TOSHIBA SERVICE MANUAL COLOUR TELEVISION 20VL44 PRINTED IN UK. 2003 C...
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CONTENTS PAGES Safety instructions Technical specifications Panel Specification Chassis block diagram Scaler block diagram Block diagram of power supply Chassis overwiev Service mode items and explanations Data sheet of important IC’s Recommended Part List Frequency list of channels...
SAFETY PRECAUTIONS GENERAL GUIDELINES Always use the manufacturer’s replacement safety components. The critical safety components marked High temperature & high humidity reduce the life-time. with on the schematics diagrams should not be LCD is not proper to be used at high temperature by other substitutes.
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L5A TECHNICAL SPECIFICATION Receiving System PAL B/G+I+D/K SECAM L/L' Comb Filter Adaptive 4H\2H Scaling Upto SXGA at 75Hz Gamma Correction 8 to 10-bit LUT Histogram Equalization Stereo Decoding German A2, Nicam (German A2, Nicam, BTSC) Stereo L, R In Stereo L, R Out Audio Output Power RMS in Max at 10% THD) 2x3W, 2x5W for 22"W Level (1.5, 2.5, Teleweb)
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BLOCK DIAGRAM OF SCALER BAC LIGHT UNIT Panel_En Standby Mute Reset S508 (LVDS) S500(TTL) BR1_ADJ BLK_EN HS/VS LVDS GM 5221 U500 CONNECTOR (20 OR 30 PINS) VGA_RGB (S503,S502) CONTROLLER VGA HS/VS S506 CONN. DAUGHTER BOARD FOR TTL INTERFACES U501 U503 KEYBOARD PARALEL SERIAL FLASH...
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L5A POWER SUPPLY BLOCK DIAGRAM 3.3V-STBY LM1117 S600 V-INV 3.3V +15V-STBY DC Jack 15V,12V F600 +5V-STBY LM2576 LM2576 1.8V-STBY LM1117 U600 U607 1.8V Fuse S602 U605 F601 V-INV V-INV 78L08 2.5V U606 LM117-3.3V 3.3V U604 INPUT: 12V FOR 14,15,17 INCH 5V-STBY U602 15V FOR 20, 22 INCH...
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L5-A Low-to-Mid End LCD-TV BOARD OVERVIEW L5-A Low-to-Mid End LCD TV board incorporates the LCD Controller gm2221, to create a high quality, stand-alone LCD-based TV system for consumer applications. Figure 1 illustrates the Block diagram of the board. This board supposed to have two versions: 1.
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On the board, one high quality video decoder (U100) is provided (VPC3230D of Micronas) to process video inputs coming from the video sources. The video processor can process 3 composite video inputs and 1 S-Cideo input from the NTSC/PAL video sources. The CVBS output recovered from the tuner module is made available to one of the video inputs of the video decoder.
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A keypad connector (S507) is provided which utilizes the integrated low bandwidth ADC in gm2221 for scanning 5-6 keys (menu,V+,V-,P+,P- keys standard- source key optional) on the keypad. The keypad allows access to the OSD without using the remote IR controller. The L5-A board also has In System Programming (ISP) capability for the external flash ROM using DDC2Bi.
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4. GM2221 LCD TV CONTROLLER The gm2221 IC is a highly integrated single channel scaler that can be used for both LCD monitors up to SXGA/UXGA resolutions and rear projection systems with DLP and HTPS LCD engines up to 1280x720 (720P). Some of the key features include: •...
L5A SERVICE MENU Service Menu is entered by pressing 9, 3, 0, 1 keys on the remote controller when the Picture icon is highlighted in the Main Menu. Service Menu has 3 sub-menus. These are: • Options • Adjustments • Selections.
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STAND BY If this Option is OFF, the TV will stay in Stand By mode after a Power On. If this Option is ON, the TV will recall its last stand by status before the Power Off, and switch on from Stand By automatically, if the last state was ‘Stand by On’.
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SELECTIONS This sub-menu contains selections. • TUNER TYPE SAMSUNG / PHILIPS • TELETEXT NO TEXT / FAST / FAST&TOP • MSP CLIP REDUCE VOL / REDUCE TONE / COMPROMISE / DYNAMIC TUNER TYPE One of two supported tuner can be selected from this item. System must be restarted for this change to take effect.
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NORWAY POLAND PORTUGAL SPAIN SWEDEN SWITZERLAND BG + L TURKEY UNITED KINGDOM For countries France, Belgium and Switzerland, autoprogramming is done twice. For Belgium and Switzerland, first BG channels will be searched, after the search in BG is done, searching will restart for L standard.
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DEFAULT OPTIONS/ ITEM NAME VALUES OR VALUES SETUP OPTIONS ON/OFF ON/OFF ON/OFF ON/OFF SCART 2 ON/OFF ON/OFF SVHS ON/OFF HOTEL MODE ON/OFF STBY ON/OFF MSP CARRİER MUTE ON/OFF WSS SCART ON/OFF FIRST ATS ON/OFF BACKLIGHT POL ON/OFF FACTORY MODE ON/OFF ADJUSTMENTS WHITE R 0-255...
