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EL4583
Sync Separator, 50% Slice, S-H, Filter, HOUT
The EL4583 extracts timing from video sync in NTSC, PAL, and SECAM systems, and non standard formats, or from computer graphics operating at higher scan rates. Timing adjustment is via an external resistor. Input without valid vertical interval (no serration pulses) produces a default vertical output.
Outputs are: composite sync, vertical sync, filter, burst/back porch, horizontal, no signal detect, level, and odd/even output (in interlaced scan formats only).
The EL4583 sync slice level is set to the mid-point between sync tip and the blanking level. This 50% point is determined by two internal sample and hold circuits that track sync tip and back porch levels. It provides hum and noise rejection and compensates for input levels of 0.
EL4583 Datasheet
