Toshiba TW40F80 manual Section Feature, Outline Merits of BUS System, Improved Serviceability

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SECTION I:

1. FEATURE

The TW40F80 is a first PJ-TV with a wide screen aspect ratio of 16:9 we introduce to North U.S.A. markets.

As the basic chassis N5SS chassis is used.

The future of the model TW40F80 is the use of the N5SS chassis. This chassis introduces a new bus system, devel- oped by the PHILIPS company, called the I2C (or IIC) bus. IIC stands for Inter-Integrated Circuit control. This bus co- ordinates the transfer of data and control between ICs inside the TV. It is a bi-directional serial bus consisting of two lines, named SDA (Serial DATA), and SCL (Serial CLOCK). This bus control system is made possible through the use of digi- tal-to analog converters built into the ICs, allowing them to be addressed and controlled by strings of digital instructions.

The TW40F80 is a first wide TV with a double window sys- tem we introduce to North U.S.A. markets.

The size of the main and sub screens separated in left and right on the screen is the same as each other. So it is possible to enjoy two programs or video and TV program at the same time.

The sub screen is equipped wit 9 screen search function and this is very convenient convenient to search a program you desire.

Note:

Only the different points from the manual “N5SS Chassis” with its file No. 026-9506 are described on this manual. For other parts common with “N5SS Chassis”, please refer to the original manual with its File No. 026- 9506.

OUTLINE

2. MERITS OF BUS SYSTEM

2-1. Improved Serviceability

Most of the adjustments previously made by resetting vari- able resistors and/or capacitors can be made on the new chas- sis by operating the remote control and seeing the results on the TV screen. This allows seeing adjustments to be made without removing servicing speed and efficiency.

2-2. Reduction of Parts Count

The use of digital-to-analog converters built into the ICs, allowing them to be controlled by software, has eliminated or reduced the requirement for many discrete parts such as potentiometers and trimmers, etc.

2-3. Quality Control

This central control of the adjustment data makes it easier to understand, analyze, and review the data, thus improving quality of the product.

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Contents TW40F80 Contents Wide Aspect Conversion Circuit Failure Analysis Terminal FUNCTION, Description and Block DiagramSection XI Digital Convergence Circuit Section X Deflection Distortion Correction CircuitImproved Serviceability Section FeatureOutline Merits of BUS System Reduction of Parts CountChassis Model SpecificationsVideo 3 Inputs Front ViewIN-VIDEO Rear View100 Remote Control ViewStarsight Newosd FRO. Surr Chassis LayoutConstruction of Chassis Section II TUNER, IF/MTS/S. PRO Module Circuit Block Major FeaturesOutline RF AGCAudio Multiplex Demodulation Circuit A.PRO Section Audio Processor A.PRO block diagramConfiguration of the audio circuit and signal flow are given Terminal No Name POP TunerOperation of Channel Selection Circuit SDA SCL MicrocomputerMicrocomputer Terminal Function Terminal Name Function In/Out Logic Remarks Microcomputer Terminal Name and Operation LogicSDA On Screen FunctionEEPROMQA02 System Block Diagram Local key assignment Function Local KEY Detection MethodTo TV set Remote Control Code AssignmentCode Function Custom codes are 40-BFH TV set for North U.S.A Code Function OPT0 OPT1 Models HEX Optional Setting for Each ModelService Adjustment Entering to Service ModeTest Signal Selection Executing Self Diagnosis Function Failure Diagnosis ProcedureContents to be Confirmed by Customer Self Check Understanding Self Diagnosis IndicationClearing method of self diagnosis result YES Troubleshooting ChartTV does Not Turned on No Picture Snow Noise No Acception of KEY-INNo Indication On Screen Memory Circuit CheckSection IV DVD Switch Circuit DVD Switch Block Diagram Outline Section V WAC Circuit Outline ConfigurationCircuit Operation OperationWide aspect conversion unit block diagram PB6348 Pin function of TC9097F QFP 80 pin Pin FunctionName Function Names and functions of TC9097FVFL2 TC9097F system block diagram Block DiagramE2PROM OK? Wide Aspect Conversion Circuit Failure Analysis ProceduresRaster Horizontal One Adjustment MethodScreen multi-search process Section VI Dual Circuit OutlinePrinciples of Operation System Component Diagram of Dual Unit Video/Color/Deflection Process Section OSD Sub screen process section Sub Screen Process SectionMain/Sub screen superimposing section Main/Sub Screen Superimposing SectionDiagram Main IC Terminal FUNCTION, Description and Block DiagramQY01 MPC1832GTQY01 mPC1832GT pin layout QY03 TC9092AF internal block diagram QY03 TC9092AF pin layout CKW QY03 TC9092AF pin list No Pin name Pin functionMRD1 QY10/QY11 M518221-30ZS internal block diagram Circuit Description Section VII 3-DIMENSION Y/C Separator Circuit OutlineConfiguration Circuit Description Terminal description PZ01 Theory of Operation Section Viii Vertical Output Circuit OutlineActual Circuit Output CircuitSawtooth Waveform Generation Circuit OperationOutput Output stage power supply voltage Protection Circuit for V Deflection Stop Linearity Characteristic CorrectionCharacter Correction Up-and Down-ward Extension Correction Up-and Down-ward Linearity BalanceTheory of Operation +35V Over Current Protection CircuitUZ22BSD UZ11BSBKetsu Raster Position Switching CircuitSection IX Horizontal Deflection Circuit Outline SignalHorizontal Drive Circuit Basic Operation of Horizontal DriveOn period OFF period Horizontal Output Circuit Signal DEF/POWER PCBOperation of Basic Circuit FBTT2~t3 Description of the basic circuit T1~t2T3~t4 T4~t6Curve Correction S Capacitor Amplitude CorrectionLinearity Correction LIN Linearity coil Left-right Asymmetrical Correction LIN coilOutline White Peak Bending Correction CircuitOperation Theory EHTBlanking Gate Protector Low Voltage ProtectionAFC High Voltage Generation CircuitABL High Voltage DPC Circuit RegulatorHigh Voltage 1. +210V2. +35V Anode High Voltage CircuitCR-BLOCK ED’ ActualFBT CR-BLOCK E H 23 X-RAY protection circuit RAY Protection CircuitOver Current Protection Circuit Block Diagram Functions and FeaturesOUT Diode Modulator CircuitActual Circuit First Half Scanning Period Basic Operation and Current PathLater Half Scanning Period P.T Later Half of Flyback PeriodFirst Half of Scanning Period Section XI Digital Convergence Circuit Outline Memory ResetProm PLLPicture Adjustment Entering/Exiting Mode Service ModeSfull Initial screenFirst screen Second screen ENT Key function of remote control unitNormal/Full Operation procedureEach Screen Adjustment Method Theater Wide1 Theater Wide 269.5 Case Study When CRT is ReplacedWhen Convergence Unit is Replaced Adjusting Procedure in Replacing Convergence Unit/Main Def TroubleshootingAdjusting Procedure in Replacing CRT Convergence Output Circuit Convergence Block Diagram Convergence Troubleshooting Chart Main Unit