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What is flip-flop????

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Junior Member level 2
Jan 11, 2013
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What is a digital flip-flop and how work it? Give me anyone some conceptual information.

A flip flop changes it's output state from 0 to 1 or vice versa when a pulse is fed to it's input.

It will respond to either rising or falling edge of the pulse depending it is positive or negative edge triggered.

It can store one bit of information and are the basic building blocks of digital electronics.

There are different kind of flip flops like T flip-flop,D flip-flop,SR flip-flop ,JK flip-flop etc. Also we can classify them as synchronous and asynchronous.

How to make it and how it retain one bit data?

Hello avidestroyer,

How to make it

Look for my answer to your question before.

how it retain one bit data?

Look for the circuit.

If the left transistor (T1) is close the output A1 has high level "1".

Through the base resistor (18kΩ) the left transistor (T2) is hold open, because A1 is "1" and T2 gets positive base voltage. So the output A2 has low level "0". Through the base resistor of T1 the base is hold on low level and hold the transistor close.

If you put the input E20 to ground or give a negative pulse, T2 close and A2 changes to "1". At the same time the base of T1 gets also high level from the base resistor. A1 changes to "0". Now the base of T2 is hold on low level by A1. After the input E20 is not more grounded or the negative pulse is gone, this condition is hold until E10 is grounded or gets a negative pulse.

The conditions at the outputs changes, when a negative pulse arrive at the opposite input.



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