Daewoo DTJ-28G8F, Service Manual

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IC description

(4) Pin Description

Pin 1

 - Supply Voltage, Output Pin Driver 

VSUPP*

This pin is used as supply for the following digital output 
pins : FIFORRD, FIFORD, FIFOWR, FIFORWR.

Pin 2

 - Ground, Output Pin Driver 

GNDP*

Output Pin Driver Reference

Pin 3

 - Sync Signal Input 

VS2

Additional pin for the vertical sync information. Via        
Register the used vertical sync can be switched between 
the inputs VS2 and VS(Pin 64)

Pin 4

 - Reset for FIFO Read Counter 

FIFORRD

This signal is active-High and resets the read counter in 
the display frequency doubling FIFO.

Pin 5

 - Read Enable for FIFO 

FIFORD

This signal is active-High and enabels the read counter in 
the display frequency doubling FIFO.

Pin 6

 - Write Enable for FIFO 

FIFOWR

This signal is active-High and enables the write counter in 
the display frequency doubling FIFO.

Pin 7

 - Reset for FIFO Write Counter 

FIFOWR

This signal is active-High and enables the write counter in 
the display frequency doubling FIFO.

Pin 8

 - Horizontal Drive 

HOUT

This open-drain output supplies the drive pulse for the hor-
izontal output stage. A pull-up resistor has to be used.

Pin 9

 - Horizontal Flyback Input 

HFLB

Via this pin, the horizontal flyback pulse is supplied to the 
DDP 3310B.

Pin 10

 - Safety Input 

SAFETY

This input has two thresholds. A signal between the lower 
and upper threshold means normal function. Other signals 
are detected as malfunction.

Pin 11

 - Vertical Protection Input 

VPROT

The vertical protection circuitry prevents the picture tube 
from burn-in in the event of a malfunction of the vertical 
deflection stage. If the peak-to-peak value of the vertical 
sawtooth signal is too small, the RGB output signals are 
blanked.

Pin 12

 - H-Drive Frequency Range Select 

FREQSEL

This pin selects the frequency range for the horizontal 
drive signal.

Pin 13

 - Clock Select 40.5 or 27/32 MHz

CM1

Low level selects 27/32 MHz, High level selects 40.5 MHz

Pin 14

 - Clock Select 40.5 or 27/32 MHz

CM0

Low level selects 27 MHz, High level selects 32 MHz

Pin 15

 - Range Switch2 for Measuring ADC 

RSW2

This pin is an open-drain pull-down output. During cutoff 
measurement the switch is off. During white drive mea-

surement the switch is on. Also during the rest of time it is 
on.

Pin 16

 - Range Switch 1 or Second Input for Measuring 

ADC 

RSW1

This pin is an open-drain pull-down output. During cutoff 

and white-drive measurement, the switch is off. During 
the rest of time it is on. The RSW1 pin can be used as 
second measurement ADC input.

Pin 17

 - Measurement ADC Input 

SENSE

This is the input of the analog to digital converter for the 
picture and tube measurement. Three measurement 
ranges are selectable with RSW1 and RSW2

Pin 18

 - Measurement ADC Reference Input 

MGND

This is the ground reference for the measurement A/D 
converter.

Pin 19

 - Vertical Sawtooth Output 

VERT+(19)

This pin supplies the drive signal for the vertical output 

stage. The drive signal is generated with 15-bit precision. 
The analog voltage is generated by a 4-bit current DAC 
with external resistor (6 k

§

Ù  

for proper operation) and 

uses digital noise-shaping.

Pin 20

 - Vertical Sawtooth Output inverted 

VERT-

This pin supplies the inverted signal of VERT+.

I  C

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