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C

2009

- 5 -

IC Remove/Replacement
Some  chassis  circuit  boards  have  slotted  holes  (oblong)  through
which  the  IC  leads  are  inserted  and  then  bent  flat  against  the
circuit foil. When holes are the slotted type, the following technique
should be used to remove and replace the IC. When working with
boards  using  the  familiar  round  hole,  use  the  standard  technique
as outlined in paragraphs 5 and 6 above.

Removal
1.  Desolder and straighten each IC lead in one operation by gently

prying  up  on  the  lead  with  the  soldering  iron  tip  as  the  solder
melts.

2.  Draw  away  the  melted  solder  with  an  anti-static  suction-type

solder removal device (or with solder braid) before removing the
IC.

Replacement
1.  Carefully insert the replacement IC in the circuit board.
2.  Carefully  bend  each  IC  lead  against  the  circuit  foil  pad  and

solder it.

3.  Clean the soldered areas with a small wire-bristle brush.

(It is not necessary to reapply acrylic coating to the areas).

"Small-Signal" Discrete Transistor
Removal/Replacement
1.  Remove the defective transistor by clipping its leads as close as

possible to the component body.

2.  Bend into a "U" shape the end of each of three leads remaining

on the circuit board.

3.  Bend into a "U" shape the replacement transistor leads.
4.  Connect  the  replacement  transistor  leads  to  the  corresponding

leads  extending  from  the  circuit  board  and  crimp  the  "U"  with
long  nose  pliers  to  insure  metal  to  metal  contact  then  solder
each connection.

Power Output, Transistor Device
Removal/Replacement
1.  Heat and remove all solder from around the transistor leads.
2. Remove the heat sink mounting screw (if so equipped).
3.  Carefully remove the transistor from the heat sink of the circuit

board.

4.  Insert new transistor in the circuit board.
5. Solder each transistor lead, and clip off excess lead.
6.  Replace heat sink.

Diode Removal/Replacement
1.  Remove  defective  diode  by  clipping  its  leads  as  close  as

possible to diode body.

2.  Bend  the  two  remaining  leads  perpendicular  y  to  the  circuit

board.

3.  Observing  diode  polarity,  wrap  each  lead  of  the  new  diode

around the corresponding lead on the circuit board.

4.  Securely crimp each connection and solder it.
5.

Inspect  (on  the  circuit  board  copper  side)  the  solder  joints  of

the two "original" leads. If they are not shiny, reheat them and if
necessary, apply additional solder.

Fuse and Conventional Resistor
Removal/Replacement
1.  Clip each fuse or resistor lead at top of the circuit board hollow

stake.

2.  Securely  crimp  the  leads  of  replacement  component  around

notch at stake top.

3.  Solder the connections.

CAUTION: Maintain  original  spacing  between  the  replaced
component  and  adjacent  components  and  the  circuit  board  to
prevent excessive component temperatures.

Circuit Board Foil Repair
Excessive  heat  applied  to  the  copper  foil  of  any  printed  circuit
board  will  weaken  the  adhesive  that  bonds  the  foil  to  the  circuit
board  causing  the  foil  to  separate  from  or  "lift-off"  the  board.  The
following  guidelines  and  procedures  should  be  followed  whenever
this condition is encountered.

At IC Connections
To  repair  a  defective  copper  pattern  at  IC  connections  use  the
following  procedure  to  install  a  jumper  wire  on  the  copper  pattern
side  of  the  circuit  board.  (Use  this  technique  only  on  IC
connections).

1.  Carefully  remove  the  damaged  copper  pattern  with  a  sharp

knife. (Remove only as much copper as absolutely necessary).

2.  carefully  scratch  away  the  solder  resist  and  acrylic  coating  (if

used) from the end of the remaining copper pattern.

3.  Bend a small "U" in one end of a small gauge jumper wire and

carefully crimp it around the IC pin. Solder the IC connection.

4.  Route  the  jumper  wire  along  the  path  of  the  out-away  copper

pattern and let it overlap the previously scraped end of the good
copper  pattern.  Solder  the  overlapped  area  and  clip  off  any
excess jumper wire.

