September 1990

2

Philips Semiconductors

Preliminary specification

Horizontal/vertical synchronization

circuit

TDA2579B

GENERAL DESCRIPTION

The TDA2579B generates and synchronizes horizontal and vertical signals. The device has a 3 level sandcastle output;

a transmitter identification signal and also 50/60 Hz identification.

Features

• Horizontal phase detector, (sync to oscillator), sync separator and noise inverter

• Triple current source in the phase detector with automatic selection

• Second phase detector for storage compensation of the horizontal output

• Stabilized direct starting of the horizontal oscillator and output stage from mains supply

• Horizontal output pulse with constant duty cycle value of 29 µs

• Internal vertical sync separator, and two integration selection times

• Divider system with three different reset enable windows

• Synchronization is set to 628 divider ratio when no vertical sync pulses and no video transmitter is identified

• Vertical comparator with a low DC feedback signal

• 50/60 Hz identification output combined with mute function

• Automatic amplitude adjustment for 50 and 60 Hz and blanking pulse duration

• Automatic adaption of the burst-key pulsewidth

PACKAGE OUTLINE

18-lead dual in line; plastic (SOT 102); SOT102-1; 1996 November 19.