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LA7837中文资料

LA7853

Overview

The LA7853 is a sync deflection circuit IC dedicated to CRT display use. It can be connected to the LA7832, 7833, 7837, 7838 (for vertical output use) to form a sync deflection circuit that meets every requirement for CRT display use.

So far, ICs for color TV use have been applied to the sync deflection circuit for CRT display use and general-purpose ICs such as one-shot multivibrator, inverter and a lot of transistors have been used to form the peripherals such as sync input interface, horizontal phase shifter. The LA7853 contains these peripherals on chip and adopts a stable circuit

for horizontal oscillation from 15kHz to 100kHz aiming at improving the characteristics requierd for CRT dispaly use. The LA7853 has independent GND pins for the horizontal block and vertical block, thus facilitating pattern layout for applications where the LA7853 is used at high frequencies.

Features

? The vertical pull-in range is approximately 20Hz, 2 times that of the LA7852, at f V = 60Hz. ? The horizontal oscillation frequency can be adjusted stably from 15kHz to 100kHz. ? The horizontal display can be shifted right/left.

? The horizontal/vertical sync input can be used intact regardless of the difference in pulse polarity and pulse width. ? The AFC feedback sawtooth wave can be obtained by simply applying a flyback pulse to the IC as a trigger pulse. ? Any duty of the horizontal pulse can be set.

? Good vertical linearity because DC bias at vertical output stage is subject to sampling control within retrace time.

? Excellent interlace and vertical jitter characteristics on the high-definition display because of independent GND pins for the horizontal block and vertical block.

Functions

[Horizontal Block] [Vertical Block] ? AFC

? Vertical OSC

? Horizontal OSC ? Vertical sawtooth wave generator ? X-ray protector

? Sampling type DC voltage control

? Horizontal phase shift

? AFC sawtooth wave generator ? Horizontal pulse duty setting

Monolithic Linear IC

CRT Display Synchronization

Deflection Circuit

Specifications

Maximum Ratings at Ta = 25°C

Parameter Symbol Conditions Ratings Unit

Maximum supply voltage V 11, V 22

14 V Allowable power dissipation Pd max Ta ≤ 65 °C

780 mW

Operating temperature Topr ?20 to +85 °C Storage temperature

Tstg

?55 to +125

°C

Operating Conditions at Ta = 25°C

Parameter Symbol Conditions Ratings Unit

Recommended supply voltage V 11, V 22

12 V Operating voltage range

V 11, V 22

9 to 13.5

V Recommended vertical pulse input peak value V PULSE 5 Vp-p Operating vertical pulse input peak value range V PULSE 2 to 6

Vp-p Recommended horizontal pulse input peak value H PULSE 5 Vp-p Operating horizontal pulse input peak value range

H PULSE

2 to 6

Vp-p

Electrical Characteristics at Ta = 25°C

Ratings

Parameter Symbol Conditions min typ max

Unit

V CC11 current drain I 11 12 30 mA

V CC22 current drain

I 22 5 12 mA Vertical frequency pull-in range V P IN Vertical sync 60Hz 19.0 23.0 Hz Vertical free-running frequency

fvcenter 55Hz

Increased/reduced voltage characteristic of vertical frequency

?fv.v V 22 = 12 ± 1V, 55Hz at 12V

?0.1 +0.1 Hz

Midpoint control threshold level 3.8 4.4 V Vertical OSC start voltage

fv, st

4.0

Temparature characteristic of vertical frequency Ta = ?10 to +60°C ?0.028

+0.028 Hz/°C

Vertical driver amplification factor Gv

I AFC + 0.85 1.6 mA Horizontal AFC DC loop gain

I AFC ?

?1.6 ?0.85 mA Horizontal free-running frequency f H f H center 15.734kHz ?750

+750

Horizontal OSC start voltage

f H , st

4.0 V

Increased/reduced voltage characteristic of horizontal frequency

?f H , v

V 11 = 12 ± 1V, 15.734kHz at 12V

?50 +50 Hz

Horizontal OSC warm-up drift

?f H 5s. to 30min. after application of power ?50

+50

Temperature characteristic of horizontal frequency Ta = ?10 to +60°C

?2.9 +2.9 Hz/°C

Horizontal output drive current

I 13 6.0 12.0 mA Increased/reduced voltage characteristic of phase shifter delay time

V 11 = 12 ± 1V ?0.5 +0.5 %/V Temperature characteristic of phase shifter delay time Ta = ?10 to +60°C ?0.1 +0.1 %/°C Increased/reduced voltage characteristic of phase shifter pulse width

V 11 = 12 ± 1V ?0.1 +0.1 %/V Temperature characteristic of phase shifter pulse width Ta = ?10 to +60°C

?0.13 +0.13 %/°C AFC phase comparison center time

15.734kHz after F.B.P. input 9.9

11.5

μs

Increased/reduced voltage characteristic of AFC phase comparison center time

V 11 = 12 ± 1V ?1.5 +1.5 %/V Temperature characteristic of AFC phase comparison center time

Ta = ?10 to +60°C

?0.2 +0.2 %/°C Comparison waveform generating input operation voltage

V 5

0.6 0.9 V pin 14 voltage at hold-down operation start

V 14

0.5

0.8 V

Package Dimensions Unit : mm (typ)

3059A

Block Diagram

222

213

204

195

186

177

168

159

12Vertical Osc Phase Shifter Saw Tooth Generator

AFC

Horizontal Osc

X r a y P r o t e c t o r

V CCH

Vertical Ramp Genarator

V CCV

V e r t i c a l p o w e r s u p p l y

V e r t i c a l t r i g g e r i n p u t

V e r t i c a l O S C t i m e c o n s

V e r t i c a l d r i v e o u t p u t

V e r t i c a l G N D

H o r i z o n t a l G N D

X -r a y p r o t e c t i o n i n p u t

H o r i z o n t a l d r i v e o u t p u t

H o r i z o n t a l t r i g g e r i n p u t

N C

F B P t r i g g e r i n p u t

A F C o u t p u t

D i s c h a r g e r e s i s t o r H o r i z o n t a l p o w e r s u p p l y

V e r t i c a l s a w t o o t h w a v e g e n e r a t i o n

M i d p o i n t v o l t a g e c o n t r o l i n p u t

H o r i z o n t a l d r i v e p u l s e w i d t h s e t t i n g

C o m p a r i s o n v o l t a g e g e n e r a t i n g c a p a c i t o r

P h a s e a d j u s t t i m e c o n s t a n t

S y n c p u l s e w i d t h t i m e c o n s t a n t

S a w t o o t h w a v e g e n e r a t i n g c a p a c i t o r

H o r i z o n t a l O S C t i m e c o n s t a n t

This catalog provides information as of June, 2008. Specifications and information herein are subject to change without notice.