Toshiba TW40F80 High Voltage Generation Circuit, Afc, Abl, High Voltage DPC Circuit Regulator

Page 75

5. HIGH VOLTAGE GENERATION CIRCUIT

The high voltage generation circuit develops an anode volt- age for the picture tube, focus, screen, CRT heater, video output (210V) and so on by stepping up the pulse voltage developed for flyback period of the horizontal output cir- cuit with the FBT, and supplies the power to various cir- cuit.

5-1. Theory of Operation

Auxiliary

winding

Primary winding

AFC			10
blanking			10
blanking
Heater			9
+12V-1			R448
		C303	R448
			4
+35V			C447
		D302	D408
C310		D302	7
C310			7
			R327
			6
	C460	D460	R469
		D460	R469
-27.5V			5
+210V		D406	R443
+210V			3
			3
+125V	C446
+125V			2
R444
	C448		1
			1

CRT anode

Focus pack

Q404	C440	C443	C444	ABL
	C440	C443	C444
T401
C463				H deflection coil	1H
	C418		C467	L462/L463/L464	(15.625kHz)
				L462/L463/L464

			L441	R441
			L441
				C423
HIGH VOLTAGE		DPC CIRCUIT
REGULATOR
CIRCUIT

1040V(p-p)

Fig. 9-15

75

Image 75

Contents TW40F80 Contents Wide Aspect Conversion Circuit Failure Analysis Terminal FUNCTION, Description and Block DiagramSection XI Digital Convergence Circuit Section X Deflection Distortion Correction CircuitReduction of Parts Count Section FeatureImproved Serviceability Outline Merits of BUS SystemChassis Model SpecificationsVideo 3 Inputs Front ViewIN-VIDEO Rear View100 Remote Control ViewStarsight Newosd FRO. Surr Chassis LayoutConstruction of Chassis RF AGC Major FeaturesSection II TUNER, IF/MTS/S. PRO Module Circuit Block OutlineAudio 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 LogicOn Screen Function EEPROMQA02SDA System Block Diagram Local key assignment Function Local KEY Detection MethodRemote Control Code Assignment Code FunctionTo TV set Custom codes are 40-BFH TV set for North U.S.A Code Function OPT0 OPT1 Models HEX Optional Setting for Each ModelEntering to Service Mode Test Signal SelectionService Adjustment Failure Diagnosis Procedure Contents to be Confirmed by CustomerExecuting Self Diagnosis Function Self Check Understanding Self Diagnosis IndicationClearing method of self diagnosis result Troubleshooting Chart TV does Not Turned onYES No Picture Snow Noise No Acception of KEY-INNo Indication On Screen Memory Circuit CheckSection IV DVD Switch Circuit DVD Switch Block Diagram Outline Operation ConfigurationSection V WAC Circuit Outline Circuit 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 MethodSection VI Dual Circuit Outline Principles of OperationScreen 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 SectionMPC1832GT Main IC Terminal FUNCTION, Description and Block DiagramDiagram QY01QY01 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 Section VII 3-DIMENSION Y/C Separator Circuit Outline Configuration Circuit DescriptionCircuit Description Terminal description PZ01 Theory of Operation Section Viii Vertical Output Circuit OutlineCircuit Operation Output CircuitActual Circuit Sawtooth Waveform GenerationOutput Output stage power supply voltage Up-and Down-ward Linearity Balance Linearity Characteristic CorrectionProtection Circuit for V Deflection Stop Character Correction Up-and Down-ward Extension CorrectionUZ11BSB +35V Over Current Protection CircuitTheory of Operation UZ22BSDKetsu Raster Position Switching CircuitBasic Operation of Horizontal Drive SignalSection IX Horizontal Deflection Circuit Outline Horizontal Drive CircuitOn period OFF period FBT Signal DEF/POWER PCBHorizontal Output Circuit Operation of Basic CircuitT4~t6 Description of the basic circuit T1~t2T2~t3 T3~t4Amplitude Correction Linearity Correction LINCurve Correction S Capacitor Linearity coil Left-right Asymmetrical Correction LIN coilEHT White Peak Bending Correction CircuitOutline Operation TheoryBlanking Gate Protector Low Voltage ProtectionHigh Voltage DPC Circuit Regulator High Voltage Generation CircuitAFC ABL1. +210V 2. +35VHigh Voltage High Voltage Circuit CR-BLOCKAnode Actual FBT CR-BLOCK E HED’ 23 X-RAY protection circuit RAY Protection CircuitOver Current Protection Circuit Block Diagram Functions and FeaturesOUT Diode Modulator CircuitActual Circuit Basic Operation and Current Path Later Half Scanning PeriodFirst Half Scanning Period Later Half of Flyback Period First Half of Scanning PeriodP.T Section XI Digital Convergence Circuit Outline PLL ResetMemory PromPicture Adjustment Entering/Exiting Mode Service ModeInitial screen First screen Second screenSfull ENT Key function of remote control unitOperation procedure Each Screen Adjustment MethodNormal/Full Theater Wide1 Theater Wide 269.5 When CRT is Replaced When Convergence Unit is ReplacedCase Study Troubleshooting Adjusting Procedure in Replacing CRTAdjusting Procedure in Replacing Convergence Unit/Main Def Convergence Output Circuit Convergence Block Diagram Convergence Troubleshooting Chart Main Unit