manualshive.com logo in svg

LG L1750U-BN, Service Manual

Share
Download
LG L1750U-BN Service Manual Download Page 11

- 8 -

DISASSEMBLY

Remove the screws.

Disassemble cover.

# 1

Remove line.

# 2

# 3

# 4

# 5

# 6

Remove  Al-tape from control pcb fix.

Remove the 4 screws from each side of metal

frame.

1. Pull the front cover  upward.

2. Then, let the all latches are separated.

3. Put the  front face  down.

# 7

# 8

Disassembly Tilt swivl.

Pell off  the line.

Summary of Contents for L1750U-BN

Page 1: ...28 Including blank 1page Part No 1 2 Service Guide Specification Service Guide Specification Changes 4 REV NO MM DD YY SIGNATURE CHANGE NO CHANGE CONTENTS 1 2 3 4 5 7 6 SUFFIX L1750U SNN L1750U BNN L1750U GNN LG 38289S0012A 1 Origin Notification LGEDI Printed in Indonesia LGEWA Printed in U K LGESP Printed in Brazil LGEMX Printed in Mexico LGENT Printed in China LGEIL Printed in India 8 Special In...

Page 2: ...t Pagination sheet P NO 38289S0012A Total pages 28pages Cover English 2 English 3 English 4 English English Rear Cover Front cover Inside blank English English 22 English 23 English 24 English 25 Rear cover Inside 26 ...

Page 3: ...l http www LGEservice com techsup html CAUTION BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL CHASSIS NO CL 94 MODEL L1750U SN L1750U SNN AN QP L1750U BN L1750U BNN AN QP L1750U GN L1750U GNN AN QP Same model for Service To apply the MSTAR Chip ...

Page 4: ...Blank Page1 ...

Page 5: ...GNAL Refer to the Timing Chart 3 1 Sync Signal Type Separate Sync SOG composite 3 2 Video Input Signal 1 Type R G B Analog 2 Voltage Level 0 0 71 V a Color 0 0 0 Vp p b Color 7 0 0 467 Vp p c Color 15 0 0 714 Vp p 3 Input Impedance 75 Ω 3 3 Operating Frequency Horizontal 30 83kHz Vertical 56 75Hz 4 Max Resolution D sub Analog 1280 x 1024 75Hz 5 POWER SUPPLY 5 1 Power AC 100 240V 50 60Hz 1 2A 5 2 P...

Page 6: ...e module from the ESD as it may damage the electronic circuit C MOS Make certain that treatment person s body are grounded through wrist band Do not leave the module in high temperature and in areas of high humidity for a long time The module not be exposed to the direct sunlight Avoid contact with water as it may a short circuit within the module If the surface of panel become dirty please wipe i...

Page 7: ...st receiver ground lead to the receiver chassis ground before connecting the test receiver positive lead Always remove the test receiver ground lead last 9 Use with this receiver only the test fixtures specified in this service manual CAUTION Do not connect the test fixture ground strap to any heat sink in this receiver Electrostatically Sensitive ES Devices Some semiconductor solid state devices ...

Page 8: ...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 coati...

Page 9: ...onnection 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 t...

Page 10: ...8 600 1 4 23 6 H Pixels 49 5 46 875 1056 800 16 80 160 800 x 600 V Lines 75 0 625 600 1 3 21 7 H Pixels 57 283 49 725 1152 832 32 64 224 832 x 624 V Lines 74 55 667 624 1 3 39 8 H Pixels 65 0 48 363 1344 1024 24 136 160 1024 x 768 V Lines 60 0 806 768 3 6 29 9 H Pixels 78 75 60 123 1312 1024 16 96 176 1024 x 768 V Lines 75 029 800 768 1 3 28 10 H Pixels 100 0 68 681 1456 1152 32 128 144 1152 x 870...

Page 11: ... 1 Remove line 2 3 4 5 6 Remove Al tape from control pcb fix Remove the 4 screws from each side of metal frame 1 Pull the front cover upward 2 Then let the all latches are separated 3 Put the front face down 7 8 Disassembly Tilt swivl Pell off the line ...

Page 12: ...ing ADC LVDS SCALER INPUT SWITCHING TMDS MTV312 MICOM LCD Module R G B differential Adapter 5V APL 5523 12V R G B H V Sync 1 8V 3 3V 1 8V 5V APW 1173 12V 5V LVDS Low Voltage Differential Signaling AC Input BLOCK DIAGRAM 3 3V ...

Page 13: ...s 8 bit R G B signal to transmitter 2 Power Part This part consists of one 5V one 1 8V and 3 3V regulators to convert power which is provided by12V from adapter 12V is provided for inverter mainboard 5V is provided for LCD panel and for micom Also 5V is converted 3 3V and 1 8V by regulator Converted power is provided for IC in the main board The inverter converts from DC12V to AC 700Vrms and opera...

Page 14: ...a bridge rectifier and a bulk capacitor 3 Energy Transfer This part function is transfer the primary energy to secondary through a power transformer 4 Output rectifier and filter This part function is to make a pulse width modulation control and to provide the driver signal to power switch to adjust the duty cycle during different AC input and output loading condition to achive the dc output stabl...