At Other Connections
Use  the  following  technique  to  repair  the  defective  copper  pattern
at  connections  other  than  IC  Pins.  This  technique  involves  the
installation  of  a  jumper  wire  on  the  component  side  of  the  circuit
board.

1.  Remove the defective copper pattern with a sharp knife.

Remove at least 1/4 inch of copper, to ensure that a hazardous
condition will not exist if the jumper wire opens.

2.  Trace  along  the  copper  pattern  from  both  sides  of  the  pattern

break  and  locate  the  nearest  component  that  is  directly
connected to the affected copper pattern.

3.  Connect  insulated  20-gauge  jumper  wire  from  the  lead  of  the

nearest component on one side of the pattern break to the lead
of the nearest component on the other side.
Carefully crimp and solder the connections.
CAUTION: Be sure the insulated jumper wire is dressed so the
it does not touch components or sharp edges.

C

2009

- 6 -

NOTE : Specifications and others are subject to change without notice for improvement.

4.1 General Specification

This  specification  is  applied  to  the  LCD  TV  used  LA92B
chassis.

Each part is tested as below without special appointment.

1) Temperature :  25±5ºC (77±9ºF), CST : 40±5ºC
2) Relative Humidity :  65±10%
3) Power Voltage : Standard input voltage(100~240V@50/60Hz)

* Standard Voltage of each products is marked by models.

4) Specification  and  performance  of  each  parts  are  followed

each  drawing  and  specification  by  part  number  in
accordance with BOM.

5) The receiver must be operated for about 5 minutes prior to

the adjustment.

1) Performance: LGE TV test method followed 
2) Demanded other specification 

- Safety: UL, CSA, IEC specification, CE
- EMC: FCC, ICES, IEC specification, CE

No

Item 

Specification 

Remark

1

Receiving System

ATSC/ NTSC-M 

2

Aspect Ratio

16:9

3

LCD Module 

LC470WUF-SBM1(Without Inverter)

FHD+Trumotion240Hz 

47LH55-UA

LC550WUD-SBA1(With Inverter)

FHD+120Hz 

55LH40-UA

LC550WUD-SBM1(With Inverter)

FHD+Trumotion240Hz 

55LH55-UA

4

Available Channel

1) VHF : 02 ~ 13

2) UHF : 14 ~ 69

3) DTV : 02 ~ 69

4) CATV : 01 ~135

5) CADTV : 01 ~ 135

5

Operating Environment 

Temp.:0 ~ 40 deg

Humidity : ~ 80 %

6

Storage Environment 

Temp.:-20 ~ 60 deg

Humidity : ~ 85 %

7Input Voltage 

AC100 ~240V,50/60Hz

8

Tuning system

FS

4.2 EyeQ-Green Motion Characters.

Ambient  

Calculative Sensor 

Backlight UI 

Contrast 

Brightness 

Sharpness

Color

Illumination 

Illumination

500 

300 

100 

100 

50 

70

70

300

180 

55

90

50

62

50

200 

120 

25 

90 

50 

58 

54

50 

42 

0 

90 

50 

52 

65

- 7-

C

2009

No Item 

Min 

Typ

Max 

Unit 

Remark

1. Force Stability –Incline Plane Tip Test 

10 

deg 

IEC60065

2. Force Stability –Level Tip Test 

weigthx0.13x9.8

N

3. Isolation Gap,AC-AC 

3 

mm

4. Isolation Gap,AC-DC

3 

mm

5. Isolation Gap,Primary <-> GND

3 

mm

Isolation Gap,Primary <-> Secondary

6.0

mm 

6. Power Consumption,Max 

280W 

47LH55-UA

(1/8W non-clipped 

max.audio signal &Input voltage

360W

55LH40/55-UA

International VideoSignal)

7. Power Consumption,Stand by (Input

0.5 

1W 

(ST-BY power saving circuit)

