Viewsonic E70-9 Service Manual
Service Manual
ViewSonic E70-9
Model No. VCDTS22355-9
17" Digital Controlled Color Monitor
(E70-9_SM_581 - Rev. 1a – July 2002)
ViewSonic
!
381 Brea Canyon Road, Walnut, California 91789 USA - (800) 888-8583
!
Copyright
Copyright
reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language or
computer language, in any form or by any means, electronic, mechanical, magnetic, optical, chemical,
manual or otherwise, without the prior written permission of ViewSonic Corporation.
Disclaimer
ViewSonic makes no representations or warranties, either expressed or implied, with respect to the
contents hereof and specifically disclaims any warranty of merchantability or fitness for any particular
purpose. Further, ViewSonic reserves the right to revise this publication and to make changes from time
to time in the contents hereof without obligation of ViewSonic to notify any person of such revision or
changes.
Trademarks
ViewSonic is a registered trademark of ViewSonic Corporation.
All other trademarks used within this document are the property of their respective owners.
2002 by ViewSonic Corporation. All rights reserved. No part of this publication may be
¤
Revision History
Revision Date Description Of Changes Approval
1a 7/25/02 Initial Release DCN-2430 K.Yang
1b 10/30/02 Revise DCN-2 430 C.Shen
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TABLE OF CONTENTS
SPECIFICATIONS.....................................................................................................1
1.
2.
PRECAUTIONS AND NOTICES...............................................................................3
3.
OPERATING INSTRUCTIONS...............................................................................4
4.
ADJUSTMENT.......................................................................................................... 6
5.
CIRCUIT DESCRIPTION.........................................................................................10
6.
TROUBLE SHOOTING FLOW CHART..................................................................1 3
7.
EXPLODED DIAGRAM AND SPARE PARTS LIST...............................................2 1
8.
SPARE PARTS LIST...............................................................................................2 3
9.
BLOCK DIAGRAM..................................................................................................
10.
PCB LAYOUT DIAGRAM........................................................................................45
11.
SCHEMATIC DIAGRAMS.......................................................................................47
39
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SPECIFICATIONS
1.
1. CRT : 43.2CM(17") 90 Deflection, 29mm Neck, 0.27mm Dot Pitch, Non-Glare Screen
2. Viewable image Size: 40.6CM (16") diagonal
3. Display Color: Unlimited Colors
4. External Controls:
Power On/Off, OSD key, Function knob: Contrast, Brightness, Degauss, H-Size, H-Center, V-Center,
V-Size, ZOOM, Pincushion, Trapezoid, Pin-Balance, Parallelogram, Rotation, Color Temperature, HMoire Reduce, V-Morie, Memory Recall, Language, ViewMeter.
5. Input Video Signal
Mode
Horizontal Freq. (KHz) 31.47 31.47 37.5 43.27 46.87 53.67 60.02 68.67 63.98 35.000 832*624 1024*768
Dot Clock (MHz) 25.18 28.18 31.5 36 49.5 56.25 78.75 94.5 108 30.240 57.283 80.000
Horizontal Lines 720 640 800 1024 1280 640 832 1024
Vertical Lines 400 480 600 768 1024 480 624 768
H. Sync Polarity NEG NEG NEG NEG POS POS POS POS Pos NEG NEG NEG
H. Period (µs) 31.78 31.78 26.67 23.11 21.333 18.63 16.66 14.56 15.63 28.571 20.111 16.600
H. Sync Width (µs) 3.18 3.81 2.03 1.56 1.616 1.138 1.219 1.016 1.037 2.116 1.117 1.200
H. Back Porch (µs) 1.96 1.589 3.81 2.22 3.232 2.702 2.235 2.201 2.296 3.175 3.910 2.200
H. Active (µs) 25.42 25.42 20.32 17.78 16.162 14.22 13 10.83 11.85 21.164 14.524 12.800
Vertical Freq. (Hz) 69.93 59.94 75 85.01 75 85.06 75.02 84.99 60.02 66.667 75.550 74.927
V. Sync Polarity POS NEG NEG NEG POS POS POS POS Pos NEG NEG NEG
V. Period (ms) 14.3 16.68 13.33 11.76 13.333 11.75 13.32 11.76 16.66 15.000 13.414 13.346
V. Sync Width (ms) 0.06 0.06 0.08 0.07 0.064 0.056 0.05 0.044 0.047 0.086 0.060 0.050
V. Back Porch (ms) 1.14 0.79 0.43 0.58 0.448 0.503 0.466 0.524 0.594 1.114 0.784 0.498
V. Active (ms) 12.71 15.25 12.8 11.09 12.8 11.17 12.79 11.18 16 13.714 12.549 12.749
Standard VGA VGA VESA VESA VESA VESA VESA VESA VESA MAC MAC MAC
1 2 3 4 5 6 7 8 9 10 11 12
6. Display Size
Horizontal: 310 mm +/-4mm
Vertical: 230 mm +/-4mm
7. Scanning Frequencies
Horizontal:
Vertical:
8. Factory Preset Timings: 9
User Timings: 8
9. Misconvergence
A Zone: 0.25 mm Max.
