SECTION X: DEFLECTION DISTORTION CORRECTION CIRCUIT

(SIDE DPC CIRCUIT)

1. DEFLECTION DISTORTION CORRECTION IC (TA8859CP)

1-1. Outline

The deflection distortion correction IC (TA8859CP), in com- bination with a V/C/D IC (TA1222AN) which has a V pulse output, performs correction for various deflection distortions and V output through the I2C bus control. All the I2C bus controls are carried out by a microcomputer and can be con- trolled with the remote control.

1-2. Functions and Features

The IC has functions of V RAMP voltage generation, V amplitude automatic switching (50/60 Hz), V linearity cor- rection, V amplification, EHT correction, side pincushion correction, I2C bus interface, etc. and controls following items through the I2C bus lines.

(4)V picture position (neutral voltage setting)

(5)V M-character correction

(6)V EHT correction

(7)H amplitude

(8)L and R pin-cushion distortion correction I (entire area)

– Not used for this model.

(9)L and R pin-cushion distortion correction II (corner portions at top and bottom) – Not used for this model.

(10)H trapezoid distortion correction – Not used for this model.

(11)H EHT correction

(12)V AGC time constant switching

(1)

V amplitude

 

 

 

1-3.

Block Diagram

 

 

(2)

V linearity

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(3)

V S-character correction

 

 

Fig. 10-1 shows a block diagram of the basic circuit.

 

 

 

 

 

 

 

 

+9V

 

 

 

 

 

 

 

14

15

16

5

3

 

 

V. Trigger-in

13

Waveform

Trigger

Puise

V. Rame

A G C

V. AGC time

 

 

 

shape

det

Gen.

constant SW

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

control through

 

 

 

 

 

 

 

 

H. trapezoid distortion

 

bus

 

 

 

 

 

 

 

 

 

 

 

 

 

V. M-Character

V. linearity

V. S-character

correction

 

 

 

 

 

 

 

 

 

 

 

correction

correction

correction

L-R pincushion

 

 

 

 

 

 

 

 

 

 

 

 

(Bus Control Signal)

 

 

 

 

 

 

distortion correction I

 

 

 

 

 

 

 

 

 

 

 

 

SDA SCL

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

L-R pincushion

 

 

 

 

 

 

 

V. Amplitude

 

distortion correction II

 

 

 

 

10

 

 

 

(Top & bottom comer section)

 

 

 

 

 

 

Adj.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

9

Logic

 

 

 

 

 

 

 

 

 

 

 

V. screen

V. EHT

H.EHT

 

H.EHT

 

 

 

 

12

 

position

correction

input

 

correction

 

 

 

 

 

 

 

 

 

 

H. Amplitude

2

EW-drive

 

 

 

 

 

 

 

 

Adj.

 

 

 

 

 

8

6

 

1

 

 

4

 

 

 

 

V drive

V. feedback

 

EHT INPUT

EW feedback

 

 

 

 

 

 

Fig. 10-1

 

 

 

 

81

Page 81
Image 81
Toshiba TW40F80 manual Functions and Features, Block Diagram