Sep 082014

What is a Combinational circuit?

combinational circuit is. as its name suggests, a circuit where the output depends only on the “combination” of the inputs at the time we are testing the output.

Analyzing the circuit made of digital gates shown below, the output of each depends only on their inputs. The output F will change if the input A or input B or both at the same time change. Combinational logic circuits are made of basic gates: AND gate, OR gate, NOT gate.

Combinational Circuit

They can also be built with NAND gates, NOR gates, XOR gates, which are a combination of the three basic gates. To understand a combinational logic circuit we can write its boolean equations and its truth table. The boolean equation of the above circuit is:


The truth table of the above circuit is:


Please like & share:

Related Post

NAND Gate – Truth table NAND Gate Theoretically, a NAND gate with two inputs, can be implemented by cascading a two-input AND gate and a NOT gate (or inverter gate). See t...
Digital Logic Levels Digital Logic Levels (hight, low,0,1) In digital circuits is common to say that we have a “high or a “low” logic level at the input or outp...
Logic probe circuit with CD4001 Logic probe circuit with CD4001 IC This logic probe circuit is useful for people who needs an instrument to measure the logic levels on digital circu...
Aiken code – Excess 3 code Aiken code It is recommended to read the tutorial on the binary system before you start reading this tutorial. Aiken BCD code is similar to the na...

 Leave a Reply



You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>