B Zone: 0.30 mm Max.
C Zone 0.35 mm Max
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30KHz ~ 72KHz
50 Hz ~ 160 Hz
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10. Video Bandwidth: 120 MHz
11. Power Source:
Switching Mode Power Supply
AC 100 ~240V, 50/60Hz Universal Type
12. Operating Temperature: 0°C to 40°C Ambient
13. Humidity: 5% to 95% Relative, Non-Condensing
14. Weight: 15.5 Kgs(Net), 18.0Kgs(Gross)
15. Package Specifications
Width: 515 mm
Height: 570 mm
Depth: 464mm
16. External Connection:
15 Pin D-sub Connector
AC Power Cord
17. Regulatiory/Safety
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2. PRECAUTIONS AND NOTICES
2-1 SAFETY PRECAUTIONS
1. Observe all caution and safety related notes located inside the display cabinet.
2. Operation of the display with the cover removed, may cause a serious shock hazard from the display
power supply. Work on the display should not be attempted by anyone who is not thoroughly
familiar with precautions necessary when working on high voltage equipment.
3. Do not install, remove or handle the picture tube in any manner unless shatter-proof goggles are
worn. People who are not so equipped should be kept away while handling picture tube. Keep
picture tube away from the body while handling.
4. The picture tube is constructed to limit X-RAY radiation to 0.5 mR/HR. For continued protection,
use the designated replacement tube only, and adjust the voltages so that the designated maximum
rating at the anode will not be exceeded.
5. Symbol “ ” means safety relative parts. The use of substitute replacement parts which do not have
the same characteristics as specified in the parts list may create shock, fire or explode etc.
6. Symbol “Ϫ“ means X-ray relative parts. Before replacing any of these components please read the
parts list in this manual carefully to avoid creating higher anode voltage or x-ray. Especially for
sealed controls, such as VR901, VR902, VR401 and FBT screen VR etc, which were sealed by the
manufacturer once their optimum position has been set, please don’t dismantle them as your likes,
otherwise you will break or damage the component. If you need replace the parts with sealed control,
please adjust the relative VR to make sure the B+ voltage under 61.0V
glue or equivalent, which you can not move away with one screw driver
7. Before returning a serviced display to the customer, a thorough safety test must be performed to
verify that the display is safe to operate without danger or shock. Always perform an AC leakage
current check on the exposed metallic parts of the cabinet, such as screw heads.
Test method for current leakage is described as follow.
(a) Plug the AC line cord directly into rated AC outlet (do not use a line isolation transformer
during this check).
(b) Use an AC voltmeter having 5000 ohms per volt or with more sensitivity in the following
manner: Connect a 1500 ohms 10 Watt resistor, paralleled by a 0.15UF, AC type capacitor
between a known good earth ground (water pipe, conduit, etc.) and the exposed metallic parts
simultaneously. Measure the AC voltage across the combination of 1500 ohms resistor and
0.15UF capacitor.
(c) Reverse the AC plug at the AC outlet and repeat AC voltage measurements for each exposed
metallic part.
(d) Voltage measured must not exceed 0.5 volts RMS. This corresponds to 0.35 milliamp AC. Any
value exceeding this limit constitutes a potential shock hazard and must be corrected
immediately.
DC and well seal it with A+B
2-2 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, X-RAY radiation or other hazards.