Page 15: ... is available to LCD Monitor only 1 Port Setup a Copy UserPort sys file to c WINNT system32 drivers folder b Run Userport exe c Remove all default number d Add 300 3FF e Click Start button f Click Exit button 2 EDID Read Write 1 Run WinEDID exe 2 Edit Week of Manufacture Year of Manufacture Serial Number a Input User Info Data b Click Update button c Click Write button ...

Page 16: ...display 2 Wait for about 5 seconds and press MENU POWER switch with 1 second interval 3 The SVC OSD menu contains additional menus that the User OSD menu as described below a Auto Color W B balance and Automatically sets the gain and offset value b NVRAM INIT EEPROM initialize 24C08 c CLEAR ETI To initialize using time d AGING Select Aging mode on off e R G B 9300K Allows you to set the R G B 9300...

Page 17: ... U201 NO NO NO OPEN ADAPTER AND FIND OUT A SHORT POINT AS OPENING EACH POWER LINE CHECK U804 PIN 12V LINE OPEN CHECK CHECK 3 3V LINE NO CHECK X TAL YES YES YES YES CHECK THE VOLTAGE OF ADAPTER 12V CHECK U804 PIN 1 Voltage 5V IS U201 PIN90 3 3V VOLTAGE CHECK U201 PIN 96 PULSE 1 NO PROBLEM 1 Waveforms U201 96 ...

Page 18: ...R AND FIND OUT A SHORT POINT AS OPENING EACH POWER LINE CHECK MICOM INV ON OFF PORT 1 CONFIRM BRIGHTNESS OSD CONTRL STATE 2 CHECK MICOM DIM ADJ PORT INVERTER YES YES YES YES J705 PIN6 PIN7 12V J705 PIN1 5V J705 PIN3 WAREFORM CHECK PULSE AS CONTACTING SCOPE PROBE TO CAUTION LABEL CONTACT PROBE TO CAUTION LABEL CAN YOU SEE PULSE AT YOUR SCOPE ...

Page 19: ...ECK U803 15 1 CHECK PIN96 SOLDERING CONDITION 2 CHECK X501 3 TROUBLE IN U201 CHECK CONNECTION LINE FROM D SUB TO U501 YES YES YES U201 PIN 18 90 3 3V U201 PIN96 97 OSCILLATE AS 12MHZ U501 PIN43 IS 48KHz H SYNC PIN44 IS 60Hz V SYNC IS PULSE APPEARED AT SIGNAL PINS AT MODE 12 1 2 1 2 Waveforms U201 96 97 U501 43 H SYNC 2 U501 44 V SYNC ...

Page 20: ...ROUBLE IN DPM TROUBLE IN DPM NO NO TROUBLE IN U501 CHECK PC PC IS NOT GOING INTO DPM OFF MODE CHECK H V SYNC LINE YES YES CHECK R778 R781 CHECK U501 PIN 43 44 SYNC PULSE 3 3 Waveforms R778 H Sync 3 R781 V Sync ...

Page 21: ... 18 WIRING DIAGRAM Connector Ass y P N 68509F0001A Connector Ass y P N 6631T05002A Connector Ass y P N 6631T11025A Connector Ass y P N 6631T11024A ...

Page 22: ...EXPLODED VIEW 19 010 020 070 030 040 090 080 060 050 ...

Page 23: ... KUMI PB FREE EGI SS S D IC EGI 250NITS SXGA LVDS 3809900100A BACK COVER ASSEMBLY L1750U L100 ABS350 9930 BK SILVER BLACK 3809900100B BACK COVER ASSEMBLY L1750U L100 ABS 8B656 WHITE ANALOGUE JP VER 3043900004A TILT SWIVEL ASSEMBLY L1750U TILT STAND BODY SILVER BLACK 3043900005A TILT SWIVEL ASSEMBLY L1750U TILT STAND BASE SILVER BLACK 68719ST052A PWB PCB ASSEMBLY SUB T T CL94 L1750U SNN TT 4950TKS5...

Page 24: ...20 BULK 6 3 5MM 105 C819 0CC221CK41A 220PF 1608 50V 5 R TP NP0 C825 0CK105CD56A 1UF 1608 10V 10 R TP X7R C826 0CK223CK51A 223 1608 50V 10 B Y5P R TP C829 0CK104CK56A 0 1UF 1608 50V 10 R TP X7R C832 0CZZTAB006A KRE RE ST SYE SWE CAP 16V 100UF 20 20 BULK 6 3 5MM 105 DIODEs ICs D701 0DSIH00018A ENKMC2837 T112 LF ISAHAYA R TP SC 59 85V 0 3A 2A 4NSSEC 0 5UA D702 0DSIH00018A ENKMC2837 T112 LF ISAHAYA R ...

