Actual, Fbt Cr-Block E H, Ed’ | Toshiba TW40F80 specs

6-1-3. Actual

Fig. 9-22 shows the actual circuit used in the unit.

A resonant capacitor C0 is also split into two capacitors C443 and C444 in this circuit. The high voltage regulator cirucits is structured by splitting the C443 to two capacitors of C443 and C448.

Here, assume a high voltage increases and the detection volt- age ED' obtained by dividing the high voltage also increases in proportional to the high voltage. This makes the voltage ED increase at pin 7. (The voltage is impedance transformed by a voltage follower circuit consisting of op amplifier Q483 at pin 7.)

The voltage ED and a 9V reference voltage developed by a 3-terminal regulator Q420 are compared. When the ED in- creases, the voltage at pin 2 of Q483 differential amplifier also increases, and the base current IB of the high voltage transistor Q480 increases.

As a result, Q480 collector current increases and Q480 col- lector voltage (at the point B ) decreases. Then, a peak value of VCP2 across C418 is clamped by the diode D443 at the collector voltage lowered, and the collector voltage VCP of Q404 (H output transistor) obtained as a sum of the voltage VCP1 across C443 and VCP2 across L418 decreases. Then, the high voltage also decreases.

When the high voltage lowers, the corrective operation is carried out in reverse order.

*Resustors R451, R452, R453 and R455 are used to cor- rect undersirable influence (H amplitude increase at mini- mum IH) by the H amplidude regulator.

FBT				CR-BLOCK EH

Horizontal	Q404	C443		L462
output	Q404	C443		L462	C440
output				L463	C440
				L463		-27V
				L464		-27V
				L464
		C444	CS
		C444
							R460	125V
					R466			125V
					R466
		C467						R455			ED’
D461					R461/R469		Q462	R455

				L461							R435
				L461
				R463
				R463
					Q460
									Q483		C482
			C464						Q483
			C464				R454
							R454		ED
									ED
										8	6
			D443		R451	R452	R453			8	7
			D443	B	R451	R452					7
		D444							R489
	C418
			C419		Q480	R434		4	R450
						R434	2	4	R450
							2	3
								3
								R488	R490
					R431	R492		R488
					R431	R492					Q420
											Q420
								C483	R494	R439	9V-1
								C483	R494	R439
										R487

Fig. 9-22 Actual high voltage regulator circuit

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Toshiba TW40F80 manual Actual, Fbt Cr-Block E H, Ed’

Contents

TW40F80 Contents Terminal FUNCTION, Description and Block Diagram Wide Aspect Conversion Circuit Failure Analysis Section X Deflection Distortion Correction Circuit Section XI Digital Convergence Circuit Outline Merits of BUS System Section FeatureImproved Serviceability Reduction of Parts Count Specifications Chassis Model Front View Video 3 Inputs Rear View IN-VIDEO Remote Control View 100 Chassis Layout Starsight Newosd FRO. Surr Construction of Chassis Outline Major FeaturesSection II TUNER, IF/MTS/S. PRO Module Circuit Block RF AGC Audio Multiplex Demodulation Circuit A.PRO block diagram A.PRO Section Audio Processor Configuration of the audio circuit and signal flow are given POP Tuner Terminal No Name Operation of Channel Selection Circuit Microcomputer SDA SCL Microcomputer Terminal Function Microcomputer Terminal Name and Operation Logic Terminal Name Function In/Out Logic Remarks On Screen Function EEPROMQA02SDA System Block Diagram Local KEY Detection Method Local key assignment Function Remote Control Code Assignment Code FunctionTo TV set Custom codes are 40-BFH TV set for North U.S.A Code Function Optional Setting for Each Model OPT0 OPT1 Models HEX Entering to Service Mode Test Signal SelectionService Adjustment Failure Diagnosis Procedure Contents to be Confirmed by CustomerExecuting Self Diagnosis Function Understanding Self Diagnosis Indication Self Check Clearing method of self diagnosis result Troubleshooting Chart TV does Not Turned onYES No Acception of KEY-IN No Picture Snow Noise Memory Circuit Check No Indication On Screen Section IV DVD Switch Circuit DVD Switch Block Diagram Outline Circuit Operation ConfigurationSection V WAC Circuit Outline Operation Wide aspect conversion unit block diagram PB6348 Pin Function Pin function of TC9097F QFP 80 pin Names and functions of TC9097F Name Function VFL2 Block Diagram TC9097F system block diagram Wide Aspect Conversion Circuit Failure Analysis Procedures E2PROM OK? Adjustment Method Raster Horizontal One Section 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 section Main/Sub Screen Superimposing Section Main/Sub screen superimposing section QY01 Main IC Terminal FUNCTION, Description and Block DiagramDiagram MPC1832GT QY01 mPC1832GT pin layout QY03 TC9092AF internal block diagram QY03 TC9092AF pin layout QY03 TC9092AF pin list No Pin name Pin function CKW MRD1 QY10/QY11 M518221-30ZS internal block diagram Section VII 3-DIMENSION Y/C Separator Circuit Outline Configuration Circuit DescriptionCircuit Description Terminal description PZ01 Section Viii Vertical Output Circuit Outline Theory of Operation Sawtooth Waveform Generation Output CircuitActual Circuit Circuit Operation Output Output stage power supply voltage Character Correction Up-and Down-ward Extension Correction Linearity Characteristic CorrectionProtection Circuit for V Deflection Stop Up-and Down-ward Linearity Balance UZ22BSD +35V Over Current Protection CircuitTheory of Operation UZ11BSB Raster Position Switching Circuit Ketsu Horizontal Drive Circuit SignalSection IX Horizontal Deflection Circuit Outline Basic Operation of Horizontal Drive On period OFF period Operation of Basic Circuit Signal DEF/POWER PCBHorizontal Output Circuit FBT T3~t4 Description of the basic circuit T1~t2T2~t3 T4~t6 Amplitude Correction Linearity Correction LINCurve Correction S Capacitor Left-right Asymmetrical Correction LIN coil Linearity coil Operation Theory White Peak Bending Correction CircuitOutline EHT Blanking Low Voltage Protection Gate Protector ABL High Voltage Generation CircuitAFC High Voltage DPC Circuit Regulator 1. +210V 2. +35VHigh Voltage High Voltage Circuit CR-BLOCKAnode Actual FBT CR-BLOCK E HED’ RAY Protection Circuit 23 X-RAY protection circuit Over Current Protection Circuit Functions and Features Block Diagram Diode Modulator Circuit OUT Actual 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 Prom ResetMemory PLL Picture Adjustment Service Mode Entering/Exiting Mode Initial screen First screen Second screenSfull Key function of remote control unit ENT Operation 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