Envision EN-7220 User manual

EN7220 Service Manual
1
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

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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 (QDI L07) ----------------------------------------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

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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 ------------------------------------------------------22
6.3 Key Pad Board -----------------------------------------------------------------24
7. PCB Layout --------------------------------------------------------------------------25
7.1 Main Board ---------------------------------------------------------------------25
7.2 Inverter/Power Board --------------------------------------------------------26
7.3 Keypad Board -----------------------------------------------------------------26
8. Maintainability -----------------------------------------------------------------------27
8.1 Equipments and Tools Requirements -----------------------------------27
8.2 Trouble Shooting -------------------------------------------------------------28
8.2.1 Main Board -------------------------------------------------------------28
8.2.2 Power/Inverter Board --------------------------------------------------31
8.2.3 Key Pad Board ------------------------------------------------------------33
9. White-Balance, Luminance Adjustment ---------------------------------------34
10. EDID Content ----------------------------------------------------------------------35
11. BOM List ---------------------------------------------------------------------36～50

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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
Considerations
Operating Temp: 0°C to 40°C
Storage Temp.: -20°C to 60°C
Operating Humidity : 15% to 90%
Weight (N. W.) Packaged 7.4Kgs Unit
Unpackaged 6.6Kgs Unit

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2. LCD MONITOR DESCRIPTION
The LCD MONITOR will contain an 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.
Power board
(
include:ada
p
ter,inverter
)
)
Flat Panel and
CCFL backlight
Main Board
Keyboard
RS232 Connector
For white balance
adjustment in
factory mode
HOST Computer
CCFT Drive.
AC-IN
100V-240V Video signal, DDC
Monitor Block Diagram

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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 Menu
Item
Main
Menu
Icon
Sub Menu
Item
Sub Menu
Icon Description Adjust Range Reset Value
Contrast Contrast from Digital-register. 0-100 Recall Cool
Contrast Value
Luminance Brightness Backlight Adjustment 0-100 Recall Cool
Brightness Value
Focus
Adjust Picture Phase to reduce
Horizontal-Line noise 0-100 Do Auto Config
Image Setup Clock
Adjust picture Clock to reduce
Vertical-Line noise. 0-100 Do Auto Config
H. Position
Adjust the horizontal position of
the picture. 0-100 Do Auto Config
Image
Position V. Position Adjust the vertical position of the
picture. 0-100 Do Auto Config
Warm N/A
Recall Warm Color Temperature
from EEPROM. N/A
Color Temp.
Cool N/A
Recall Cool Color Temperature
from EEPROM. N/A
The Color
Temperature will
be set to Cool.

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User / Red Red Gain from Digital-register. 0-100
User /
Green Green Gain Digital-register. 0-100
User / Blue Blue Gain from Digital-register. 0-100
The User R/G/B
value(default is
100) will not be
Modified by Reset
function.
Yes
N/A Auto Adjust the H/V Position,
Focus and Clock of picture. N/A N/AAuto Config
(Analog-Onl
y Model) No N/A
Do not execute Auto Config,
return to main menu. N/A N/A
H. Position
Adjust the horizontal position of
the OSD. 0-100 50
V. Position
Adjust the vertical position of the
OSD. 0-100 50
OSD Setup
OSD
Timeout Adjust the OSD timeout. 10-120 10
English N/A
Set OSD display language to
English. N/A
Deutsch N/A Set OSD display language to
German. N/A
Français N/A Set OSD display language to
French. N/A
Español N/A Set OSD display language to
Spain. N/A
Italiano N/A
Set OSD display language to
Italian. N/A
Language
简体中文 N/A Set OSD display language to
Simplified Chinese. N/A
The Language
will be set to
English.
Information Information N/A
Show the resolution, H/V
frequency and input port of
current input timing.
N/A N/A
Yes N/A
Clear each old status of
Auto-configuration and set the
color temperature to Cool.
N/A N/A
Reset
No N/A
Do not execute reset, return to
main menu. N/A N/A
Exit N/A N/A Exit OSD N/A N/A