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GENESIS GM5221 LCD TV CONTROLLER The gm5221 is an LCD TV controller supporting resolutions up to SXGA (1280x1024). The gm5221 leverages Genesis patented advanced image-processing technology as well as a proven integrated ADC/PLL and an Ultra-Reliable DVI™ compliant digital receiver to provide excellent image quality. gm5221 also integrates a microcontroller, an OSD controller, advanced color management and dual LVDS transmitters.
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1.2 gm5221 Family Features • • Intelligent Image Processing™ Embedded X86 On-chip Microcontroller • • Fully programmable zoom ratios High-performance X86 MCU with on-chip RAM and ROM • • High-quality shrink capability from UXGA resolution External parallel ROM or serial SPI ROM interface •...
Block Diagram CIN1 Adaptive MIXER 2D Scaler Output Y OUT Analog Color Comb Formatter Front End Decoder VIN1 Filter CrCb OUT VIN2 Panorama NTSC, ITU-R 656 Mode YCOE PAL, ITU-R 601 VIN3 SECAL AGC, Contrast FIFO Memory NTSC 2*ADC VIN4 Brightness CNTL Control...
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Video Processing - VPC3230D Pin Name Type Pin Name Type Short Description Short Description B1/CB1IN GND PA SUPPLYD Blue1/Cb1 Analog Component Input Ground, Pad Decoupling Circuitry G1/Y1IN V SUPPA SUPPLYD Green1/Y1 Analog Component Input Supply Voltage, Pad Decoupling Circuitry R1/CR1IN LLC2 Red1/Cr1 Analog Component Input Double Clock Output...
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Video Processing - VPC3230D Pin Name Type Pin Name Type Short Description Short Description Picture Bus Chroma Chroma / Analog Video 5 Input VIN1 Picture Bus Chroma(LSB) Video 1 Analog Input GND SY SUPPLYD Ground, Sync Pad Circuitry VIN2 Video 2 Analog Input V SUPSY SUPPLYD Supply Voltage, Sync Pad Circuitry VIN3 Video 3 Analog Input...
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Audio Processing - MSP3410D Pin Name Type Pin Name Type Short Description Short Description V SUPPA SUPPLYD Not connected Supply Voltage I2C_CL IN/OUT LLC2 I2Cclock Double Clock Output I2C_DA IN/OUT LLC1 IN/OUT I2C data Clock Output I2S_CL IN/OUT V SUPLLCSUPPLYD I2S clock Supply Voltage, LLC Circuitry I2S_WS...
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Audio Processing - MSP3440G Short Description Pin Name Type Pin Name Type Short Description Crystal oscillator GND SY SUPPLYD XTAL_OUT OUT Ground, Sync Pad Circuitry Test pin V SUPSY SUPPLYD Supply Voltage, Sync Pad Circuitry Audio clock output(18.432MHz) INTLC AUD_CL_OUT O UT Interlace Output Active Video Output Not connected...
CONTENTS PAGES Safety instructions Technical specifications Power rating and Panel Specifications Remote control explanations Service Menu of the TV Set appearrances Block diagram of the VCTI Block diagram of Microcontroller (Genesis) Block diagram of power supply Data sheet of important IC’s Service mode items and explanations Replacement part List Frequency list of channels...
SAFETY PRECAUTIONS GENERAL GUIDELINES Always use the manufacturer’s replacement safety components. The critical safety components marked High temperature & high humidity reduce the life-time. with on the schematics diagrams should not be LCD is not proper to be used at high temperature by other substitutes.
SPECIFICATIONS Receiving System PAL B/G+I+D/K SECAM L/L' Tuning System PLL FST Comb Filter Adaptive 4H\2H LTI, CTI Filters Optional Sync On Green (SOG) support on graphics Scaling Upto SXGA at 75Hz Stereo Decoding (German A2, Nicam, BTSC) German A2, Nicam Virtual Dolby Optional Subwoofer...
SERVICE MENU OF THE TV DEFAULT VALUES OR OPTIONS/ VALUES SETUP ITEM NAME OPTIONS SCART 2 ON/OFF ON/OFF SVHS ON/OFF HOTEL MODE ON/OFF STBY RECALL ON/OFF RECALL LAST AV ON/OFF MSP CARRIER MUTE ON/OFF WSS RF ON/OFF AUTO AV 16:9 ON/OFF FIRST ATS ON/OFF...
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LC (L5C) SERVICE MENU Service Menu is entered by pressing 9, 3, 0, 1 keys on the remote controller when the Picture icon is highlighted in the Main Menu. Service Menu has 3 sub-menus. These are: • Options • Adjustments •...
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ADJUSTMENTS This sub-menu contains numeric adjustments. These items are: • WHITE R • WHITE G • WHITE B • BRIGHTNESS • CONTRAST • COLOR • PRESCALE FM • PRESCALE NICAM • PRESCALE SCART • HOTEL VOLUME WHITE R / WHITE G / WHITE B These are used for color bias adjustment.