2-3 SERVICE NOTES
1. When replacing parts or circuit boards, clamp the lead wires around terminals before soldering.
2. When replacing a high wattage resistor (more than 1/2W of metal oxide film resistor) in circuit
board, keep the resistor about 10mm (1/2 in) away from circuit board.
3. Keep wires away from high voltage or high temperature components.
4. Keep wires in their original position so as to reduce interference.
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2-4 HIGH VOLTAGE WARNING
Operation of monitor outside of cabinet or with back removed may cause a serious shock hazard. Work
on this model should only be performed by those who are thoroughly familiar with precautions necessary
when working on high voltage equipment.
Exercise care when servicing this chassis with power applied. Many B plus and high voltage terminals are
exposed which, if carelessly contacted, can cause serious shock or result in damage to the chassis.
Maintain interconnecting ground lead connections between chassis and picture tube dag when operating
chassis.
Certain HV failures can increase X-ray radiation. Monitor should not be operated with HV levels
exceeding the specified rating for the chassis type. The maximum operating HV specified for the chassis
used in this monitor is
25.0KV ± 1KV
with a line voltage of 120/240 VAC. Higher voltage may also increase possibility of failure in HV supply.
It is important to maintain specified values of all components in the horizontal and high voltage circuits
and anywhere else in the monitor that could cause a rise in high voltage or operating supply voltages. No
changes should be made to the original design of the monitor. Components shown in the shaded areas on
the schematic should be replaced with exact factory replacement parts. The use of unauthorized substitute
parts may create a shock, fire or other hazard.
To determine the presence of high voltage, use accurate, high impedance, HV meter connected between
second anode lead and CRT dag grounding device. When servicing the High Voltage System, remove
static charge from it by connecting a 10K ohm resistor in series with an insulated wire (such as a test
probe) between picture tube dag and 2nd anode lead.(AC line cord disconnected from AC power outlet.)
The picture tube used in this monitor employs integral implosion protection. Replace with tube of the
same type number for continue safety. Do not lift picture tube by the neck. Handle the picture tube only
after discharging the high voltage completely.
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3. OPERATING INSTRUCTIONS
This procedure gives you instructions for installing and using the Color display.
1. Position the display on the desired operation and plug the power cord into a convenient AC outlet.
Three-wire power cord must be shielded and is provided as a safety precaution as it connects the
chassis and cabinet to the electrical conduit ground. If the AC outlet in your location does not have
provisions for the grounded type plug, the installer should attach the proper adapter to ensure a safe
ground potential.
2. Connect the 15-pin color display shielded signal cable to your signal system device and lock both
screws on the connector to ensure firm grounding. The connector information is as follow:
1
6
11 15
5
10
15 - Pin Color Display Signal Cable
PIN NO. DESCRIPTION PIN NO. DESCRIPTION
1. RED 9. 5V From PC
2. GREEN 10. Sync GND
3. BLUE 11. NC
4. GND 12. SDA
5. GND 13. HORIZ. SYNC
6. GND-R 14.
VERT. SYNC (ϠVCLK)
7. GND-G 15. SCL (DDC CLOCK)
8. GND-B
3. Apply power to the display by turning the power switch to the "ON" position and allow about thirty
seconds for display tube warm-up. The Power-On indicator lights when the display is on.
4. With proper signals feed to the display, a pattern or data should appear on the screen, adjust the
brightness and contrast to the most pleasing display.
5. This monitor has power saving function following the VESA DPMS. Be sure to connect the signal
cable to the PC.
6. If your color display requires service, it must be returned with the power cord.
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ADJUSTMENT
4.
4-1 ADJUSTMENT CONDITIONS AND PRECAUTIONS
1. Approximately 30 minutes should be allowed for warm up before proceeding.
2. Adjustments should be undertaken only on those necessary elements since most of them have been
carefully preset at the factory.
