Toshiba TW40F80 manual Output

Page 61

2-3. V Output

2-3-1. Circuit Operation

The V output circuit consists of a V driver circuit Q302, Pump-up circuit and output circuit Q301, and external circuit components.

(1)Q2 amplifies its input fed from pin 4 of Q301, Q3, Q4 output stage connected in a SEPP amplifies the cur- rent and supplies a sawtooth waveform current to a deflection yoke.

Q3 turns on for first half of the scanning period and allows a positive current to flow into the deflection yoke (Q3 ® DY ® C306 ® R305 ® GND), and Q4 turns on for last half of the scanning period and allows a negative current to flow into the deflection yoke (R305 ® C306 ® DY ® Q4). These operations are shown in Fig. 8-5.

+35V

 

 

 

 

D301

C308

 

 

63V

 

D308

 

V 3

35V

 

 

 

Q301

 

 

 

 

6

3

 

 

GND

 

 

 

 

 

D309

R308

V 7

 

 

 

 

 

Q3

7

 

 

35V

 

 

 

BIAS

 

 

V 2

GND

 

 

 

CIRCUIT

2

 

 

63V

Q2

 

 

 

 

 

 

4

Q4

DY

 

 

 

 

+

 

 

 

 

C306

 

GND

 

 

R305

 

Q3 ON

 

 

 

 

GND

1

 

 

 

 

 

 

 

 

Q4 ON

 

Fig. 8-5

 

 

 

(2)In Fig. 8-6 (a), the power Vcc is expressed as a fixed level, and the positive and negative current flowing into the deflection yoke is a current (d) = current (b) +

(c) in Fig. 8-6, and the emitter voltage of Q3 and Q4 is expressed as (e).

Power Vcc

Q3

i1

Vce 1

Q4

Q2

i2

(a) Basic circuit

(3)Q3 collector loss is i1 x Vce1 and the value is equal to multiplication of Fig. 8-6 (b) and slanted section of Fig. 8-6 (e), and Q4 collector loss is equal to multipli- cation of Fig. 8-6 (c) and dotted section of Fig. 8-6

(e).

GND (b) Q3 Collector current i1

GND (c) Q4 Collector current i2

GND (d) Deflection yoke current i1+i2

Vp

Vcc (e)

1/2 Vcc

GND

Fig. 8-6

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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 LogicEEPROMQA02 On Screen FunctionSDA System Block Diagram Local key assignment Function Local KEY Detection MethodCode Function Remote Control Code AssignmentTo TV set Custom codes are 40-BFH TV set for North U.S.A Code Function OPT0 OPT1 Models HEX Optional Setting for Each ModelTest Signal Selection Entering to Service ModeService Adjustment Contents to be Confirmed by Customer Failure Diagnosis ProcedureExecuting Self Diagnosis Function Self Check Understanding Self Diagnosis IndicationClearing method of self diagnosis result TV does Not Turned on Troubleshooting ChartYES 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 MethodPrinciples of Operation Section VI Dual Circuit OutlineScreen multi-search process 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 Configuration Circuit Description Section VII 3-DIMENSION Y/C Separator Circuit OutlineCircuit 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~t6Linearity Correction LIN Amplitude CorrectionCurve Correction S Capacitor 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 Regulator2. +35V 1. +210VHigh Voltage CR-BLOCK High Voltage CircuitAnode FBT CR-BLOCK E H ActualED’ 23 X-RAY protection circuit RAY Protection CircuitOver Current Protection Circuit Block Diagram Functions and FeaturesOUT Diode Modulator CircuitActual Circuit Later Half Scanning Period Basic Operation and Current PathFirst Half Scanning Period First Half of Scanning Period Later Half of Flyback PeriodP.T Section XI Digital Convergence Circuit Outline Memory ResetProm PLLPicture Adjustment Entering/Exiting Mode Service ModeFirst screen Second screen Initial screenSfull ENT Key function of remote control unitEach Screen Adjustment Method Operation procedureNormal/Full Theater Wide1 Theater Wide 269.5 When Convergence Unit is Replaced When CRT is ReplacedCase Study Adjusting Procedure in Replacing CRT TroubleshootingAdjusting Procedure in Replacing Convergence Unit/Main Def Convergence Output Circuit Convergence Block Diagram Convergence Troubleshooting Chart Main Unit
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