8. Power Consumption,Switch off 

0.02 W

9. Energy 

Saving Off 

100 

%

<Test Condition>

Minimum 

70 

75 

80 

%

Full white pattern

Medium 

48 

53 

58 

%

Maximum 

22

27 

32 

%

Screen Off 

15 

%

10. OPC Black luminance

54 

60 

66 

%

150 Gray Input

<Test Condition>

difference of OPC

-white No Luminance

Vivid mode,4% window white pattern

on/off mode

difference

*255 Gray Input Case:white/black

No Luminance difference

11. Dielectric Voltage

GND 

1500 V/min at 100mA 

1.5KV

IEC60065

SIGNAL 

3000 V/min at 100mA 

3KV

12. Isolation Resistance 

4

∞

MΩ

13. Leakage Current 

0.35 

mA rms

14. UL Compliance 

Safety 

UL1492 

EMC 

FCC Class B

15.  CSA Compliance 

Safety 

CSA C22.2.

EMC 

IC Class B

No 

Item 

Standard 

Unit

Remark

1.

VSB Receiving 

CH.2 ~69CH

1 ~135CH(CATV)

1 ~135CH(CADTV))

2.

Video Resolution 

ATSC 18 FORMAT

3.

Audio Bit Resolution

32,40,48,56,64,80,96,112,128,160,

Kbps

192,224,256,320,384,448,512,576,640

4.

VSB RF Input

75Ω unbalanced, F type Connector input

5.

Sync Stable Time 

Under 3.0 

<None>SEC

- 8 -

C

2009

7.1 Module optical specification

7.2Max Luminance &Contrast measure standard specification

- Max Luminance measure specification
1) In non-impressed condition, measure peak brightness displayable as much as possible LCD module.
2) Measuring instrument: CA-210 or a sort of Color Analyzer.
3) Pattern Generator :VG- 828 or a sort of digital pattern generator (displayable Full White &1/25 White Window pattern)
4) Measure condition
• Test pattern: in center,1/5(H)*1/5(V) of Window Pattern (white pattern in non-impressed condition)
• SET condition: Contrast &Brightness Level 100%
• Environment condition : Dark room in the non outside light
• Video menu option condition

5) Measurement 
• Do heat-run LCD module at 30minutes in normal temperature (25°C)by using full white pattern of 15%signal level(38 gray level).
• Impress test pattern signal in 1/5(H)*1/5(V)White Window of 100%(255Gray Level)
• measure 3 times brightness of central white window,and mark peak brightness in max brightness degree
• measure the same condition in video signal /RGB signal.

- Luminance uniformity measure specification
1) Impress 100%(255Gray Level) full white pattern at the same peak brightness measurement.
2) Measure average brightness in 5 points.

Signal 

Picture Mode

Dynamic Contrast 

Dynamic Color

Black Level

OPC

RF

NTSC-M

Vivid

High 

High 

Low

Off

AV 

NTSC-J 

Vivid 

High 

High 

High

Off

Component 

720P

Vivid 

High 

High 

High

Off

RGB 

1024x768

Vivid 

High

NA 

NA

Off

HDMI 

DTV 720P 

Vivid 

High 

High 

Low

Off

No.

Item 

Specification 

Min.

Typ.

Max.

Remark

1.

Max Luminance

Modele 

400

500

cd/m2

(Center1-point/ Ful white pattern)

2.

Luminance uniformity

Luminance 

77

3.  Contrast Ratio

1000: 1

1400: 1

55LH40/55-UA

40000: 1(DCR) 50000:1(DCR)

WX

Typ 

0.279

Typ 

55LH40-UA

White

WY

-0.03

0.292

+0.03

4.

Color Coordinates

Xr

0.637

RED

Yr

0.333

Xg 

0.287

Green

Yg 

0.605

Xb 

0.145

Blue

Yb

0.064

5.  Color Temperatue

Cool

Typ

0.276 

Typ

85% Full white pattern

-0.015

0.283 

+0.015

**The W/B Tolerance is

Medium

0.285 

± 0.015 for Adjustment

0.293 

Dynamic contrast :off

Warm

0.313

Dynamic color :off

0.329

Energy saving mode :off

6.

Color Distortion, DG

10.0 

%

7.

Color Distortion,DP 

10.0 

deg

8.

Color S/N,AM/FM 

43.0 

dB

9.

Color Killer Sensitivity

-80 

dB