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4. Input/Output Specification
4.1 Input Signal Connector
PIN NO.
DESCRIPTION PI N NO.
DESCRIPTION
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
15
610
11 15

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4.2 Factory Preset Display Modes VESA MODES
Horizontal Vertical
Mode Resolution Total
Nominal
Frequenc
y
+/-
0.5kHz
Sync
Polarity
Nominal
Freq.
+/- 1 Hz
Sync
Polarity
Nominal
Pixel
Clock
(MHz)
640x480@60Hz 800 x 525 31.469 N 59.940 N 25.175
640x480@72Hz 832 x 520 37.861 N 72.809 N 31.500
VGA
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
800x600@72Hz 1040 x 666 48.077 P 72.188 P 50.000
SVGA
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
1024x768@72Hz 1304x798 57.515 P 72.074 P 75.000
1024x768@75Hz 1328x804 60.200 N 74.90 N 80.000
XGA
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
Mode Resolution Total
Nominal
Frequenc
y
+/-
0.5kHz
Sync
Polarity
Nominal
Freq.
+/- 1 Hz
Sync
Polarity
Nominal
Pixel
Clock
(MHz)
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

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4.3 Power Supply Requirements
4.3.1 Input Requirements
INVERTER MAX BRINGTHNESS (Vadj:5.0v), LOAD=120KΩX4(ROOM TEMPERATURE 25℃±4℃)
ITEM SYMBOL MIN. TYP. MAX. UNIT REMARK
Input voltage Vin 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 F 50.0 55.0 60.0 KHZ FOR 1 LOAD
H.V open Vopen 1450 1600 1750 Vrms NO LOAD
H.V Load Vload 710 810 910 Vrms RL=120KΩ
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=120KΩX4(ROOM TEMPERATURE 25℃±4℃)
ITEM SYMBOL MIN. TYP. MAX. UNIT REMARK
Input voltage Vin 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 F 50.0 55.0 60.0 KHZ FOR 1 LOAD
H.V open Vopen 1450 1600 1750 Vrms NO LOAD
Start voltage Vst 1650 1750 1850 Vrms RL=CCFL
H.V Load Vload 350 450 550 Vrms RL=120KΩ

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4.4 Panel Specification (QDI L07)
4.4.1 Display Characteristics
PARAMETER SPECIFICATION UNIT
Display Size 43(17") Diagonal cm
Active area 337.9(H) x 270.3(V) mm
1280(H) x 1024(V) pixel
Pixel format (1 Pixel=R+G+B dots)
Pixel pitch 0.264(H) x 0.264(V) mm
Pixel configuration R, G, B vertical stripe
Display mode Normally White
Unit outline dimensions (typ.)*1 358.5 x 296.5x 16.5 mm
weight 1970(Max.) g
Surface treatment Anti-glare and hard-coating 3H
Low reflection (~ 5%)
Lamp Quantity 4 pcs
4.4.2 Optical Characteristics
The optical characteristics are measured under stable conditions at 25℃(Room Temperature)：
Parameter Symbol Condition Min Typ. Max. Unit Remark
Horizontal θ21, θ22 65 75 Deg
θ11 55 65 Deg
Vertical
θ12
CR>10
50 60 Deg
Horizontal θ21, θ22 85 Deg
θ11 75 Deg
Viewing angle
range
Vertical
θ12
CR>5
70 Deg
Note1,4
Contrast ratio CR θ=0° 300 450 — Note2, 4
Response time t θ=0° — 20 ms
Rise time tr 4 ms
Fall time td 16 ms
Note3, 4
Wx 0.283 0.313 0.343
Chromaticity of White(CIE 1931)
Wy 0.299 0.329 0.359
Rx 0.603 0.633 0.663
Chromaticity of Red(CIE 1931)
Ry 0.306 0.336 0.366
C
hromaticity of Green(CIE 1931) Gx 0.270 0.300 0.330
Note4

