Product Service Manual - Level 2
Product Service Manual - Level 2
Product Service Manual - Level 2
Version: 001
Date:07/06/12
Notice:
- For RO to input specific “Legal Requirement” in specific NS regarding to responsibility
and liability statements.
- Please check BenQ’s eSupport web site, http://esupport.benq.com, to ensure that you
have the most recent version of this manual.
First Edition (June, 2006)
© Copyright BenQ Corporation 2006. All Right Reserved.
Content Index
Content Index
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:
z This monitor should be operated only at the correct power sources indicated on the label on the rear of the
monitor. If you’re unsure of the power supply in you residence, consult your local dealer or Power
Company.
z Do 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.
z Do not remove the monitor cabinet. There is high-voltage parts inside that may cause electric shock to
human bodies.
z Stop using the monitor if the cabinet is damaged. Have it checked by a service technician.
z Put your monitor only in a lean, cool, dry environment. If it gets wet, unplug the power cable immediately
and consult your closed dealer.
z Always 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.
z Do not place heavy objects on the monitor or power cord.
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.
z When replacing parts or circuit boards, clamp the lead wires around terminals before soldering.
z Keep wires away from high voltage, high temperature components and sharp edges.
2. Product Overview
2.1 Power supply
Item condition Spec OK NA Remark
240Vac,cold 60A(max)
star,25°C
Earth Leakage Current
Hi-pot
V1R2
Preset Pixel Format Horz Freq(kHz) Horz Polarity Vert Freq (Hz) Vert Polarity Pixel Clk (MHz)
Preset Pixel Format Horz Freq(kHz) Horz Polarity Vert Freq (Hz) Vert Polarity Pixel Clk (MHz)
table (under
1280x1024).
CR>10 160 √
disable
2.7.4 Environment
Item condition Spec OK NA Remark
2.7.5 Transportation
Item condition Spec OK NA Remark
2.7.7 Reliability
Excluding the
MTBF ≧ 50,000 Hours
LCD, CCFL
Note. Display an all WHITE field at mid Brightness and Contrast settings
Items Specification
Speaker NA
Input impedance NA
Frequency response range NA
Signal to noise ratio NA
Output power NA
10
2.10.2 Weight
Item condition Spec OK NA
Monitor (Net) 3.7±0.3 Kg ( Net ) √
Monitor with packing(Gross) 4.7±0.3Kg( Gross / with
√
packing )
2.10.3 Plastic
Item condition Spec OK NA Remark
Flammability 94-HB √
Heat deflection to ABS 80°C √
UV stability ABS Delta E<12 √
resin ABS √
11
12
Without Pallet
40’ N/A N/A N/A
LxWxH LxWxH
429x416x110mm 440x434x120mm
13
14
PANEL *1
HRN LVDS FFC *1
FOIL,AI,DOUBLE,COND,60x35xT0.07mm,LE2
016*1
BEZEL *1
PCBA KEY PAD*1
ASSY BEZEL *1 FUNCTION BUTTON *1
KEY PAD CABLE *1
SCREW,P,CROSS POWER BUTTON *1
LENS *1
ASSY,BACK COVER *1
BACK COVER *!
SCREW,P,CROSS,M4*8,BLACK,
LOGO BACK *1
NL(NYLOK)*2
STAND FRONT *1
STAND BACK *1
SCREW,B,CROSS,T.T-4*10,BLK ,R
OHS *2
BASE *1 LE 1785
RUBBER *5
LCD Monitor
ASSY BASE *1
15
Assemble
the panel
1
with
front-bezel
Assemble
chassis &
2
Plug in the
LVDS
Keypad
3
assembly
Plug in the
4
lamp lines
Back cover
5
assembly
16
Assemble the
6
stand
7 Lock screw
Base
10
assembly
17
LE 1785
LCD Monitor
BASE, LE1785*1
Rubber Foot , *5 ASSY BASE
STAND FRONT *1
ASSY STAND
STAND BACK *1
HINGE *1
BEZEL *1
ASSY FRONT BEZEL
PCBA KEY PAD*1
SCREW,P,CROSS W/WAS,M3*6,Zn FUNCTION BUTTON *1
KEY PAD CABLE *1
ROHS*1 POWER BUTTON *1
PANEL *1
HRN LVDS FFC *1
FOIL,AI,DOUBLE,COND,60x35xT0.07
mm,LE2016*1
HRN ASS'Y *1
SCREW,P,CROSS W/WAS,M3*6,Zn
ROHS*5
BOLT,#4-40x11.8,Ni ROHS *4
Note:
18
Disassemble
the base(press
1
two points as
photo showing)
Disassemble
2 the stand(take
out screw)
Disassemble
4
back cover
Move out
5
LVDS
19
Take out
screw and
6
disassemble
keypad
Disassemble
7
the LVDS
Take apart
8 the chassis
aside
LCD Monitor
D-Sub
ISP Board
D-SUB
Insert to Parallel
Parallel
Port on PC
Port
2. Press the “connect” button in ISP.exe, and select the device type, which is used in this monitor. Choose the
20
21
The On-Screen Display (OSD) shall be an easy to use icon based menu through keypad OSD buttons or
remote control unit. The unit shall leave the factory with all OSD controls set to their default values
Level 1 Level 2 Level 3 Level 4 Default
Auto Adjustment - - -
H. Position (0~100) - 50
Phase (0~63) - -
Brightness (0~100) - 90
Contrast (0~100) - 50
Sharpness (1~5) - 3
Normal Normal
Bluish -
PICTURE Reddish -
*Color temperature
Color User Mode 100
¾ Red (0~100)
¾ Green (0~100)
¾ Blue (0~100)
Reset Color (YES/NO)
Standard Standard
1.任一项模式下
Movie Sharpness 不可调节
Senseye Demo 设为
22
4.2.3.4 After repair, to ensure the quality you should do the following test and adjustment
23
cannot be distinguished.
