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ALL ABOUT ELECTRONICS. Some of you might have already heard about
the multivibrator circuits. In electronics, these multivibrator circuits
are widely used. So, in this video, let's quickly understand
about the multivibrator circuits. So, this multivibrator is the electronic circuit
which is used to implement two-state devices like oscillator, timer, and flip-flop. Now, here the two states refer to the two
voltage levels of the multivibrator. Like +15V and 0V. And if we talk in terms of the digital electronics. Then it can be either high or low state. Where here the high state represents the logic
'1' and the low state represents the logic '0'. And depending upon the number of stages the
multivibrator can be divided into three types. Astable, Monostable and bistable multivibrators. So, in Astable Multivibrator, the output will
not remain stable in any of the two states. And if you see the output, the output of the
multivibrator continuously changes between the two states. Now, here the time for which the output remains
in the particular state can be decided by the passive components like a resistor and
the capacitor. And this type of astable multivibrator is
widely used for the design of relaxation oscillator. Then the second type of multivibrator is the
mono-stable multivibrator. And it is also known as the one-shot multivibrator. So, in the monostable multivibrator, there
is one stable state and one astable state. So, in this multivibrator, the output remains
in the stable state. But whenever some external trigger signal
is applied, then output momentarily goes into the unstable state. And after some time, it comes back into the
stable state. So, the time required to come back into the
stable state depends upon the passive components like R and C.
So, by selecting this R and C, we can decide the time for which the output will remain
in the unstable state. So, here let's say, zero volt is the stable
state of this multivibrator and lets 's say 5V is the astable state. And similarly, exactly the opposite is also
possible. Let's say 5V is the stable state of this multivibrator
and whenever some triggering action occurs, the output goes into the unstable state. And let's say that is equal to zero volts. So, this type of multivibrator is widely used
in the timer applications. So, let's say in one particular application
after the certain time from the triggering action one wants to turn on the relay. So, in this type of applications, this monostable
multivibrator is very useful. Then the third type of multivibrator is the
bistable multivibrator. So, in this multivibrator, both states are
the stable states. And the output of the multivibrator can be
in any of the two stable states. So, let's say the initial the output of the
multivibrator is in one stable state. And whenever some triggering action occurs,
then the output will go from one stable state to another stable state. And unless some triggering action occurs,
the output will remain in this second stable state. Now, let's say, after a certain time if once
again some triggering action occurs, then the output will go back into another stable
state. And it will remain in that state, unless and
until once again the triggering action occurs. So, this type of bistable multivibrator is
used in the design of flip-flop. So, these are the three types of multivibrators
which are used in the design of different electronic components. And these three types of multivibrators can
be designed either using an op-amp, transistor or using the 555 timer IC. So, in the future videos, we will see that
how these multivibrators can be designed using these components. So, I hope in this short video, you understood
what is multivibrator and what are different types of multivibrator circuit. So, if you have any question or suggestion
do let me know here in the comment section below. If you like this video, hit the like button
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