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Gy 0.556 0.586 0.616
Bx 0.116 0.146 0.176
Chromaticity of Blue(CIE 1931)
By 0.073 0.103 0.133
Luminance of white
Note 4[Note 4] YL 240 300
cd/㎡
IL=7.0
mArms
White Uniformity δw — 1.25 1.33 Note5
Cross talk 1.50% Note6
4.4.3 Parameter Guide for CFL Inverter
The backlight system is an edge-lighting type with 2- CCFL(Cold Cathode Fluorescent Lamp).
The characteristics of four lamps are shown in the following tables.
PARAMETER SYMBOL MIN TYP MAX UNIT REMARK
Lamp current range IL3.0 7.0 8.0 mArms Note1
Lamp voltage VL 725 Vrms
Lamp power consumption PL 5.1 W Note2 IL=7.0mA
Lamp frequency FL 52 kHz Note3
1100 Vrms Ta=25 ℃
Established starting voltage Vs 1420 Vrms Ta = 0℃Note4
Lamp life time LL40000 50000 hour Note5

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5. Block Diagram
5.1 Monitor Exploded View

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5.2 Software Flow Chart
1
2
N
Y
5
Y
N
10
Y
N
12
Y
N
7
Y
N
6
4
3
8
9
14
11
13
Y
N
1
5
Y
N
16
1
7
19
Y
N
18

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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 life time of back light.
12) Check the analog port, are there any signals coming ?
13) Does the scalar send out a 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 afte
r
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 ?

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5.3 Electrical Block Diagram
5.3.1 Main Board

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5.3.2 Inverter/Power Board
Inverter Block Diagram

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Power Block Diagram

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6. Schematic
6.1 Main Board
715L1203-1
VAA1
B1
3.INPUT
RIN
GIN
BIN
VSYNC
GNDR
GNDG
GND B
ST_DET1 HSYNC
SOGDDC_CLK
DDC_DAT
ST_DET2
R+
R-
G-
G+
B+
B-
CLK+
CLK-
TXD
RXD
VCC5V
VLCD
B2
4.SCALER
RIN
GIN
SOG
BIN
GND R
GND G
GND B
HSYNC
VSY NC
R+
R-
G-
G+
B+
B-
CLK+
CLK-
CSZ
SCL
SDA
HWRESET
INT
Volume
AdjBACKLITE
PA[0..9]
PB[0..9]
VCC2.5
VCC3.3
VAA1
VAA2
VAA3
VAA4
AD0
AD1
AD2
AD3
B4
2.POWER
onPanel_5V/3.3V
onBACKLITE
AdjBACKLITE
VCC3.3
VCC2.5
VAA1
VAA2
VAA3
VAA4
VCC5V
VCC12V
VLCD
VCPU
VCC12V
VAA4
PA[0..9]
VAA4
PB[0..9]
VAA3
VCPU
MST8111B SCHEMATIC
VCC12V
VCC2.5
B5
5.PANEL INTERFACE
VLCD
PB[0..9]
PA[0..9]
VAA2
VCC5V
VCC3.3
B3
6.MCU
onBACKLITE
ST_DET2
onPANEL_5V/3.3V
SDA
INT
CSZ
DDC_DAT
ST_DET1
SCL
HWRESET
DDC_CLK
Volume
VCC5V
VCC12V
VCPU
RXD
TXD
AD0
AD1
AD2
AD3
VCC 3. 3
VAA3
VCPU
VAA1
VLCD
VCC2.5 VAA2
U201
RT9164-25CG
3 2
1
VI VO
GND
VAA4
VCC5V+
SOT-223
onBACKLITE 6
D202
GS1D
Q204
PMBS3904
32
1
VCC3.3
C210
0.1uF
VAA1
+
C202
220uF/25V
DIM
R205 4.7K 1/16W
onPanel_5V/3. 3V6
R204
10K 1/16W
VAA4 4
+ C211
47uF/16V
VCC2.5 4
VCC5V+
GND Q201
PMBS3904
32
1
VAA2
R202
10K 1/16W
R212 4.7K 1/16W
GND
GND
R208
10K 1/16W
VCC12V
R209
0 1/16W
C207
0.1uF
VLCD
VAA3
VCC5V
ON_OFF
C201
0.1uF
VCC12V 6
VCC5V
VCPU 6
FB201
600 OHM
R206
10K 1/16W
VCPU
VAA3 4
R207 4.7K 1/16W
AdjBAC KLI TE4
Q203
AO3401
+ C206
1uF/0805
Brightness
VCC2.5
Q202
PMBS3904
32
1
+ C215
47uF/16V
D201 SS14
VCC5V
C214
0.1uF
VCC3.3
GND
TO-252
R210
NC
VCC5V+
C212
0.1uF
GND
C203
0.1uF
C205
0.1uF
R201 4.7K 1/16W
+ C208
10uF/16V
VCC5V
C216
0.1uF
VCC3.3 4
VCC5V
VCC12V
+
C204
220uF/25V
VLCD 5
VCC5V
CN201
CON402(PITCH 2.00)
1
3
5
7
9
11
2
4
6
8
10
12
VAA1 4
VCC12V
VAA2 4
VCC5V
R203
1K 1/16W
U202
AIC1084-33CE
3
1
2
VIN
ADJ
VOUT
GND
R211
10K 1/16W
VCC5V 3,6

