LG 27BK4 series User manual

Internal Use Only
CHASSIS : LM 8AA
MODEL :27BK4 SERIES
CAUTION
BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
SERVICE MANUAL
LED MONITOR
SERVICE MANUAL
P/NO : MFL69406845(1806-REV01)

Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the
Schematic Diagram and Exploded View.
It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent
Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
General Guidance
An isolation Transformer should always be used during the
servicing of a receiver whose chassis is not isolated from the AC
power line. Use a transformer of adequate power rating as this
protects the technician from accidents resulting in personal injury
from electrical shocks.
It will also protect the receiver and it's components from being
damaged by accidental shorts of the circuitry that may be
inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this TV receiver is blown,
replace it with the specified.
When replacing a high wattage resistor (Oxide Metal Film Resistor,
over 1 W), keep the resistor 10 mm away from PCB.
Keep wires away from high voltage or high temperature parts.
Before returning the receiver to the customer,
always perform an AC leakage current check on the exposed
metallic parts of the cabinet, such as antennas, terminals, etc., to
be sure the set is safe to operate without damage of electrical
shock.
Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug removed from AC source, connect an
electrical jumper across the two AC plug prongs. Place the AC
switch in the on position, connect one lead of ohm-meter to the AC
plug prongs tied together and touch other ohm-meter lead in turn to
each exposed metallic parts such as antenna terminals, phone
jacks, etc.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1 Mȍand 5.2 Mȍ.
When the exposed metal has no return path to the chassis the
reading must be infinite.
An other abnormality exists that must be corrected before the
receiver is returned to the customer.
Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check.
Connect 1.5 K / 10 watt resistor in parallel with a 0.15 uF capacitor
between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
Measure the AC voltage across the resistor using AC voltmeter
with 1000 ohms/volt or more sensitivity.
Reverse plug the AC cord into the AC outlet and repeat AC voltage
measurements for each exposed metallic part. Any voltage
measured must not exceed 0.75 volt RMS which is corresponds to
0.5 mA.
In case any measurement is out of the limits specified, there is
possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
Leakage Current Hot Check circuit
IMPORTANT SAFETY NOTICE
To Instrument's
exposed
METALLIC PARTS
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
AC Volt-meter
SAFETY PRECAUTIONS

SPECIFICATION
No
Item
Content
Measurement
Result
Remark
1
Customer
BRAND
Checked
OK
2
User Model Name
20MK400/22MK430(22BK430)/24MK430(
24BK430)/27MK400(27BK400)
22MK400(22BK400)/24MK400(24BK400)
/27MK430
Checked
OK
3
Sale region
Worldwide
Checked
OK
4
Feature
20MK400
19.5”Wide LCD MNT
Checked
OK
22MK430(
22BK430)
22MK400(
22BK400)
21.5” Wide LCD MNT
Checked
OK
24MK430(
24BK430)
24MK400(
24BK400)
23.8” Wide LCD MNT
23.6”Wide LCD MNT
Checked
OK
27MK400(
27BK400)
27MK430
27” Wide LCD MNT
Checked
OK
5
Chassis Name
LM8AA
Checked
OK
LM8IA(20MK400A)
Checked
OK

6
General
Scope
External SW
& Adj.
5-way joystick switch
Checked
OK
Function
OSD,DDC2B,DDC2AB, HDCP, Control
Lock, Wide/Original, Smart Energy
Saving, Color Weakness, Black level,
Reader mode, Flicker safe
Checked
OK
7
Cable
HDMI
Length : 1.5m±0.05m / Shape :
Detachable Type / Color : Black / Weight :
0.091kg±10%
Checked
OK
SET accessory
P/N : EAD00926125
20MK400A is not suppoted
CABLE : 100Ω±10Ω
CONNECTOR : 100Ω±15Ω
D-sub
Length : 1.5m±0.05m
Shape : Detachable Type / Color : Black /
Weight : 0.095kg±10%
Checked
OK
20MK400A support
CABLE : 75Ω±5Ω
CONNECTOR : 50Ω±5Ω
Checked
OK
8
Power
24MK430(24BK430)/27MK400(27BK400)
/24MK400H(24BK400H)/27MK430H(27B
K430)
Output: DC 19V 1.3A, 24W Adapter
Color: Black, Weight : 154g ±10%,
without vinyl bag
22MK430/22BK430
Output: DC 19V 1.3A, 24W Adapter
Checked
OK
P/N : Refer to Suffix standard

Color:
Black
,
Weight :
154g
±10%,
without vinyl bag
O
r
Output: DC 19V
0.84
A,
16
W Adapter
Color:
Black
,
Weight : 126g ±
10%,
without vinyl bag
2
0MK400/22MK400H(22BK400)
Output: DC 19V
0.84
A,
16
W Adapter
Color:
Black
,
Weight : 126g ±10%,
without vinyl bag
9
Applying
module list
20MK43
0
H***
VMVN
20MK400A***
AUO HD TN
EAJ64447601 / M
195XTN01.0
22MK430(22BK430)
H***MJVN
LGD cDMS
EAT62113804/ LGM215DA41
EAT63400002 / MV215FHB
-
N30
C
ell: EAJ63849701/ LM215WF3
SLS
1
22MK430(22BK430)
H***DJVN
Checked
OK
Refer to Suffix standard

