IEEE: Logic Symbols & Diagrams STD 91

ANSI/IEEE Std 91 - 1984 and ANSI/IEEE Std 991 - 1986 provide methods by which engineers, technicians and service people can describe and understand the behavior and implementation of a logic circuit. ANSI/IEEE Std 91 - 1984 provides a way to describe a single logic function with a symbol, enabling users to understand the logic characteristics of these functions or devices without requiring specific knowledge of their internal characteristics. ANSI/IEEE Std 991 - 1986 deals with the selection of symbols, the representation of connections among them, labeling and annotation that further clarify the function of a circuit, and methods by which a circuit diagram may be coordinated with other forms of product documentation.