Digital Logic Design
Digital electronic circuits operate with voltages of two logic levels namely Logic Low and Logic High. The range of voltages corresponding to Logic Low is represented with ‘0’. Similarly, the range of voltages corresponding to Logic High is represented with ‘1’.
The basic digital electronic circuit that has one or more inputs and single output is known as Logic gate. Hence, the Logic gates are the building blocks of any digital system. We can classify these Logic gates into the following three categories.
The basic digital electronic circuit that has one or more inputs and single output is known as Logic gate. Hence, the Logic gates are the building blocks of any digital system. We can classify these Logic gates into the following three categories.
- Basic gates
- Universal gates
- Special gates
Basic Gates
In earlier chapters, we learnt that the Boolean functions can be represented either in sum of products form or in product of sums form based on the requirement. So, we can implement these Boolean functions by using basic gates. The basic gates are AND, OR & NOT gates.
In earlier chapters, we learnt that the Boolean functions can be represented either in sum of products form or in product of sums form based on the requirement. So, we can implement these Boolean functions by using basic gates. The basic gates are AND, OR & NOT gates.
AND gate
An AND gate is a digital circuit that has two or more inputs and produces an output, which is the logical AND of all those inputs. It is optional to represent the Logical AND with the symbol ‘.’.
The following table shows the truth table of 2-input AND gate.
An AND gate is a digital circuit that has two or more inputs and produces an output, which is the logical AND of all those inputs. It is optional to represent the Logical AND with the symbol ‘.’.
The following table shows the truth table of 2-input AND gate.
Here A, B are the inputs and Y is the output of two input AND gate. If both inputs are ‘1’, then only the output, Y is ‘1’. For remaining combinations of inputs, the output, Y is ‘0’.
The following figure shows the symbol of an AND gate, which is having two inputs A, B and one output, Y.
The following figure shows the symbol of an AND gate, which is having two inputs A, B and one output, Y.
This AND gate produces an output Y, which is the logical AND of two inputs A, B. Similarly, if there are ‘n’ inputs, then the AND gate produces an output, which is the logical AND of all those inputs. That means, the output of AND gate will be ‘1’, when all the inputs are ‘1’.
OR gate
An OR gate is a digital circuit that has two or more inputs and produces an output, which is the logical OR of all those inputs. This logical OR is represented with the symbol ‘+’.
The following table shows the truth table of 2-input OR gate.
OR gate
An OR gate is a digital circuit that has two or more inputs and produces an output, which is the logical OR of all those inputs. This logical OR is represented with the symbol ‘+’.
The following table shows the truth table of 2-input OR gate.
Here A, B are the inputs and Y is the output of two input OR gate. If both inputs are ‘0’, then only the output, Y is ‘0’. For remaining combinations of inputs, the output, Y is ‘1’.
The following figure shows the symbol of an OR gate, which is having two inputs A, B and one output, Y.
The following figure shows the symbol of an OR gate, which is having two inputs A, B and one output, Y.
Need more information then download the material by clicking on Download Here Button!
© Copyright Protected.