A multivibrator is an electronic circuit that generates continuous square wave or rectangular wave oscillations. It is a type of waveform generator. It is commonly used in electronic circuits for various purposes. (Signal generation, timing, and pulse generation).
There are two main types of multivibrators: astable and monostable.
Contents
Astable Multivibrator:
- An astable multivibrator is a free-running oscillator circuit that continuously switches between two states without any external input.
- It has two distinct voltage levels, typically high and low.
- The circuit consists of two cross-coupled amplifying devices (such as transistors or op-amps) and a feedback network.
- The output waveform is a square wave. It’s an equal amount of time spent with each state.
Monostable Multivibrator:
- A monostable multivibrator, also known as a one-shot multivibrator.
- It has only one stable state.
- Once triggered, it remains in the unstable state for a predetermined period before returning to the stable state.
- Common applications include pulse generators, time delay circuits, and pulse-width modulation.
About Multivibrator
- Astable multi-vibrator is a simple two-state (S1,S2) small electronics device.
- It contains two amplifying transistors and cross coupled by resistors or capacitors.
- During the world was 1, invented the first multivibrator circuit, that is astable multivibrator oscillator, by Henri Abraham (Below Image) and Eugene Bloch during World War I.
- Why called multivibrator?: its output waveform was rich in harmonics, So its called multi vibrator.
The components used in multivibrator circuits can vary, but they typically include resistors, capacitors, and transistors or operational amplifiers (op-amps). Multivibrators find applications in various electronic devices and systems, such as timers, frequency generators, and digital logic circuits.
It’s important to note that with advancements in technology, integrated circuits (ICs) that incorporate This functionality are widely available, simplifying the implementation of such circuits in modern electronic designs.
Basic Astable Multivibrator
- Its is a free-running oscillator circuit that continuously switches between two states without any external input.
- It has two distinct voltage levels, typically high and low.
- The circuit consists of two cross-coupled amplifying devices (such as transistors or op-amps) and a feedback network.
- The output waveform is a square wave with an equal amount of time spent in each state.
Explanation
The following two states are simultaneously changing every-time C1, C2 charge and discharge.
- State 1 : Q1 is switched ON, Q2 is switched OFF.
- State 2 : Q1 is switched OFF, Q2 is switched ON.
Multi-vibrator Applicaion
- It’s used in timers, relaxation oscillators, and flip-flops.
- Square wave generator
- Timed interval application