Date: 9 Apr 2013

William Eccles and F.W. Jordan invented the flip-flop from vacuum tubes in 1918. So it was
initially called Eccles-Jordan trigger circuits. The name flip-flop comes may be because of the circuit’s ability to flip from one state to another and back again.

What is Flip-Flop?

Flip-Flop is a sequential circuit that keeps on retaining the binary state until directed by an input signal to change the states. It is a basic unit for storage as it retains the stored information for usage.

A flip-flop is a bistable electronic circuit. It has two stable states: output is either to 0V (logic 0) or +5V dc (logic 1). Flip-Flop is called 1-bit memory unit as it stores only 1-bit information.

A flip-flop is represented by a rectangle with inputs on the left and outputs on the right. One input indicates the normal state and the other output with small-circle indicates the complement output.

Flip-flop is edge triggered. It retains the bit by using the concept known as feedback. That is the output of a circuit is fed back as an input to the same circuit. Basically a flip-flop is a memory element or a storage capable of storing one bit of information.