Temperature shades
Chroma Signal Generator
2. Measure color temperature, check it complies with the and color analyzer
following temperature :
VGA cable When VGA cable is not plugged, the monitor will work in power saving
Visual check
detector mode.
Chroma Signal Generator
1. Mode:1280×1024@60Hz
of the picture.
4. Contrast: Default
State Power Consumption LED color
Normal green
Stand By amber
24
1
R803 10 3 +14V
2
D801 510K
2
C803 R828
BL4-06 D803 SRF8-10 470uF/25V 9.1V
100R 1W
+ 1
4n7/1KV
1
C808 C810 ZD801
R801 R807 2 R806 C811 1000uF 25V R829 2
1
1
3M3 510K 10R 1n 500V 200R
2
2
2 3 3
2
1 2 2 1 Q802
9 2SC1815
L803 B801
D804 8 1 5uH 5A BEAD CORE 3.5x9 1
1
-
R805 MUR1100 2
VCC5V
1
2
3M3 3 3
4
2
12mH C812 C809 10K 5.6V 16V
2 3 R824 D806 C814 C822
1
1000u 10V
1
3M3
6
1 4 5
C815
1
2
ZD806
2
1
R811 R810
2
LTV817 5K1 1%
NC ZD8054 1
1
R815
2
1 2 1 2
6
1
R820 R821 6.8R 1K
L
1
D
2
1K
TOP246Y C C816
2
1
4
D809 R
C801 C806 C818 1N4148W A IC803 R819
1
2
2200P Y2 2200P Y 2 C813 R817 C817 47u/25V TL431 10K
2
2
2
1
250V 250V 47p 1KV 12K 0.1u 50V R818
C819
1
3K3 1%
RT801 47u/25V
5R C824
PGND 4700P Y 1
F801
2A 250V
CN801
1 InnoLux BENQ(G700)
2 VCC5V
3 Document Number : SIZE : APPRO BY :
L
4
N
1 2 3 ON/OFF
5
BRIGHTNESS
new A4
6
P801 7 TITLE :
8 CHECK BY :
AC IN POWER SUPPLY
TO SCALER BD CN101 C821
0.1u/50V
DATE : 2007-04-07 DRAWN BY :
Rev :
SHEET 2 OF 3 04
25
IF Board
26
27
28
the soft-start, the high voltage current source is turned off and the CONTROL pin will start discharging in
response to the supply current drawn by the control circuitry.
Resistor R803, R807, R824 and R825 are for line over voltage shut-down (OVP) and line under-voltage
detection (UVP).Resistors R801, R805, R822, and R823 are for external current limit adjustment, and
used to reduce the current limit externally to a value close to the operating peak current of primary about
1.35A. The mean is power will protected when the primary current over about 1.35A.
When PWM is turned off, the main current flow will be consumed through D804 and ZD802, This will
prevent MOSFET which built-in IC802 from being damaged under large current impulse and voltage
spike.
D806 and C815 provide internal Auxiliary current to CONTROL pin during normal operation. In addition,
error amplifier and feedback current to the CONTROL pin are for duty cycle control.
For 5VDC output OVP, ZD803 is a zener diode, when 5V output voltage becomes up to 5.6V, the zener
current cause R819 voltage become up to 0.7V, Q801 is triggered and OVP starts. For 12VDC output
OVP, ZD804 is a Zener Diode, when 12V output voltage becomes up to 15V, the zener current cause
R819 voltage become up to 0.7V, Q801 is triggered and OVP starts. The collector current of Q801 is
used to make build-in diode light. FB Current of IC802 will be changed; it can change the voltage from
T801.
