A Sixteen-Color Composite Video Summer Integrated Circuit for Video Display Terminals and Game Systems

This paper describes a monolithic video summer developed by Signetics for video display terminals and game systems capable of accepting NTSC timing signals and a four bit binary code to generate up to 16 separate composite video signals as well as a T2L compatible 3.58 MHz square wave output for genlock or game countdown systems. Video switching speeds and color phase accuracy superior to many competitor products have been achieved. The system concept, basic circuit building blocks, application innovations, and typical performance criteria will all be presented in this paper.