CTX S720G User manual

S720G
SERVICE MANUAL
The Monitor S
p
ecialists EDITION 1
Aug.. 2003

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TABLE OF CONTENTS
CONTENTS PAGE
Sections
1. Scope 3
2. Input requirements 4
3. Electrical Characteristics 5
4. Trouble Shooting 10~11
5. System Block Diagram 12
6. Inverter Board I/O Connection 13
7. IC Pin Configuration 14~15
8. Pin Assignment 16~25
9. Parts List 26
Appendix
1. Main Board Circuit Diagram
2. Assembly Explosion Drawing

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Copyright © 2003 by Chuntex Electronic Co., Ltd.
The CTX SERVICE MANUAL is published by Chuntex Electronic Co., Ltd
All rights reserved. No part of this manual may be used, copied, reproduced, or transmitted in any form or by
any means for any purpose without the express written permission of the publisher.
The publisher has been trying its best to make this publication perfect, and in this manner takes no
responsibility for the use of any of the materials or methods described in this manual, or for the products
thereof. Neither will the publisher be responsible for any damages caused by misuse or misquotation.
Information in this manual is subject to change by the publisher without any notice in advance.
CTX is a registered trademark of Chuntex Electronic Co., Ltd.

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1. SCOPE
This specification defines the design and performance requirements for the 17” SXGA TFT
LCD display monitor.S720G
Feature Description
1 Universal input AC/DC power supply inside the monitor
2 Analog RGB interface (VGA ) 30~80KHz, 59~75Hz, 135MHz
3 Digital Visual interface(DVI-D) TMDS 1 Channel 165 MHz
4 17” SXGA 1280*1024, TFT LCD panel
5 Function ke
y
s * 5 : Power On/Off, ESC, △
(
u
p)
, ▽
(
down
)
,
(
enter
)
6 Direct Acess function keys : △for contrast function, ▽for brightness function , ESC
for audio mute function
7 Green/Amber LED indicator for power on/power saving
8 Plug & play support with DDC2B protocol installed.
9 Power saving mode compliant with Energy Star
10 OSD (on screen display) MENU operation
10.1 Brightness adjustment
10.2 Contrast adjustment
10.3 Auto tune function (VGA)
10.4 Color selection
10.5 Image adjustment
10.6 Position adjustment
10.7 Language selection
10.8 Reset function
10.9 Source selection(DVI/VGA)
10.10 1W * 2 Audio function inside the monitor
11 Volume adjust by OSD
12 OSD information of input status
2. INPUT REQUIREMENTS
2.1 Input Power
2.1.1. Power Source 100 ~ 240 Vac, + -10%, 50/60 Hz
2.1.2. Power Consumption
2.1.3. AC Line Drop Out
2.1.4. AC Wave Distortion
2.1.5. In-rush Current
2.1.6. Power Cord
Normal operating mode
Audio function is operating at max output: ≦39W
w/o audio function : ≦35W
Power saving mode
Audio function is operating at max output: ≦7W
w/o audio function : ≦2W
Power switch off : ≦1.5W
Picture must not disappear while AC 100 V input drop out(10ms, 100%)
10% max. permitted
50 A max at 240 Vac cold start
Detachable, 3P with ground type.

