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http://biz.lgservice.com PORTABLE DVD SERVICE MANUAL MODEL : DP271/DP271B/LPA-837 CAUTION BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL. P/NO : AFN33673330 APRIL, 2007...
When servicing this product, under no circumstances should the original design be modified or altered without permission from LG Corporation. All components should be replaced only with types identical to those in the original circuit and their physical location, wiring and lead dress must conform to original layout upon completion of repairs.
SERVICING PRECAUTIONS CAUTION: Before servicing the PORTABLE DVD covered Electrostatically Sensitive (ES) Devices by this service data and its supplements and addends, read Some semiconductor (solid state) devices can be damaged and follow the SAFETY PRECAUTIONS. NOTE: if easily by static electricity. Such components commonly are unforeseen circumstances create conflict between the called Electrostatically Sensitive (ES) Devices.
SPECIFICATIONS • DVD PLAYER Power supply DC 12V (AC adapter terminal), DC 7.4V (Battery) Power consumption 12W with battery Weight 190.4g (0.56kg)(without battery pack) External dimensions(W X D X H) (191 X 74 X 39mm) Signal system NTSL Laser Semiconductor laser, wavelength 655nm (DVD), 790nm(CD) Frequency range (audio) DVD linear sound:48kHZ sampling 4HZ to 20kHZ...
LCD PART 1) Power measuring Measure each power after power supply. C902(-) : -10V, C901(+) : +15V, C916(+) : +7.5V, C918(+) : +5VD, C914 : 3.3V 2) VCOM waveform adjustment Adjust the VCOM level while changing the VR901 as below waveform by using the scope in the C921.
LCD ELECTRICAL TROUBLESHOOTING GUIDE Appear shadow form interference in black background Inverter abnormal Display condition? Fuse Replace Fuse normal? IC(U1) Check and Replace IC(U1) normal operate D907, D901, D902 7.5V, 15V, -10V normal? Main B/D on located IC(U901) Check and Replace +5V normal? Check and Replace RGB signal output?
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LCD ELECTRICAL TROUBLESHOOTING GUIDE LCD MODE CONT signal? MAIN B/D Check All “LOW” (Normal condition? TFT LCD pressure voltage? Power source and D901, D902, U901 Check +15V, -14V, +5V Replace TFT LCD normal? Readjust as adjustement standard Color adjusting normal? Replace and Reassemble Each connector? Replace...
89P_B PANEL T-CON I/F BAT_OUT 3.3V 3.3V 2,3,4,8 PWRCTL_LCD TO SERVO CON18 CON18 LG & MALATA LG & MALATA LG & MALATA Document Number Document Number Document Number 07.LCD I/F 07.LCD I/F 07.LCD I/F Monday, January 15, 2007 Monday, January 15, 2007...
MAIN PART MAIN ELECTRICAL TROUBLESHOOTING GUIDE 1. POWER (DC-DC CONVERTER) CIRCUIT No power on No power on by ADAPTOR by BATTERY Is ADAPTOR Replace ADAPTOR Replace BATTERY BATTERY OK? out 9.5V Replace D606 Is D606 OK. No +18V No +3.3V No +5V No LCD power Is U202...
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MAIN ELECTRICAL TROUBLESHOOTING GUIDE B. AUDIO OUT ABNORMAL C. VIDEO OUT ABNORMAL Audio out abnormal Video out abnormal Check Audio jack & mode Check Video jack & mode Check +9V Check Video signals from MPEG Check signals from MPEG Check IC(U501) Replace IC(U504) Check LC filter D.
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MAIN ELECTRICAL TROUBLESHOOTING GUIDE F. PICTURE ABNORMAL G. DISC ERROR Picture abnormal Disc error Check the disc. Check Disc YES(If OK) Refer to SERVO part Refer to SERVO part YES(If OK) (If OK) Check MPEG_CLK Replace B/D Signal of MPEG part YES(If OK) Check MPEG (IC U201) Replace B/D...