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D307
NC
BIN 4
C314
NC
B- 4
U302
NC
1
2
3
45
6
7
8A0
A1
A2
GNDSDA
SCL
WP
VCC
GNDG 4
R317
10K 1/16W
D308
NC
R- 4
DAT_DDC
D316
NC
C310 0.047uF
R318
10K 1/16W
D305
NC
3
1 2
HSI
DVI5V
R306 100 1/16W
R309 100 1/16W
GNDR 4
G+ 4
R313
2.2K 1/16W
DAT_DDC2
VCC5V
D314
NC
D317
MLL5232B 5.6V
R+ 4
VCC5V
D306
NC
R303 100 1/16W
R302 100 1/16W
VSI
CN302
NC
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
VSY N C
R
HSYNC
DAT1-
DAT1+
1/3shield
DAT3-
DAT3+
+5V
SYNC GND
HPD
G
RGB GND
DAT0-
DAT0+
0/5shield
DAT5-
DAT5+
clk shield
clk+
clk-
B
R307 100 1/16W
D313
NC
DVI5V
R326
75 1/16W
CLK+ 4
VSY N C 4
PC5V
C313
0.1uF
FB303 0 1/16W
D312
NC
R304 470 1/16W
D301
BAV99
3
1 2
C311
33pF
D315
NC
D319
MLL5232B 5.6V
VGA_CON
D309
NC
ST_DET2 6
GIN 4
CLK- 4
VCC5V
D318
MLL5232B 5.6V
C307 0.001uF
FB302 0 1/16W
B+ 4
CLK_DDC2
CN301
DB15
1
6
2
7
3
8
4
9
5
11
12
13
14
15
10
D310
NC
D321
MLL5232B 5.6V
SOG 4
VCC5V
FB301 0 1/16W
TXD 6
C312
220pF
R310 150 1/16W
R320 NC
R315 100 1/16W
R301 100 1/16W
R323
NC
R325
75 1/16W
R322 NC
R316 100 1/16W
D303
BAV99
3
1 2
RXD 6
R308
10K 1/16W
R324
NC
D302
BAV99
3
1 2
R311 1K 1/16W
HSYNC 4
C306 0.047uF
R305 100 1/16W
R312 100 1/16W
DDC_CLK6
R321
NC
C303
NC
U301
AT24C02N-10SC
1
2
3
45
6
7
8A0
A1
A2
GNDSDA
SCL
WP
VCC
C315
NC
D304
BAT54C-GS08
3
1 2
C309 0.047uF
D311
NC
R319 NC
C302
NC
R327
75 1/16W
C305 0.047uF
FB304 150 OHM
ST_DET1 6
DDC_DAT6
C308 0.047uF
PC5V
RIN 4
R314
10K 1/16W
D320
MLL5232B 5.6V
C304 0.047uF
GNDB 4
G- 4
CLK_DDC
C301
NC