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2.2 Display Input
2.2.1. Analog Input RGB Video
2.2.1.1 Sync Signal
Analogue, 0.0 to 0.7 V peak to peak
Separate RGB
Input impedance 75 Ohm
Positive polarity
Separate horizontal & vertical sync (3.3V & 5V)
Low level 0.8 V maximum
High level 2.0 V minimum
Positive or negative polarity
Analog Input Connection a. Detachable Mini D-sub 15 pin male in two ends signal
cable , length 1.8M.
b. A female Mini D-sub 15 pin base.
Pin 1 Red
Pin 2 Green
Pin 3 Blue
Pin 4 No Connection
Pin 5 Ground
Pin 6 R Return
Pin 7 G Return
Pin 8 B Return
Pin 9 DDC +5V
Pin 10 Ground
Pin 11 Ground
Pin 12 SDA
Pin 13 H. Sync
Pin 14 V. Sync
Pin 15 SCL
2.2.2 Digital Input
Input Interface DVI-D V.1 TMDS 165MHz 1-Channel
Digital Input connection a. Captive cable (length 1.5M) in LCD monitor end ,
DVI-D male
connector in another end.
b. Cable pin assignment
2.3 Audio Input
2.3.1 Audio Input Signal Right &Left channels.
Input level : 1Vrms(typ), 2Vrms(max)
Input Impedance : 15Kohm
2.3.2 Audio Input Connection a. Detachable stereo phone head in two ends signal
cable.
b. A female stereo phone jack base.
DVI-D 1-Channel Pin Assignment
Pin
Signal Assignment
Pin
Signal Assignment
Pin
Signal Assignment
1
T.M.D.S Data 2
-
9
T.M.D.
SData1
-
17
T.M.D.S Data 0
-
2
T.M.D.S Data 2
+
10
T.M.D.S Data 1
+
18
T.M.D.S Data 0
+
3
T.M.D.S Data 2 Shield
11
T.M.D.S Data 1 Shield
19
T.M.D.S Data 0 Shield
4
NC
12
NC
20
NC
5
NC
13
NC
21
NC
6
DDC Clock
14
+
5V Power
22
T.M.D.S. Clock Shield
7
DDC D
ata
15
Ground
23
T.M.D.S. Clock
+
8
NC
16
Hot Plug Detect
24
TMDS Clock

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3. ELECTRICAL CHARACTERISTICS
3.1 LCD Panel
3.1.1. Type 17” diagonal, SXGA resolution, color TFT-LCD
3.1.2. Pixel structure R/G/B sub-pixels in vertical stripes
1280 x 1024 array matrix
a-Si TFT active matrix
3.1.3. Gray scale 16 million colors.
3.1.4. Surface treatment 3H hard coating ,anti-static,anti-glare
3.1.5. Backlight
3.1.6 Pixel Faults
Integral CCFL, type to support field replacement.
Life time 30000 hours @ 25C, 50% of initial value.
Model
Project
Pixel Faults type
S730G
S720G
LIS17G24KC01
LIS17S24KC01
Type Bright Pixels (Note 1) ≦5
Type Dark Pixels (Note 2) ≦5
Type Fault Pixels / Sub-Pixels(Note 3) ≦3
Type Cluster of type1 or type 2 faults(Note ≦2
Type Cluster of type3 faults (Note4) ≦3
Type Total Pixel Faults ≦8
Note 1 : Bright pixels in full black pattern.
Note 2 : Dark pixels in full white pattern
Note 3 : fault Pixel / Sub-Pixel : The pixel or sub-pixel is abnormal but not bright/dark pixel.
Note 4 : Fault Cluster : Two or more Pixels/Sub-pixels with faults within 5 * 5 block of pixels.
3.2 Modes and Timing Comparability
3.2.1Analog Input Supported Timing VESA Standard mode :
Display Format IBM VGA VESA VESA VESA VESA VESA
Horizontal Dots 720 640 640 640 800 800 800
Vertical lines 400 480 480 480 600 600 600
Horizontal Frequency 31.469 37.861 37.5 37.879 48.077 46.875
Vertical Frequency ( Hz ) 70 59.94 72.809 75 60.317 72.188 75.000
Pixel Rate ( MHz ) 28.322 25.175 31.5 31.5 40 50 49.5
H. Sync. Polarity - - - - + + +
A
μ
S
(Period)
31.778 26.413 26.667 26.4 20.8 21.333
B
μ
S
(PulseWidth)
3.813 1.270 2.032 3.2 2.4 1.616
C
μ
S
( Back Porch )
1.907 4.063 3.810 2.2 1.28 3.232
D
μ
S
(ActiveArea)
25.422 20.317 20.317 20.0 16.0 16.162
E
μ
S
(Front Porch )
0.636 0.763 0.508 1.00 1.12 0.323
V. Sync. Polarity + - - - + + +
O ms ( Period ) 16.683 13.735 13.333 16.579 13.853 13.333
P ms ( Pulse Width ) 0.064 0.079 0.080 0.106 0.125 0.064
Q
(B kP h)
1048
0739
0427
0607
0 478
0448