4-2 MAIN ADJUSTMENTS
NO. FUNCTION LOCATION DESIGNATION
1. 14V ADJ PCB - MAIN VR901
2. B + ADJ PCB - MAIN VR902
3. SCREEN ADJ FLY BACK TRANS T402 SCREEN VR
4. FOCUS ADJ FLY BACK TRANS T402 FOCUS
VR1&VR2
5. ABL ADJ PCB - MAIN VR701
6. FUNCTION ADJ -MENU PCB - MAIN SW101
-UP
-DOWN
-EXIT PCB - MAIN SW104
4-3 ADJUSTMENT METHOD
1. 14V, B + & HV voltage adjustment:
A. Chroma-2000 Signal generator or PC equivalent set mode 1, VGA 640X480 pattern 1.0 .
B. Connect a DC Volt meter between TP901 and ground, then adjust VR901 to be 14VDC.
C. Connect a DC Volt meter between TP902 and ground, then adjust VR902 to be 62.0 VDC.
PCB - MAIN SW102
PCB - MAIN SW103
2. Factory preset Timings Adjustment:
A. Press MENU Key to show OSD window press Up or Down Key to switch the functional controls.
B. Press the Up Key to select the "ZOOM" function, then press the MENU Key. While do not release
the MENU Key until the OSD window changed to the Factory preset window.
C. The Factory preset window contains the following functional controls. Select one of the control.
Then press the Up/Down Key to adjust its value for the optimum picture.
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CONTRAST H-MOIRE REDUCE
BRIGHTNESS V-MOIRE REDUCE
H-CENTER R-GAIN
H-SIZE
V-CENTER B-GAIN
V-SIZE R-BIAS
ZOOM G-BIAS
PINCUSHION R-BIAS
TRAPEZOID
PIN-BALANCE
PARALLELOGRAM
ROTATION OSD EXIT
V-LINEARITY RETURN
9300
6500
5000
!
V-LINEARITY
V-size Max range limit.
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G-GAIN
COLOR TEMPERATURE
COLOR TEMPERATURE
COLOR TEMPERATURE
H-size Max range limit.
Trapezoid max range limit.
BOTTOM CORNER
OSD-POSITION DEGAUSS
PI!
Operation time record.
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OSD Menu H-position
E70-9
D. To switches the input signal to the other Timing Mode. Please follow step A ~ C to get the optimum
picture.
E. Select the "
" RETURN function and press the MENU Key, then the Factor Preset window
will be returned to the original OSD window.(user's operating condition)
F. The setting data of the CONTRAST, BRIGHTNESS, PIN-BALANCE, PARALLELOGRAM,
ROTATION, COLOR TEMPERATURE are common mode saved in the memory. Don't needed
adjust it individual at every timing Mode and save in the memory.
3. White Balance, Luminance adjustment:
A. Bias (Low Luminance) adjustment:
(a) Set mode 1024*768 Fv: 85Hz full white pattern.
(b) To make the adjustment condition is under the Factory preset window.
Same as step 2-B.
(c) Warm up more than 20 minutes.
(d) Brightness
screen VR to make Y= 4.0+
(e) Brightness set to raster just cutoff, adjust contrast to be 4FL, then adjust G-Bias
set to maximum. Contrast set to min. full white pattern, then adjust FBT
2cd/m²
, B-Bias
, R-Bias , to make the setting value is(50), then adjust the R.G.B Bias
individual to the color temperature x= 283 ± 10, y= 298 ± 10.
B. Gain (High light) adjustment:
(a) Set mode 1024*768 Fv: 85Hz full white pattern.
(b) Brightness set to raster just cutoff and set the contrast to max.
(c) Adjust G-Gain , B-Gain , R-Gain , to make color temperature x=283 ± 10,
y=298 ± 10.
(d) Change to 20% window white pattern then adjust contrast to 150±10cd/m².
C. Recheck item A&B to make sure both of them in spec. Finally select OSD function to the 9300°K
function, then press the MENU Key. To make the setting data saved in the memory.
D. The adjustment of 6500°K white Balance, May follow step A ~ C , with the x=313 ± 10, y=329 ±
10.
E. Thr adjustment of 5000°K white Balance, May follow step A-C, with the x=346± 10, y=359 ± 10
F. Full white luminance:
(a) Set mode1 1024*768 Fv: 85Hz full white pattern.
(b) Image Size : H:300±4mm V:230±4mm.
(c) Brightness set to raster just cut off and set the contrast to max.
(d) Adjust VR701 to the luminance at 105 ± 10cd/m².
