Logic gates and arithmetic circuits are the basic building blocks for developing large and complex systems like Arithmetic Logic Unit (ALU) of a digital computer system. Most of the research groups have reported logic gates and combinational circuits, which responds to only one stimulus namely either electrical or optical signals. This paper reports a novel approach called hybrid approach in realizing electro-optical combinational logic circuits and systems. An electro-optical hybrid logic circuit is defined as a circuit which accepts electrical and/or optical signals and produces both electrical and optical signals. First, hybrid logic function to perform the EX-OR operation is discussed and its functionality has been demonstrated. Later, the hybrid EX-OR gate is used as a basic building block in realizing higher level hybrid combinational arithmetic circuits like hybrid half adder and full adder. These hybrid logic circuits are of great importance, where electrical and optical systems have to coexist namely, computing, communication, instrumentation and control systems. One direct application of these hybrid combinational circuits is in developing hybrid arithmetic unit in a computer system where information can be processed either electrical or/and optical means and have the advantages of both the systems.

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Hybrid Circuits Hybrid Logic Gates Hybrid Opto-electronics Optical Computing Optical Logic Gates