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Timing Chart
Display Format VESA VESA VESA VESA VESA VESA
Horizontal Dots 1024 1024 1024 1152 1280 1280
Vertical lines 768 768 768 864
1024 1024
Horizontal Frequency 48.363 56.746 60.023 67.5 63.981 79.976
Vertical Frequency ( Hz ) 60.004 70.069 75.029 75 60.013 75.025
Pixel Rate ( MHz ) 65.0 75 78.75 108 108 135
H. Sync. Polarity - - + + + +
A
μ
S
(Period)
20.667 17.707 16.660 14.815 15.631 12.054
B
μ
S
(PulseWidth)
2.092 1.813 1.219 1.185 1.180 1.067
C
μ
S
( Back Porch )
2.462 1.920 2.253 2.370 2.065 1.837
D
μ
S
(ActiveArea)
15.754 13.653 13.003 10.667 11.797 9.481
E
μ
S
(Front Porch
)
0.369 0.321 0.203 0.593 0.590 0.119
V. Sync. Polarity - - + + + +
O ms ( Period ) 16.666 14.272 13.238 13.333 16.663 13.329
P ms ( Pulse Width ) 0.124 0.106 0.050 0.044 0.047 0.038
Q ms ( Back Porch ) 0.6 0.513 0.466 0.474 0.594 0.475
R ms ( Active Area ) 15.88 13.599 12.795 12.8 16.006 12.804
S ms ( Front Porch ) 0.062 0.054 0.017 0.015 0.016 0.012

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Figure. 1 Timing Chart
Video
H Sync.
B C D E
A
Video
3.2.2 Digital Input
DVI Support mode
640 * 480 @60Hz
800 * 600 @60Hz
1024*768 @60Hz
1280*1024@60Hz
3.3 Plug & Play DVI support VESA DDC 2B+ standard
DDC 2B data transmission only for I2C BUS interface card.
3.4 Scanning characteristics VGA DVI(DDC description) DVI(Input signal range)
Horizontal frequency 30KHz to 80KHz 30KHz to 66KHz 30KHz to 80KHz
Refresh rate 59Hz to 75Hz 59Hz to 61Hz 59Hz to 75Hz
3.5 Audio Module
3.5.1. Type : Stereo BTL audio output amplifier with DC volume control
with two 1W speakers.
3.5.2. Input Level : 1Vrms
3.5.3. Output Power: 1W * 2 (10% THD, 1KHz)
3.5.4. Total Harmonic Distortion (THD) : 0.3% (Typ.) (0.5W * 2, 1KHz)
3.5.5. Frequency Response ±3dB : 450Hz ~ 20KHz
3.5.6. Channel unbalance (output power): 1dB (max.)

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3.6 User Controls and Indicator
3.6.1 Power ON/OFF Switch
3.6.2 LED Indicator
3.6.3 OSD
3.6.3.1 Buttons
3.6.3.2 OSD Menu Level
3.6.4 Hot Keys Function
3.6.4.1 Contrast ( )
3.6.4.2 Brightness ( )
The switch control scaler power down and turn off panel.
The LED color shall indicate power status as shown in paragraph
3.7
ESC ,▽, △,
See Table 2. S730G/S720G OSD Control Map
Press “△” to pop up ;then press “△” or “▽” to adjust Contrast up
or down.
Press “▽” to pop up ;then press “△” or “▽” to adjust Brightness
up or down.
*3.6.4.3 Mute On ( )
*3.6.4.4 Mute Off ( )
*3.6.4.5 In monitor power saving mode
Press “Esc” directly to disable speakers, while speakers in normal
state.
Press “Esc” directly to enable speakers, while speakers in audio
mute state.
“Esc” key is for Mute On and Off function
“△” key is for increasing volume function.
“▽” key is for decreasing volume function.
“ESC” key is enable or disable audio mute.
*3.6.4.6 Key lock function Push” “ for 10 sec while the screen has no any OSD showing to
Setup “Key lock” functions enable or disable.
Table 2 S720G/S730G OSD Control Map
Level 1 Level 2 Level 3 Level 4
Direct Adj. Brightness
Direct Adj. Contrast
Direct Adj. Audio Mute
Volume Adjustment Scale
*Auto Tune *Adjustment Scale
9300∘K
6500∘K
Color
User R/G/B select Adjustment Scale
*Clock *Adjustment Scale
*Phase *Adjustment Scale
Image
Smooth On/Off
Main Menu
*
Image Position
*H-Position *Adjustment Scale