4. Focus Adjustment:
A. Set mode 1024×768 Fv: 85Hz with character full page.
B. Adjust brightness to center and contrast to max.
C. Then adjust focus VR1 to a fine vertical line.
D. Adjust focus VR2 to a fine horizontal line.
E. Repeat step C & D.
5. Purity Adjustment
A. Be sure that the display is not being exposed to any external magnetic fields.
B. Ensure that the spacing between the Purity, Convergence, Magnet, (PCM), assembly and the CRT
stem is 29mm. (See below diagram)
C. Produce a complete, red pattern on the display. Adjust the purity magnet rings on the PCM assembly
to obtain a complete field of the color red. This is done by moving the two tabs in such a manner
that they advance in an opposite direction but at the same time to obtain the same angle between the
two tabs, which should be approximately 180'.
D. Check the complete blue and complete green patterns to observe their respective color purity. Make
minor adjustments if needed.
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RELATIVE PLACEMENT OF TYPICAL COMPONENTS
Purity Magnets
6-pole Convergence Magnets
4-pole Convergence Magnets
Deflection Yoke
6. Convergence adjustment
A. Produce a magenta crosshatch on the display.
B. Adjust the focus for the best overall focus on the display.
Also adjust the brightness to the desired condition.
C. Vertical red and blue lines are converged by varying the angle between the two tabs of the 4 pole
magnets on the PCM assembly. (See above diagrams)
D. Horizontal red and blue lines are converged by varying the two tabs together, keeping the angle
between them constant.
E. Produce a white crosshatch pattern on the display.
F. Vertical green and magenta lines are converged by varying the angle between the two tabs of the 6-
pole magnets.
G. Horizontal green and magenta lines are converged by varying the two tabs together, keeping the
angle between them constant.
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5. CURCIT DESCRIPTION
5-1 MICRO CONTROLLER CIRCUIT
MICRO Controller
!
The IC101 contains a 6502 8-bit CPU core, 512 bytes of RAM, 16K bytes of ROM,14 channel 8 bit PWM
D/A converters, 2 channel A/D converters for key detection, one 8 bit pre-loadable base timer, internal
H-sync and V-sync signals processor providing mode detection, watch- dog timer preventing system from
abnormal operation, and an I²C bus interface.
H/V sync signals processor
The functions of the sync processor include polarity detection, H-SYNC & V-SYNC signals counting,
Programmable SYNC signals output, free running signal generator. Pin39/Pin40 are for the H-SYNC and VSYNC input, Pin32/Pin33 will output the same signal as input sync signal without delay, and the polarity are
setting in the positive. When no signal input, the Pin32 will output a 61Hz V-SYNC free run signal. The
Pin33 will output a 41.7KHz H-SYNC free run signal. for the monitor testing use.
On Screen Display Controller
The IC105 is designed for display the built-in characters or fonts onto monitor screen. The display operation
is by transforming data and control information from micro controller to RAM through a serial data
interface.
Pin2 is used to control the internal oscillator frequency by DC voltage input from external low pass filter
(R154, C166, R155) and filter (R175, C167) is used to regulate the appropriate bias current for internal
oscillator the resonate at specific dot frequency.
Pin5 is input the horizontal fly back pulse, for PLL generator tracking.
Pin6 is left floating, I²C bus is enabled. Otherwise the SPI bus is enabled.
Pin7 the external data transfer through this pin to internal display registers and control registers
Pin8 the clock-input pin is used to synchronize the data transfer.
Pin10 is input the vertical flyback pulse for synchronizing the vertical position.
Pin12 is output a blanking signal to cut off external R.G.B signals of VGA while this chip is displaying
characters or windows.
Pin13, Pin14, Pin15 is used to output the OSD (B.G.R) video signal.
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5-2 DEFLECTION CIRCUIT
The deflection circuit is achieved by a high performance and efficient solution IC 401 (TDA9116) for this
monitor. The concept is fully DC controllable and can be used in applications with a micro-controller
solutions.
The TDA9116 provides sync. Processing with full auto sync. Capability, a flexible SMPS block and an
extensive set of geometry control facilities. Further the IC generates the drive waveforms for DC coupled
vertical boosters to the TDA9302H.
