The document discusses sequential logic circuits, distinguishing them from combinational circuits by emphasizing that sequential circuits rely on both current and previous input for output, unlike combinational circuits that only depend on current inputs. It outlines the types of sequential circuits, namely asynchronous and synchronous circuits, highlighting their characteristics such as the use of clock signals and speed differences. Additionally, it mentions basic components used in constructing sequential circuits, like flip-flops, latches, and counters.

1. SEQUENTIAL CIRCUITS
INTRODUCTION

2. Today's Topic
Sequential Logic Circuits
• Introduction

3. Introduction to topic
Combinational circuit:
• It produces an output based on present input variables only
• The previous state of input does not have any effect on the present
state of the circuit
• The combinational circuit does not use any memory.
• Sequential circuit produces an output based on current input and
previous input variables.

4. Sequential circuit
Sequential circuit produces an output based on current input and
previous input variables.
A Sequential circuit combinational logic circuit that consists of
inputs variable (X), logic gates (Combinational/Computational
circuit), output variable (Z) and Memory elements.

5. • The word “Sequential” means that things happen in a
“sequence”, one after another.
• The clock signal actually determines about the things will
happen next.
• Simple sequential logic circuits can be constructed from
standard Bistable circuits such as:
Flip lops, Latches and Counters

6. Types of Sequential Circuits
There are two types of sequential circuit :
 Asynchronous sequential circuit
 Synchronous sequential circuit
Asynchronous sequential circuit Synchronous sequential circuit
1. Do not use a clock signal 1. Uses a clock signal
2. Faster than synchronous sequential 2. They wait for the next clock pulse
circuits because there is no clock pulse to arrive, to perform the next
and change their state immediately operation, so these circuits are
when there is a change in the i/p signal bit slower compared to async.

7. In Next Class
• Flip Flops
• Latches
• Counters

8. • A