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*V-Position *Adjustment Scale
*Center *Adjustment Scale
H-Position Adjustment Scale
V-Position Adjustment Scale
OSD Position
Center Adjustment Scale
English (select)
Deatsch (select)
French (select)
Spanish (select)
Italiano (select)
Language
中文 (option)
Reset Yes/No
Source DVI/VGA
*Function is disable in DVI mode.
3.6.5 Accessory OSD Indications
Signal out of range An input signal which is outside the range defined in
Section 3.4 shall cause the monitor to display a message
Signal Out of Range.
No Signal Input , Input Source
“auto detecting” and power down.
When the signal cable is not plugged into PC or when the
horizontal or vertical sync are absent and when the
monitor is turned on. After 5 sec isn’t to detect H or V Sync
then show “No Signal Input” for 3 seconds then show”Auto
detecting” message on the OSD for 2seconds,( if first turn
on the monitor that will show it around 27 seconds.), and
then show ” Power down” message on screen 2 sec.And
then the monitor shall go to power saving status.

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3.7 Power Management
This monitor will meet the low power specification, Including USA governmental requirements
For Energy Star, the NUTEK standard and the VESA DPMS standard which detected the Hori. /Vert.
Sync signal from host CPU.
A dual color (green/amber) LED is located on the front bezel to indicate the power management states.
Status
Sync. Video
Power
consumption
Power
management Picture Recovery time LED Color
Active Active 39W max. On - Green
No Sync. Blanked ≦2W
(Note.1)
Power saving ≦3 sec Amber
Note. 1 : Audio function is operating at no signal input.
Once “Esc” or “△” or “▽” key initiates under power saving condition, the audio
function can be waked up and the power consumption can not be the above definition.
4. TROUBLE SHOOTING
VIDEO DOES NOT APPEAR

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R.G.B is not displayed correctly

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5. SYSTEM BLOCK DIAGRAM

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6. inverter board I/O connections

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7. IC PIN CONFIGURATION

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8. PIN ASSIGNMENT MAIN/BOARD

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TEST CONDITION : AC LINE IN: 110V/60Hz
PATTEN:FULL WHITE
Uint:Volt
640*480 31K/60Hz 0 3.28 0.03 3.38 3.37 2.77 0 0.01 0.75
1024*768 60K/75Hz 0 3.27 0.03 3.38 3.37 2.77 0 0.01 0.75
1280*1024 80K/75Hz 0 3.28 0.03 3.38 3.37 2.77 0 0.01 0.75
DVI1280*1024 64K 0 3.27 0.03 3.38 3.37 2.76 0 0.01 0.75
640*480 31K/60Hz 2.00 1.96 1.28 3.38 0.06 3.38 3.38 3.38 2.77
1024*768 60K/75Hz 2.00 1.96 1.28 3.38 0.06 3.38 3.38 3.39 2.78
1280*1024 80K/75Hz 2.00 1.96 1.28 3.38 0.06 3.38 3.38 3.39 2.78
DVI1280*1024 64K 2.00 1.96 1.28 3.38 0.07 3.38 3.38 3.38 2.77
640*480 31K/60Hz 0 0.06 0.68 0 11.19 0.01
1024*768 60K/75Hz 0 0.06 0.68 0 11.19 0.02
1280*1024 80K/75Hz 0 0.06 0.68 0 11.19 0.02
DVI1280*1024 64K 0 0.06 0.68 0 11.18 0.01
640*480 31K/60Hz 3.38 3.38 0 3.38 3.33 4.84 4.85 1.02 1.63 1.01
1024*768 60K/75Hz 3.38 3.38 0 3.38 3.33 4.84 4.85 0.80 1.85 0.80
1280*1024 80K/75Hz 3.38 3.38 0 3.38 3.33 4.84 4.85 0.80 1.85 0.80
DVI1280*1024 64K 3.38 3.38 0 3.38 3.33 5.01 5.01 0 0.09 0
640*480 31K/60Hz 3.30 1.85 2.09 2.43 0.09 2.26 2.49 1.99 0.79 3.38
1024*768 60K/75Hz 3.29 1.61 1.70 2.55 0.09 2.49 2.61 2.16 0.65 3.38
1280*1024 80K/75Hz 3.30 1.85 1.70 2.55 0.09 2.49 2.68 2.16 0.65 3.38
DVI 1280*1024 64K 0 0 0 0.01 0.01 3.00 0 0 0 3.38
IC Q7(2N3904) Q634(MMBT3906LT1) Q635(2N3904)
PIN
MODE E C B E C B E C B
IC Q636(3906) Q637(3906) Q638(3906)
PIN
MODE E C B E C B E C B
IC Q639(2N3904) Q641(2N3904)
PIN
MODE E C B E C B E C B
IC U4(GM5120)
PIN
MODE 1 2 3 4 5 6 7 8 9 10
IC U4(GM5120)
PIN
MODE 11 12 13 14 15 16 17 18 19 20