Page 25: ...1 10 W 5 1608 R TP R751 0RJ4700D677 470 OHM 1 10 W 5 1608 R TP R752 0RJ1000D677 100 OHM 1 10 W 5 1608 R TP R753 0RJ1000D677 100 OHM 1 10 W 5 1608 R TP R778 0RJ0682D677 68 OHM 1 10 W 5 1608 R TP R781 0RJ0682D677 68 OHM 1 10 W 5 1608 R TP R803 0RH0000D622 0 OHM 1 10 W 2012 5 00 D R804 0RJ1002D677 10K OHM 1 10 W 5 1608 R TP R805 0RH2000D622 200 OHM 1 10 W 5 D R TP R806 0RH2000D622 200 OHM 1 10 W 5 D ...

Page 26: ... 7 8 9 0 1 1 1 2 1 3 1 14 15 16 7 1 8 1 9 1 0 2 21 2 2 3 2 4 2 5 2 6 2 7 2 28 9 2 0 3 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 0 8 9 7 8 7 7 7 6 7 5 7 4 7 3 7 2 7 1 7 0 7 69 8 6 7 6 6 6 5 6 4 6 3 6 2 6 1 6 0 6 59 8 5 7 5 6 5 5 5 4 5 3 5 2 5 1 5 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 100 99 98 97 96 201 U 16AL U S T 201 U 16AL U S T 8 1 2 C 0 01uF 8 1 2 C 0 01uF 8 9 6 0 R2 ...

Page 27: ...0 2 21 2 2 23 4 2 5 2 6 2 7 2 8 2 9 2 0 3 1 3 2 3 3 3 34 35 36 7 3 8 3 39 40 41 2 4 43 4 4 1 0 U5 V M P 2 1 3 TV M 1 0 U5 V M P 2 1 3 TV M F U 01 0 08 5 C F U 01 0 08 5 C 3 0 5 R 4 7K 3 0 5 R 4 7K 1 3 2 3 50 Q 4 0 T39 S K 3 50 Q 4 0 T39 S K 01 5 X Z H M 2 1 01 5 X Z H M 2 1 507 C F 18p 507 C F 18p F p 06 3 5 C F p 06 3 5 C 503 C F U 1 0 0 503 C F U 1 0 0 4 0 5 C V 16 F U 0 1 4 0 5 C V 16 F U 0 1 2...

Page 28: ... 8 R 5 0 8 R 0 0 2 5 0 8 R 0 0 2 1 0 8 L H u 5 1 1 0 8 L H u 5 1 1 2 3 Y 3 7 2 1 A T K 1 0 8 Q 1 2 3 Y 3 7 2 1 A T K 1 0 8 Q 2 3 8 C V 6 1 F U 0 0 1 2 3 8 C V 6 1 F U 0 0 1 1 3 2 2 0 8 Q 4 0 9 3 T S K 2 0 8 Q 4 0 9 3 T S K 0 3 8 C V 6 1 F u 0 1 0 3 8 C V 6 1 F u 0 1 8 2 8 C V 6 1 F u 0 1 8 2 8 C V 6 1 F u 0 1 k 9 3 3 2 8 R k 9 3 3 2 8 R 1 0 8 D 4 3 S S 1 0 8 D 4 3 S S 7 0 8 C V 6 1 F u 0 2 2 7 0 8...

Page 29: ...R F 1u 33 0 7 C F 1u 33 0 7 C F 1u 0 5 73 C F 1u 0 5 73 C ZD711 5 6V ZD711 5 6V 4 0 1uF 3 C7 4 0 1uF 3 C7 8 6 78 7 R 8 6 78 7 R 751 R 0 47 751 R 0 47 0 7 9 C uF 1 0 0 0 7 9 C uF 1 0 0 C744 68pF C744 68pF ZD704 5 6V ZD704 5 6V 02 7 R K 2 02 7 R K 2 3 3 4 R72 3 3 4 R72 8 70 C F 1u 0 0 8 70 C F 1u 0 0 C707 68pF C707 68pF 08 7 R 0 7 4 08 7 R 0 7 4 0 0 5 1 3 R7 0 0 5 1 3 R7 06 R7 5 7 06 R7 5 7 10 9 8 7...

Page 30: ... Y E K G AM D LE R 5V Y0 KE W4 SW4 S 2K 3 R 2K 3 R K 7 4 1 R K 7 4 1 R 1 D Z B 6 5 1 D Z B 6 5 2 C 1u 0 2 C 1u 0 K 1 5 5 R K 1 5 5 R D2 Z 6B 5 D2 Z 6B 5 K 7 4 2 R K 7 4 2 R 5 W S 5 W S K 2 4 R K 2 4 R 1 D E L 1 D E L C1 F u 1 0 C1 F u 1 0 1 W S 1 W S 1 2 3 4 5 6 7 8 0 1 9 1 J H S 5 0 S 0 1 2 1 H F S R H 1 J H S 5 0 S 0 1 2 1 H F S R H 2 W S 2 W S 3 SW3 SW ...

Page 31: ...Mar 2005 P NO 38289S0012A Printed in China ...

Reviews:

No comments

Brands by name

Popular brands

Load more brands