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MSP CLIP This selection identifies which method will be used by the sound processor to prevent clipping effects on volume. AUTOPROGRAMMING When the user selects the Autoprogram item in Setup menu, Country Selection menu is opened. The user must select a country before the Autoprogramming starts. Broadcast system will be selected according to the country selected.
SET APPEARANCE OF 26-32 INCH Power Supply board Main Back light module Audio Amplifier Chassis (Built-in Panel) SET APPEARANCE OF 15-23 INCH Back light module Main Chassis...
GENESIS GM5221 LCD TV CONTROLLER The gm5221 is an LCD TV controller supporting resolutions up to SXGA (1280x1024). The gm5221 leverages Genesis patented advanced image-processing technology as well as a proven integrated ADC/PLL and an Ultra-Reliable DVI™ compliant digital receiver to provide excellent image quality. gm5221 also integrates a microcontroller, an OSD controller, advanced color management and dual LVDS transmitters.
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1.2 gm5221 Family Features • • Intelligent Image Processing™ Embedded X86 On-chip Microcontroller • • Fully programmable zoom ratios High-performance X86 MCU with on-chip RAM and ROM • • High-quality shrink capability from UXGA resolution External parallel ROM or serial SPI ROM interface •...
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VCT 49xxI Volume 1: General Description General Description 1.1. Features The VCT 49xxI family offers a rich feature set, cover- 1. Introduction ing the whole range of state-of-the-art 50/60-Hz TV applications. The VCT 49xxI is an IC family of high-quality single- –...
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IFIN+ Sound Audio Frontend Processor Demodulator Processor IFIN- PROT HOUT HFLB VERT Comb Color CVBS in Display & Filter Decoder YCrCb in Video Panorama Video Deflection Frontend Scaler Backend RGB in Processor Component RGB out CVBS out Interface RGB in SENSE I2C Master/ Display...
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January 2001 Si9933ADY ® ® Dual P-Channel PowerTrench MOSFET General Description Features This P-Channel MOSFET is a rugged gate version of • –5 A, –20 V, R = 75 mΩ @ V = –4.5 V DS(ON) Fairchild Semiconductor’s advanced PowerTrench = 105 mΩ...
MP1593 3A, 28V Step Down Converter Monolithic Power Systems PRELIMINARY General Description Features The MP1593 is a step-down regulator with an 3A Output Current internal Power MOSFET. achieves Programmable Soft-Start continuous output current over a wide input 100mΩ Internal Power MOSFET Switch supply range with excellent load and line Stable with Low ESR Output Ceramic regulation.
MP1593 3A, 28V Step Down Converter Monolithic Power Systems PRELIMINARY Pin Description BS 1 COMP Exposed Pad on Backside. Connect to Pin 4. Table 1: Pin Designators Name Description High-Side Gate Drive Boost Input. BS supplies the drive for the high-side n-channel MOSFET switch.
REPLACEMENT PART LIST The components which are referred positions may changes by model, size, cosmetic and specification of the LCD TV. Please apply web pages for current part list. The items marked with red are safety components or need to be replaced with original/approved parts.
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PART PART PART DESCRIPTION PART DESCRIPTION NUMBER NUMBER C200 294125R CC-CHIP 100NF K 25V /0603 X7R C448 294125R CC-CHIP 100NF K 25V /0603 X7R C201 294125R CC-CHIP 100NF K 25V /0603 X7R C449 294125R CC-CHIP 100NF K 25V /0603 X7R C202 294125R CC-CHIP 100NF K 25V /0603 X7R...
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PART PART PART DESCRIPTION PART DESCRIPTION NUMBER NUMBER Q311 401142R TRN-CHIP BC858BLT1G SOT23 L324 053804R COIL-CHIP 10UH K 0805 Q312 401142R TRN-CHIP BC858BLT1G SOT23 C386 290475R CC-CHIP 47PF J 50V /0603 NPO TAPE Q313 401142R TRN-CHIP BC858BLT1G SOT23 C387 290475R CC-CHIP 47PF J 50V /0603 NPO TAPE R329 172276R...
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PART PART PART DESCRIPTION PART DESCRIPTION NUMBER NUMBER C403 294234R CC-CHIP 220NF K 16V /0603 X7R C348 251112R EC 10UF 50V RS 11*5 TAPING R=5MM C404 294234R CC-CHIP 220NF K 16V /0603 X7R C419 291337R CC-CHIP 330PF J 50V /0603 NPO C332 294125R CC-CHIP 100NF K 25V /0603 X7R...
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PART PART PART DESCRIPTION PART DESCRIPTION NUMBER NUMBER D608 303867R DIODE-CHIP SL23 DO214AA R105 172224R RC-CHIP 2.2K J 1/16W/0603 TAPE L609 053946R COIL-CHIP B82464G4223M EPCOS R109 173229R RC-CHIP 22K J 1/16W /0603 U600 453553R IC-CHIP MP1593DN-LF-Z DC-DC CONV SOIC8N X52527R CABLE WITH.TERM.L=110MM YEL C600 294125R...