOAD=120KX4(ROOM TEMPERATURE 25 ±4 )



ITEM SYMBOL MIN. TYP. MAX. UNIT REMARK
Vin
Input voltage 10.8 12 13.2 V

Input current Iin 660 750 mA FOR 4 LOAD

Output Current Iout 3.0 3.5 4.0 mA FOR 1 LOAD

Frequency FOR 1 LOAD
F 50.0 55.0 60.0 KHZ
Vopen
H.V open 1450 1600 1750 Vrms NO LOAD
Start voltage Vst 1650 1750 1850 Vrms RL=CCFL
Vload
H.V Load 350 450 550 Vrms RL=120K
EN7220 Service Manual
4.4 Panel Specification (CPT)
4.4.1 Display Characteristics
ITEM SPECIFICATION
Display Area (mm) 337.920(H) X270.336 (V) (17.0-inch diagonal)
Number of Pixels 1280(H) X1024 (V)
Pixel Pitch (mm) 0.264(H) X0.264 (V)
Color pixel Arrangement RGB vertical stripe
Display Mode Normally white, TN
Number of Colors 16.2M(6 Bit +FRC)
Brightness(cd/ ) 300 cd/ (Typ.)(Center point, Lamp current=7.0 mA)
Viewing Angle 140/130(Typ.)
Surface Treatment Anti-glare
Electrical interface LVDS, 2Ch
Total Module Power (W) 20.0(Typ.)
Optimum Viewing Angle 6 0'clock
Module Size (mm) 358.5(W) X296.5 (H) X17.0 (D)
Module Weight (g) 1800
Backlight Unit CCFL, 4 tables, edge-light (top*2/bottom*2)
4.4.2 Optical Characteristics
The optical characteristics are measured under stable conditions at 25 (Room Temperature)

ITEM SYMBOL CONDITION MIN TYP MAX UNIT

Contrast Ratio CR = =0 360 450 - -
Lumina Center L = =0 240 300 - cd/m²
nce Uniformity L = =0 20-
Response Time Tr - 9 - ms
= =0
(Black/White) Tf - 16 - ms
Image Sticking Tis 2 hours - - 2 sec
Horizontal ­75-75 ­85~85 -
CR 5
Viewing Vertical ­75-75 ­85~85 -
Angle Horizontal ­60~60 ­70~70 -
CR
Vertical ­55~55 ­65~65 -
Wx 0.283 0.313 0.343
White
Wy 0.299 0.329 0.359
Rx 0.607 0.637 0.667
Color Red
Ry 0.314 0.344 0.374
Coordin = =0 -
Gx 0.280 0.310 0.340
ates Green
Gy 0.552 0.582 0.612
Bx 0.113 0.143 0.173
Blue
By 0.070 0.100 0.130
EN7220 Service Manual
4.4.3 Parameter Guide for CFL Inverter


ITEM SYMBOL MIN TYP MAX UNIT REMARK
Lamp Voltage VL - 710 - V IL=6.0mA
Lamp Current IL 5.0 7.0 8.0 mA Note1
Inverter
FL 45 50 70 KHz Note2
Frequency
Starting Lamp 1350 - - V Tb=
VS
Voltage 1080 - - V Ta=25
Note3:IL=6.0mA
- 50,000 - hr
Continuous Operation
Lamp life time LT
IL=7.0mA
- 40,000 - hr
Continuous Operation
EN7220 Service Manual
5. Block Diagram
5.1 Monitor Exploded View
EN7220 Service Manual
5.2 Software Flow Chart

1




2 Y 3

N

4



5 N

Y

6



7 N 8

Y

9



10 N 11

Y

N 12 13 N

Y Y

14 15 N 16

Y

17



18 N 19

Y
EN7220 Service Manual



1) MCU initialize.
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.
Scaler initialize.
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?
EN7220 Service Manual
5.3 Electrical Block Diagram
5.3.1 Main Board
EN7220 Service Manual


5.3.2 Inverter/Power Board



Inverter Block Diagram
EN7220 Service Manual



Power Block Diagram
EN7220 Service Manual
6. Schematic
6.1 Main Board
VCC5V+
VCC5V


D2 SOT-223
VCC12V DIODE U201
R202 VCC2.5
VCC12V 6
RT9164-25CG
CON402(PITCH 2.54) 10K 1/16W 3 2
VI VO VCC2.5 4
CN201
GND ON_OFF R201 4.7K 1/16W




