The document discusses digital circuits and combinational logic circuits. It describes the types of digital circuits as arithmetic and logic. Logic circuits are further divided into combinational and sequential logic circuits. Combinational circuits are defined as circuits whose outputs only depend on the current inputs, not past inputs. The document outlines the 7 steps to design a combinational circuit and provides examples of common combinational circuits like half adders, full adders, encoders, and decoders. It specifically examines half adders, showing their input/output ports, truth table, and how to derive the logic expressions using K-maps.
The document discusses digital circuits and combinational logic circuits. It describes the types of digital circuits as arithmetic and logic. Logic circuits are further divided into combinational and sequential logic circuits. Combinational circuits are defined as circuits whose outputs only depend on the current inputs, not past inputs. The document outlines the 7 steps to design a combinational circuit and provides examples of common combinational circuits like half adders, full adders, encoders, and decoders. It specifically examines half adders, showing their input/output ports, truth table, and how to derive the logic expressions using K-maps.
The document discusses digital circuits and combinational logic circuits. It describes the types of digital circuits as arithmetic and logic. Logic circuits are further divided into combinational and sequential logic circuits. Combinational circuits are defined as circuits whose outputs only depend on the current inputs, not past inputs. The document outlines the 7 steps to design a combinational circuit and provides examples of common combinational circuits like half adders, full adders, encoders, and decoders. It specifically examines half adders, showing their input/output ports, truth table, and how to derive the logic expressions using K-maps.
The document discusses digital circuits and combinational logic circuits. It describes the types of digital circuits as arithmetic and logic. Logic circuits are further divided into combinational and sequential logic circuits. Combinational circuits are defined as circuits whose outputs only depend on the current inputs, not past inputs. The document outlines the 7 steps to design a combinational circuit and provides examples of common combinational circuits like half adders, full adders, encoders, and decoders. It specifically examines half adders, showing their input/output ports, truth table, and how to derive the logic expressions using K-maps.
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Derive basic gate using NOR gate
Types of digital circuit
1. Arithmetic digital circuit
2. Logic digital circuit
Logic circuit also divided into two part
1. Combinational logic circuit
2. Sequential logic circuit
Arithmetic circuits-
Combinational circuit
Combinational circuit a circuit which output at any time depends only on the input values at that time not depend on past value.
The design of combinational circuit starts from a set of Boolean function and end in a logic circuit diagram
Steps involved in the design of combinational circuit are as follows.
Step-1 state the problem in word
Step-2 finds the number of input and output variables
Step-3 Assign letter symbols to the input and output variables.
Step-4 Obtain the truth table using the word statement.
Step-5 obtains Boolean expression for each output from the truth table.
Step -6 simplify the Boolean expression to minimize the number of variables by
using laws of Boolean algebra or karnaugh map method or McCluskey’s method
Step-7 draws the logic circuit diagram corresponding to the simplified Boolean expression.
Types of combinational circuit
1. Half adder 2. Full adder 3. Half sub-tractor 4. Full sub-tractor 5. Encoder 6. Decoder 7. Multiplexer 8. De-multiplexer
Half adder Half adder is a combinational circuit which perform the arithmetic addition of two binary digits is called half adder .As figure the half adder has two input and two output . The two input are the two 1- bit number A & B and the two output S & C
Above show that figure of half adder and
Input port A & B
Output port S-sum & C- carry
Table – truth table of half adder
k –map method be used for simplifying and derive the expression for half adder
