COLOR MONITOR SERVICE MANUAL CHASSIS NO. : CL-29 FACTORY MODEL: LB782G MODEL: ) ID LABEL MODEL No. CAUTION BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. Website:http://biz.LGservice.com E-mail:http://www.LGEservice.com/techsup.html LCD 782LS (LB782G-GD)
WARNING FOR THE SAFETY-RELATED COMPONENT. • There are some special components used in LCD monitor that are important for safety. These parts are marked on the schematic diagram and the replacement parts list. It is essential that these critical parts should be replaced with the manufacturer’s specified parts to prevent electric shock, fire or other hazard.
OPERATING INSTRUCTIONS FRONT VIEW Power ON/OFF Button Power (DPMS) Indicator AUTO Button 1. MENU Button Use this button to enter or exit the on screen display. Button Use these buttons to choose or adjust items in the on screen display <Shortcut Keys>...
BACK COVER REMOVAL ※ Caution: When you open the Back cover, Be careful! Dont stress the Control Board Connector. 1) Set the Monitor face downward. 2) Remove four screws (a). 5) Set the Monitor face upward. 6) Release the up side latch. DISASSEMBLY (b) Latch Point 8) Set the Monitor face downward.
DESCRIPTION OF BLOCK DIAGRAM 1. Input signal part. There is one input which is analog. It comes from 15 pin D-Sub connector. 2. Pre-amp/ ADC / PLL / Video Controller. This part amplifies the level of video signal from the analog video signal to the digital video signal using a pixel clock.
POWER BOARD 50 ~ 60Hz COMPONENTS LINE 100 ~ 240V DESCRIPTION OF BLOCK DIAGRAM 1. EMI components. This part contains of EMI components to comply with global marketing EMI standards like FCC the circuit included a line-filter, across line capacitor and of course the primary protection fuse. 2.
All adjustment are thoroughly checked and corrected when the monitor leaves the factory, but sometimes several minor adjustment may be required. Adjustment should be following procedure and after warming up for a minimum of 10 minutes. • Alignment appliances and tools. - IBM compatible PC - Programmable Signal Generator.
TROUBLESHOOTING GUIDE NO POWER (POWER INDICATOR OFF) CHECK J801 INPUT VOLTAGE (12V) ? CHECK J801 5VST VOLTAGE (5V) ? CHECK U501’s PIN 6. IS THIS PIN OSCILLATED? TROUBLE SOMEWHERE ELSE 1. NO POWER - 12 - TROUBLE IN BULT-IN POWER TROUBLE IN BULT-IN POWER TROUBLE IN...
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2. NO RASTER NO RASTER CHECK J702 PIN 1, 2, 3 (12V) ? CHECK J702 PIN 8 (5V) ? CHECK X501 H. PULSE ? CHECK U201(GM5020) ? CHECK L201, L202, L203 PULSE? TROUBLE IN POWER ADATER or L703, L704 TROUBLE IN INVON PATTERN TROUBLE IN X501...
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3. NO CLOCK (CLOCK GENERATOR) NO DOT CLOCK CHECK X201 24MHz ? CHECK L201 CLOCK ? TROUBLE IN X201 TROUBLE IN U201 - 15 -...
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4. TROUBLE IN DPM TROUBLE IN DPM CHECK R233, R234? CHECK U501 PIN 6 WAVEFORM (24MHz) ? CHECK U501 PIN 11 (0V) ? TROUBLE IN PC CHECK PC PC IS NOT GOING INTO DPM OFF MODE TROUBLE IN X501 TROUBLE IN SIGNAL CABLE - 16 -...
CAUTION: BEFORE REPLACING ANY OF THESE COMPONENTS, READ CAREFULLY THE SAFETY PRECAUTIONS IN THIS MANUAL. * NOTE SAFETY Mark AL ALTERNATIVE PARTS *S *AL LOC. NO. PART NO. DESCRIPTION / SPECIFICATION MAIN BOARD CAPACITORS C201 0CK103CK51A 0.01UF 1608 50V 10% R/TP B(Y5P) C202 0CK103CK51A 0.01UF 1608 50V 10% R/TP B(Y5P)
DIP Package(p) SOIX Package(J) V CC V SS V SS TSSOP Package(U) V SS PIN CONFIGURATION PIN FUNCTION Pin Name Function A0, A1, A2 Device Adress Inputs Serial Data/Address Serial Clock Write Protect +1.8V to + 6.0V power Supply Ground BA033 Low Saturation Voltage type 3-terminal Regulator 1.