BOE cDMS
EAT63400002 / MV215FHB-N30
Cell: EAJ63869201 *S*EAJ6386920
2 / MV215FHB-N30
22MK430(22BK430)H***EJVN
BOE cDMS
EAT63400003/ MV215FHB-N31
Cell: EAJ64410301 MV215FHB-N31
BLU : EBV60978086
22MK430(22BK430)H***KMVN
LGD Normal
EAJ63849701 LM215WF3-SLS1
22MK400H(22BK400)***FJVN
BOE BMS
EAT63474602 / LGM215AB02
Cell : EAJ63989701 HM215WU3-501
BLU : EBV60978050
24MK430(24BK430)H***MJVN
LGD cDMS

EAT62633902 / LGM238LC4-SLA4
Cell:EAJ63109401 /LM238WF1SJK1
BLU : EBV61158019
24MK430(24BK430)H***KMVN
LGD Normal
EAJ63909101 LM238WF1-SLK1
24MK400H(24BK400H)***PJVN
BOE BMS
EAT63415901 / LGM236AB12
Cell : EAJ62549701 HM236WU3-101
BLU : EBV60978047
27MK400(27BK400)H***VMVN
AUO FHD TN SNB
EAJ64447601 / M270HTN025
27MK430H***FEVN
BOE BMS
EAT62953221 / LGM270BC4
Cell : EAJ64670501 MV270FHB-N20
BLU : EBV61138218

27BK430H***DNVN
BOE Module
EAJ63948301
MV270FHM-N20
24MK430H*DJVN
BOE cDMS
EAT62953226/ LGM238BC4
Cell : EAJ64771101 *S*EAJ6477110
2 MV238FHB-N30
BLU : EBV61158027

2. Signal Timing (Resolution)
2.1. Signal (Video & Sync)
 G
+97LPLQJ A
B
C
DEF
Video
Sync
Mode section polarity
DOT
CLOCK[
MHz]
Frequency
[kHz]/[Hz]
Total
Period(E)
Display
(A)
Front
Porch(D)
Sync.
(C)
Back
Porch(B) Measurement Result
Resolution
1
H(Pixels) -
28.321
31.468 900 720 18 108 54 Checked OK
720 X 400
V(Lines) + 70.08 449 400 12 2 35 Checked OK
2
H(Pixels) -
25.175
31.469 800 640 16 96 48 Checked OK
640 x 480
V(Lines) - 59.94 525 480 10 2 33 Checked OK
3
H(Pixels) -
31.5
37.5 840 640 16 64 120 Checked OK
640 x 480
V(Lines) - 75 500 480 1 3 16 Checked OK
4
H(Pixels) +
40.0
37.879 1056 800 40 128 88 Checked OK
800 x 600
V(Lines) + 60.317 628 600 1 4 23 Checked OK
5
H(Pixels) +
49.5
46.875 1056 800 16 80 160 Checked OK
800 x 600
V(Lines) + 75.0 625 600 1 3 21 Checked OK
6
H(Pixels) -
65.0
48.363 1344 1024 24 136 160 Checked OK
1024 x 768
V(Lines) - 60.0 806 768 3 6 29 Checked OK
7
H(Pixels) +
78.75
60.023 1312 1024 16 96 176 Checked OK
1024 x 768
V(Lines) + 75.029 800 768 1 3 28 Checked OK
8
H(Pixels) +
108.0
67.500 1600 1152 64 128 256 Checked OK
1152 x 864
V(Lines) + 75.000 900 864 1 3 32 Checked OK
1) Main Recommended Timing

 G
9
H(Pixels)
+
108.0
63.981
1688
1280
48
112
248
Checked
OK
1280 x 1024
V(Lines)
+
60.023
1066
1024
1
3
38
Checked
OK
10
H(Pixels)
+
135.0
79.976
1688
1280
16
144
248
Checked
OK
1280 x 1024
V(Lines)
+
75.035
1066
1024
1
3
38
Checked
OK
11
H(Pixels)
-
146.25
65.290
2240
1680
104
176
280
Checked
OK
1680 x 1050
V(Lines)
+
59.954
1089
1050
3
6
30
Checked
OK
12
H(Pixels)
+
148.50
67.50
2200
1920
88
44
148
Checked
OK
1920 x 1080
V(Lines)
+
60
1125
1080
4
5
36
Checked
OK
< HDMI>
1) Main Recommended Timing
Mode
section
polarity
DOT
CLOCK[
MHz]
Frequency
[kHz]/[Hz]
Total
Period(E)
Display
(A)
Front
Porch(D)
Sync.
(C)
Back
Porch(B)
Measurement
Result
Resolution
1
H(Pixels)
-
28.321
31.468
900
720
18
108
54
Checked
OK
720 X 400
V(Lines)
+
70.08
449
400
12
2
35
Checked
OK
2
H(Pixels)
-
25.175
31.469
800
640
16
96
48
Checked
OK
640 x 480
V(Lines)
-
59.94
525
480
10
2
33
Checked
OK
3
H(Pixels)
-
31.5
37.5
840
640
16
64
120
Checked
OK
640 x 480
V(Lines)
-
75
500
480
1
3
16
Checked
OK