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640*480 31K/60Hz 0 2.50 1.38 1.56 1.45 2.45 0 2.43 3.00 3.59
1024*768 60K/75Hz 0 2.61 1.23 1.52 1.43 2.46 0 2.36 3.16 3.64
1280*1024 80K/75Hz 0 2.61 1.24 1.52 1.43 2.46 0 2.36 3.16 3.64
DVI 1280*1024 64K 0 3 1.50 1.50 1.50 2.45 0 3.93 3.36 3.36
640*480 31K/60Hz 1.79 1.51 2.48 2.05 1.94 1.69 3.38 0 0.04 3.37
1024*768 60K/75Hz 1.82 1.42 2.29 2.05 1.74 1.69 3.38 0 0.04 3.37
1280*1024 80K/75Hz 1.83 1.41 2.39 2.05 1.75 1.69 3.38 0 0.04 3.37
DVI 1280*1024 64K 2.94 1.05 2.09 1.90 2.51 1.90 3.38 0 0.04 3.37
640*480 31K/60Hz 1.90 0 0 0.11 5.08 3.38 3.38 0.03 3.38 5.12
1024*768 60K/75Hz 1.90 0 0 0.11 5.08 3.38 3.38 0.03 3.38 5.12
1280*1024 80K/75Hz 1.90 0 0 0.11 5.08 3.38 3.38 0.03 3.38 5.12
DVI 1280*1024 64K 1.89 0 0 0.11 5.12 3.38 3.37 0.03 3.38 5.12
640*480 31K/60Hz 5.12 5.12 3.38 0 0 0 0.59 2.47 2.47 2.47
1024*768 60K/75Hz 5.12 5.12 3.38 0 0 0 0.61 2.59 2.59 2.59
1280*1024 80K/75Hz 5.12 5.12 3.38 0 0 0 0.61 2.59 2.59 2.59
DVI1280*1024 64K 5.12 5.12 3.38 0 0 0 0.66 2.54 2.55 2.54
640*480 31K/60Hz 2.47 2.47 0 0 1.34 1.20 3.38 0 2.47 2.47
1024*768 60K/75Hz 2.59 2.59 0 0 1.52 1.05 3.38 0 2.59 2.59
1280*1024 80K/75Hz 2.59 2.59 0 0 1.60 0.95 3.38 0 2.59 2.59
DVI1280*1024 64K 2.47 2.56 0 0 0 0.66 3.38 0 2.55 2.54
IC U4(GM5120)
PIN
MODE 21 22 23 24 25 26 27 28 29 30
IC U4(GM5120)
PIN
MODE 31 32 33 34 35 36 37 38 39 40
IC U4(GM5120)
PIN
MODE 41 42 43 44 45 46 47 48 49 50
IC U4(GM5120)
PIN
MODE 51 52 53 54 55 56 57 58 59 60
IC U4(GM5120)
PIN
MODE 61 62 63 64 65 66 67 68 69 70