Sequential and Combinational Circuits

Introduction

• Digital circuits can be classified into two main categories: sequential and combinational.
• These circuits are the building blocks of digital systems, including computers and other electronic devices.

Combinational Circuits

• Definition: A combinational circuit is a type of digital circuit where the output depends only on the current input.
• Characteristics: No memory elements, output is determined solely by the input.
• Examples: Logic gates (AND, OR, NOT), multiplexers, demultiplexers, encoders, and decoders.

Sequential Circuits

• Definition: A sequential circuit is a type of digital circuit where the output depends on both the current input and the previous state of the circuit.
• Characteristics: Has memory elements, output is determined by the input and the current state.
• Examples: Flip-flops, counters, registers, and finite state machines.

Key Differences

• Memory: Combinational circuits do not have memory, while sequential circuits have memory elements.
• Output: Combinational circuit output depends only on the current input, while sequential circuit output depends on both the current input and the previous state.