Horizontal Oscillator
The oscillator is of the relaxation type and requires a capacitor of 1nF C409 at pin6. The free running
frequency is determined by a resistor R412 5.1K form pin8 to ground.
PLL 1 Phase Detector
The phase detector is a standard one using switched current sources. It compares the middle of H-sync.
with a fixed point on the oscillator saw-tooth voltage. The PLL loop filter C435, C437, R411 is connected
to Pin9.
PLL2 Phase Detector
This phase detector is similar to the PLL1 detector and compares the line flyback pulse at pin 12 with the
oscillator saw-tooth voltage. The PLL2 detector thus compensates for the delay in the external H-deflection
circuit by adjusting the phase of the HDRV output pulses. The phase between H-flyback and H-sync can be
controlled at pin5.
X-ray Protection
The X-ray protection input pin25 provides a voltage detector with a precise threshold. If the voltage
exceeds this threshold for a certain time, an internal latch switches the whole IC into protection mode. In
this mode several pins are forced into defined states:
Pin28 (BDRV) is floating
Pin26 (HDRV) is floating
Pin21, 23 ( VOUT 1, 2) are floating
Vertical Oscillator
The vertical free –running frequency is determined by the resistor C613, C616, R616 at pin22. Usually the
free-running frequency should be lower than the minimum trigger frequency.
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5-3 TRANSISTOR & DIODE CIRCUIT
LOCATION CIRCUIT FUNCTION DESCRIPTION
D901 ~ D904 Bridge Rectifier for AC Source
D910 Clamp Diode for Snubber CKT
D918, D919 Rectifier for Output Voltage
D922 Rectifier for Output Voltage
D923 Rectifier for Output Voltage
D925 Rectifier for B+ Supply
D929 B+ Feed Back Rectifier from F.B.T Pulse
Q901 MOS FET for Switching Power Control.
Q907, Q908 Use for Off-Mode to Cut-off 6.3V Supply Voltage
Q909, Q910 Use for Stand-By or Suspend Mode to Cut-off 14V Supply Voltage
Q912, Q920 Push-Pull Topology to Drive Q911
Q913 Degaussing Switcher Transistor
Q921 5V Regulator Transistor
Q401 Turn-on at Power ON/OFF and Change Mode to Protect Hor.Block
Q402 HOR. Driver Transistor
Q407, Q408 As a Switcher for Horizontal S Correction CKT
Q426 Horizontal s correction control MOSFET
Q404, Q405 As Differential Amp. to Drive Q406
Q406 Transistor for H-Size Control
Q705 Brightness Control CKT
Q741 , Q742 V-Dynamic focus CKT
Q821 ~ Q823,
Q830 ~ Q832
Video DC Restoration control transistor
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6. TROUBLE SHOOTING FLOW CHART
6-1 NO RASTER, CRT RELATIVE CIRCUIT PROBLEMS
CHECK MAIN PCB POWER
CHECK MAIN PCB POWER SUPPLY
SUPPLY 59.5V,14V,78V
53V, 14V, 78V
NG
OK
CHECK THE HIGE VOLTAGE OF
CHECK THE HIGE VOLTAGE
CRT ABOUT 24~25KV
OF CRT ABOUT 24.5 ~ 25.5KV
CHECK POWER SAVING CIRCUIT,
H-SYNC, V-SYNC SIGNAL
Q909, Q910
OK
REFER ITEM S.M.P.S.
OK
CHECK THE VOLTAGE OF CRT
HEATER ABOUT 6.3V
OK
CHECK SCREEN VOLTAGE ABOUT
400V TO 600V
OK
BRIGHTNESS SET TO MAX. THEN
CHECK CRT G1 VOLTAGE
OK
CHECK VOLTAGE OF THE CRT
CATHODE ABOUT 55V TO 65V
NG
NG
LESS THAN 300V
NG
CHECK FAILSAFE CKT IC401
PIN 25 RELATIVE CKT.
CHECK CRT'S HEATER RELATIVE
CIRCUIT Q907, Q908
CHECK FBT
CHECK BRIGHTNESS CIRCUIT
CHECK BRIGHTNESS CIRCUIT
Q705 RELATIVE CKT.
Q703, Q704, Q705 RELATIVE CKT.
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NG
REFER ITEM 6-2
"ABNORMAL DISPLAY"
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