MAIN ELECTRICAL TROUBLESHOOTING GUIDE 2. MPEG CIRCUIT Power is on Does Logo appear Check power & clock. on the screen? Does the Check CD/DVD DSP Is MPEG data Video of the DVD Disc output signal. signal normal? play properly? Check MPEG Decoder input signal.
MAIN ELECTRICAL TROUBLESHOOTING GUIDE 3. RF/SERVO CIRCUIT Laser off Put Disc in. Check the related circuit on Proper RFL signal Disc ID is correct? MT1389 RFL signal . on MT1389? Check the RFL connection between J401 and MT1389. Check DMSO related circuit Proper DMSO signal Does spindle rotate.
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MAIN ELECTRICAL TROUBLESHOOTING GUIDE Proper Check connections between Focus on OK. signals on A, B, C, D MT1389 and pick-up head. of MT1389 Check the related circuit Proper FEO signal on MT1389 FEO sugnal. on MT1389. Check IC(U401) Check the related circuit Proper FEO signal Track on OK.
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MAIN ELECTRICAL TROUBLESHOOTING GUIDE Proper Normal Check Aout_L related circuit Aout_L, Aout_R signal Audio output when Aout_R on MTK1389 disc playback. Check the related circuit of Audio DAC. Check Audio filter, amplify, mute circuit. Commu- Normal nications between Check communi cation lines IR.
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MAIN ELECTRICAL TROUBLESHOOTING GUIDE * CHARGEING CIRCUIT No turn on Red LED Is 8.4V of J602_Pin 1 OK? Is L601 OK? Replace L601. Is IC(U601) OK? Replace IC(U601). Is L602 OK? Replace L602. Is U603 OK? Replace IC(U603). 3-18...
DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING 1. SYSTEM 27MHz CLOCK, RESET & FLASH R/W SIGNAL 1) MT1379 main clock is at 27MHz (X201) FIG 1-1 2. SDRAM CLOCK 1) MT1389 main clock is at 27MHz (R308) DCLK=125MHz, Vp-p=3.7V U301 PIN38 FIG 2-1 3-19...
0.1uF 0.1uF 0.1uF 0.1uF 0.1uF 47uF/10V 47uF/10V EEPROM 24C02 EEPROM 24C02 SOP8 SOP8 LG & MALATA LG & MALATA LG & MALATA Document Number Document Number Document Number 03.MEMORY 03.MEMORY 03.MEMORY Monday, January 15, 2007 Monday, January 15, 2007 Monday, January 15, 2007...
100uF/10V/NC J403 J403 4x1 W/HOUSING 4x1 W/HOUSING MDI1 MDI2 CON4_2.0_DIP_B CON4_2.0_DIP_B LG & MALATA LG & MALATA LG & MALATA Document Number Document Number Document Number 04.OPU & MOTOR 04.OPU & MOTOR Monday, January 15, 2007 Monday, January 15, 2007...
AD_K2 SCLK MPEG I/F C611 C611 C610 C610 0.1uF 0.1uF 0.1uF 0.1uF LG & MALATA LG & MALATA LG & MALATA Document Number Document Number Document Number 06.CHARGE 06.CHARGE 06.CHARGE Monday, January 15, 2007 Monday, January 15, 2007 Monday, January 15, 2007...
ML_OUT MR_OUT R807 R807 MR_OUT CE801 CE801 100uF/10V 100uF/10V AV I/F Q802 Q802 LG & MALATA LG & MALATA LG & MALATA 2SC3356 2SC3356 Document Number Document Number Document Number 08.FM-TX(OPTION) 08.FM-TX(OPTION) 08.FM-TX(OPTION) Monday, January 15, 2007 Monday, January 15, 2007...
8.2K 1% 15K 1% 15K 1% 39K 1% 39K 1% 13K 1% 13K 1% MENU KEY <-> FRONT KEY LG & MALATA LG & MALATA LG & MALATA Document Number Document Number Document Number 10.MENU KEY 10.MENU KEY 10.MENU KEY...