4
H(Pixels)
+
40.0
37.879
1056
800
40
128
88
Checked
OK
800 x 600
V(Lines)
+
60.317
628
600
1
4
23
Checked
OK
5
H(Pixels)
+
49.5
46.875
1056
800
16
80
160
Checked
OK
800 x 600
V(Lines)
+
75.0
625
600
1
3
21
Checked
OK
6
H(Pixels)
-
65.0
48.363
1344
1024
24
136
160
Checked
OK
1024 x 768
V(Lines)
-
60.0
806
768
3
6
29
Checked
OK
7
H(Pixels)
+
78.75
60.023
1312
1024
16
96
176
Checked
OK
1024 x 768
V(Lines)
+
75.029
800
768
1
3
28
Checked
OK
8
H(Pixels)
+
108.0
67.500
1600
1152
64
128
256
Checked
OK
1152 x 864
V(Lines)
+
75.000
900
864
1
3
32
Checked
OK
9
H(Pixels)
+
108.0
63.981
1688
1280
48
112
248
Checked
OK
1280 x 1024
V(Lines)
+
60.023
1066
1024
1
3
38
Checked
OK
10
H(Pixels)
+
135.0
79.976
1688
1280
16
144
248
Checked
OK
1280 x 1024
V(Lines)
+
75.035
1066
1024
1
3
38
Checked
OK
11
H(Pixels)
-
146.25
65.290
2240
1680
104
176
280
Checked
OK
1680 x 1050
V(Lines)
+
59.954
1089
1050
3
6
30
Checked
OK
12
H(Pixels)
+
148.50
67.50
2200
1920
88
44
148
Checked
OK
1920 x 1080
V(Lines)
+
60
1125
1080
4
5
36
Checked
OK

13
H(Pixels)
+
174.5
83.99
2080
1920
48
32
80
Checked
OK
1920 x 1080
V(Lines)
+
74.97
1119
1080
3
5
31
Checked
OK
6.1.2 HDMI Video input
Factory support
mode
(Preset Mode)
Horizontal
frequency
(KHz)
Vertical
frequency
(Hz)
HDMI
1
480P
31.5
60
O
2
576P
31.25
50
O
3
720P
37.5
50
O
4
720P
45
60
O
5
1080P
56.25
50
O
6
1080P
67.5
60
O
(Recommend Mode)

1. Monitor JIGs
Novatek JIG(P/N RAD32227901) LG Monitor JIG(P/N RAD33028001)
1. How to connect
1.1 Connect the PC USB cable and HDMI (or D-sub) Cable as like below picture
Monitor
PC

1.2 USB cable is connected with PC(or Desktop PC)
HDMI(or D-Sub) cable is connected on Monitor.
** If there is only DVI port on Monitor, you can use HDMI to DVI cable instead of HDMI cable
Connect
to PC
Set(Monitor)
Connect to Monitor
Connect to PC
1. Kinds of ISP Program
1.1 Install program “EasyWriter_20160505.exe” with below sequence
- Right click of Install program then install with as administrator.
- Reboot PC
- Open NVT EasyWriter program then connect zig and USB cable
Novatek
Suffix “V”
Novatek JIG
(P/N RAD32227901)

2. Novatek
2.1 execute EasyWriter Tool and then select [Setup ISP Tool ] on [Option]
2.2 change the setting as like below image and then click [Confirm Change] button
Select ISP Jig type depends on board
Novatek (P/N RAD32227901)LG Monitor JIG(P/N RAD33028001)
Select FTDI Mode. Select NvtEasyUSBMode
Monitor
Monitor
PC
PC

2.3 After start EasyWriter Tool, like below image, on [Option] tab,
lick the [WP Pin Select]
2.4 Check the WP pin slection.For the rest, it must be unchecked. And then click
the [save].

2.5 Setting of the FE2P Block Select
Check the bank0, bank1, bank2, bank3
2.6 After start EasyWriter Tool, like below image, on [Option] tab,
check [FE2P Mode Enable]
2.7 click [ Load file ] icon, and select the download file.( *.hex or *.bin)
•Caution : If not checked FE2P Mode Enable, EDID and HDCP key will be deleted.

2.8 click [ Auto] icon for download new File on Monitor.
2.9 check the [ end ] message, that means completed download.

BLOCK DIAGRAM
LVDS
SCALER
NT68771V
Panel(1920x1080)
FLASH
8M
SPI
Control Key
Key1 & Key2
TJ5631
LDO
3.3V
1.2V
MP2331
DC/DC
5V
Headphone
OUT
HDMI
RGB
5V

EXPLODED VIEW
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts
are identified by in the Schematic Diagram and EXPLODED VIEW.
It is essential that these special safety parts should be replaced with the same components as recommended
in this manual to prevent Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
IMPORTANT SAFETY NOTICE
540
or
330
900
910
200 400
510
300
500