As the name indicates, a bistable multivibrator has 2 stable states. It can be switched from one state to another by providing an external trigger. It can be used for storing a binary digit (bit) as it has 2 stable states (0 or 1). So it is commonly used in digital circuits, where it is named as Flip Flop or Latches. A bistable multivibrator can be easily constructed using the most popular and low cost 555 Timer IC.
Multivibrator is a non linear oscillator or function generator which can generate square, rectangular and pulse waves. Monostable Multivibrator or One-Shot Multivibrator has only one stable state. By default monostable multivibrator will be in its stable state, but when triggered it will switch to unstable state (quasi-stable state) for a time period determined by the RC time constant in the circuit.
An Astable Multivibrator is an oscillator circuit that continuously produces rectangular wave without the aid of external triggering. So Astable Multivibrator is also known as Free Running Multivibrator. I have already posted about Astable Multivibrator using Transistors. Astable Multivibrator using 555 Timer is very simple, easy to design, very stable and low cost. It can be used for timing from microseconds to hours. Due to these reasons 555 has a large number of applications and it is a popular IC...
An Astable Multivibrator or a Free Running Multivibrator is the multivibrator which has no stable states. Its output oscillates continuously between its two unstable states without the aid of external triggering. The time period of each states are determined by Resistor Capacitor ( RC ) time constant.
