GENERAL DESCRIPTION
The Z86228 (Line 21 Closed-Caption Controller) is a single I.C. designed to provide the functional performance of a L21C Decoder module. This Superintegration™ VLSI device is completely self contained requiring only composite video, a horizontal timing signal as input and an external keyer (i.e., video switch between TV video and Closed Caption video) to produce captioned video. The Z86228 uses a wired logic approach to perform the functions selected through its input control signals. It is fabricated using standard CMOS technology and designed to achieve the lowest possible cost.