Q802, R827, R828 and ZD801 make up of dummy loading circuit. For start-up sequence, during 5V
output take place high loading first, this dummy loading circuit operated to insure 12V not be increased.
Low voltage to high voltage circuit
14VDC provides the power for IC501; the control signals Brightness and ON/OFF come from I/F board.
ON/OFF signal connect to pin10 of IC501 and makes IC501 enable. Brightness signal connect to pin4 of IC501
and regulates the panel brightness, R501, R518, C518 make up a network of delaying time circuit and R512,
R514 make up a divided voltage network, C510 is used to dump noise. The operation frequency is determined
by the external Resistor R508 and capacitor C512 connected to pin13 of IC501. BURST MODE regulated
29
dimming frequency is determined by the external resistor R507 and capacitor C516 connected to pin11 of
IC501. C511 is used for soft start and compensation, C507, C518 are used for dump noise.
The output drives, include DRV1, DRV2 (pins1,15 respectively) output square pulses to drive
MOSFET U501, U502, and each of U501, U502 , is consist of a N channel MOSFET. U501,OR U502
work as Push-Pull- topology, it is high efficient, PWM switching.
During start up, VSEN (pin6) senses the voltage at the transformer secondary. When VSEN reaches 3.0V,
the output voltage is regulated. If no current is sensed approximately 2seconds IC501 shut off.
The current flowing through CCFL is sensed and regulated through sense resistor R509, R534. The feedback
voltage connected to Pin5 (ISEN), then compared with a reference voltage (1.5V) via a current amplifier,
resulting in PWM drive outputs to PUSH-PULL switches
12V
PWM
PHOTO-COUPLER SIGNAL
COMTROL
ISOLATION COLLENTION
CIRCUIT
PRIMARY SECONDARY
30
Vcc+14v
Lamp1
+5v
PWM CONTROL 50KHz
PWM1 Switch(MOSFET) Transformer
(OZ9938GN) Lamp2
1 50KHz
PWM2
Brightnes
s
ON/OFF
50KHz
Lamp4
Open protection Lamp1
Lamp2
Lamp3
Lamp3
PUSH-PULL INVERTER
5.3.1 I/F Circuit
31
into U103#24.
- U108 power is supplied by PC via CN103#9, or supplied by Monitor self via D103.
- U108 is an EEPROM IC which is memory and EDID data saved in it.
- U106 (RTD2525LH ) #29. #30. #31~#38 output 8 bit even LVDS digital data to panel control circuit
through CN104.
- U106 (RTD2525LH) #21~#30 output 8 bit odd LVDS digital data to panel control circuit through
CN104.
- U103 (RTD2120_LQFP48 ) #44 outputs Brightness “PWM” signals to control CCFL brightness.
- U103 (RTD2120_LQFP48 ) #39 output PANELPOWER ON/OFF to make Q112 conducted, and
then make Q110 conducted, +5V flow to CN105#1~#3 as Panel VDD .
- U103 (RTD2120_LQFP48 ) #46 output CCFL_ON/OFF ”H” and “L” potential to control Inverter
on/off.
Please refer to RTD2120_LQFP48 Pin Assignments table in IC spec.
32
No raster?
Yes
LED Blue?
Yes
Backlight can’t
be turned on.
Yes
No
Is there 5Vdc Check power supply
voltage on pin2
Yes
Yes No
R501 open
Yes
Yes
No T501, T502 fail
Is ok T501, T502?
Yes
END
Check feedback circuit
33
No power
Check pin3 of
Check R801, R805,
IC802 voltage
R822, R823, R817
about 1V
END
34
Check Vpin1-2 of
IC801 about 1V
Check R809,
R814
END
35
Unstable power
Change D806,
C815
END
36
Black Screen
Black Screen
NG
Check VCC Power Fail
OK
Check VCC3.3V NG
Check U102
and VCC1.8V
OK
NG
Check Reset Check
Waveform
OK
OK
OK OK
Check CCFL Check
Inverter fail
Enable pin10 of
NG NG
Check R102,R101,R104,
U103 fail and Q101
37
White Screen
White Screen
OK
LVDS cable Workmanship
reinsert
NG
OK
Change LVDS cable NG
LVDS
NG
OK
Check OK
Check Panel Fail
VLCD VLCD
NG
Check panel
Enable of Panel
OK
END
38
Bad Screen
Bad Screen
OK
LVDS cables
Workmanship
reinsert
NG
Change LVDS
cable
NG
NG
Check crystal:
Check X1, C117
pin 15 and
and C118
pin16
OK
Check U106
39
40
41