GND
GND 1 2 DIM C210 C211 + C212
VCC12V 3 4 VCC12V VCC5V
5 6




3
GND GND D201SCHOTTEYDIODE C201 R212 4.7K 1/16W 0.1uF 47uF/16V 0.1uF
VCC5V 7 8 VCC5V 1




1
GND 9 10 GND VCC5V+ onBACKLITE 6
0.1uF Q201
11 12 PMBS3904




2
VCPU
FB201 C
600 OHM
VCPU 6
B E
VCC5V 3,6
VCC5V
C202 C204
+ C203 + C205

R203 0.1uF 220uF/25V 0.1uF
1K 1/16W 220uF/25V


Brightness VCC3.3

R204
10K 1/16W VCC3.3 4
3




R205 4.7K 1/16W VCC5V+
1 Q202
4 AdjBACKLITE
PMBS3904
+ C206 TO-263
10uF/16V
U202 VAA1
2




C AIC1084-33M
3 2
VIN VOUT VAA1 4
B E
1
C214 ADJ C215 + C216 VAA2

VCC5V VLCD 0.1uF 47uF/16V 0.1uF
VAA2 4
VLCD 5
VAA3
VCC5V VCC3.3
R206 R208
VAA3 4
10K 1/16W 10K 1/16W VAA4
R209 R210
Q203
VAA4 4
AO3401 0 1/16W NC
3




R207 4.7K 1/16W
1 Q204
6 onPanel_5V/3.3V
PMBS3904
C207 + C208 R211
2




10uF/16V
0.1uF 10K 1/16W




CN301
RXD 6
DB15
TXD 6
11 1 FB301 0 1/16W R301 100 1/16W C304 0.047uF
RIN 4
6
12 2 FB302 0 1/16W R302 100 1/16W C305 0.047uF
GIN 4
7
13 3 FB303 0 1/16W R303 100 1/16W C306 0.047uF
BIN 4
8
14 4 R304 470 1/16W C307 0.001uF
1/16W




1/16W




SOG 4
R326




R327




9 PC5V R325 C301 C302 C303
15 5
10 VGA_CON 75 1/16W NC NC NC
75




75




R305 100 1/16W C308 0.047uF
GNDR 4
R306 100 1/16W C309 0.047uF
GNDG 4
R307 100 1/16W C310 0.047uF
GNDB 4
3




3




3




D301 D302 D303
BAV99 BAV99 BAV99 VCC5V

VCC5V
R308

10K 1/16W
2



1


2



1


2



1




R309 100 1/16W VCC5V PC5V
ST_DET1 6
2



1




HSI FB304 150 OHM R310 150 1/16W
HSY NC 4

VSI R312 100 1/16W R311 1K 1/16W D304
VSY NC 4
BAT54C-GS08

D319 D320 R313 C311 R314 C312 D317
3




MLL5232B 5.6V MLL5232B 5.6V MLL5232B 5.6V
2.2K 1/16W 33pF 10K 1/16W 220pF R317 R318 C313
10K 1/16W U301
10K 1/16W 8 1 0.1uF
7 VCC A0 2
CLK_DDC R315 100 1/16W 6 WP A1 3
DAT_DDC R316 100 1/16W 5 SCL A2 4
SDA GND

CN302 AT24C02N-10SC
D321 D318
4,6 DDC_DAT
25 MLL5232B 5.6V MLL5232B 5.6V
R 4,6 DDC_CLK
26
G 27 VCC5V DVI5V
B 29
RGB GND
2



1




28
HSY NC 8
VSY NC 15
SY NC GND 6 CLK_DDC2 R319 100 1/16W NC DVI5V D305
DDC SCL 7 DAT_DDC2 R320 100 1/16W NC R321 BAT54C-GS08 NC
DDC SDA 14 10K 1/16W NC
+5V 16 R322 100 1/16W NC
HPD ST_DET2 6
3




11
1/3shield 3 D314 D315 D316 C314 R323 R324 C315
2/4shield 19 LL5232B 5.6V 5% NCLL5232B 5.6V 5% NCLL5232B 5.6V 5% NC 10K 1/16W NC U302
0/5shield 22 0.1uF NC 10K 1/16W NC 8 1 0.1uF NC
clk shield 7 VCC A0 2
18 6 WP A1 3
DAT0+ B+ 4 SCL A2
17 5 4
DAT0- B- 4 SDA GND
10
DAT1+ G+ 4
9
DAT1- G- 4
2 AT24C02N-10SC NC
DAT2+ R+ 4
1
DAT2- R- 4
13
DAT3+ 12
DAT3- 5
DAT4+ 4
DAT4- 21
DAT5+ 20
DAT5- 23
clk+ CLK+ 4
24
clk- CLK- 4

JACK NC
D306 D307 D308 D309 D310 D311 D312 D313


NC NC NC NC NC NC NC NC
EN7220 Service Manual


VCC3.3 FB401 VPO