multivibraator

A multivibrator is an electronic circuit composed of active components, typically transistors or vacuum tubes, and passive components like resistors and capacitors, designed to generate waveforms or switch between states. These circuits are fundamental in digital electronics and signal processing due to their ability to produce pulses, oscillations, or timing signals. Multivibrators are classified into three primary types: astable, monostable, and bistable, each serving distinct applications.

The astable multivibrator operates in a continuous oscillation mode, alternating between two states without external triggering. It produces a square-wave output and is commonly used in clock generation, timing circuits, and oscillators. The circuit relies on positive feedback to switch between its two states, maintaining a self-sustaining oscillation.

A monostable multivibrator, also known as a one-shot multivibrator, remains stable in one state until triggered by an external input. Upon activation, it switches to the opposite state for a predetermined duration before returning to its initial state. This behavior makes it useful in applications requiring single pulses, such as timing gates, delay generators, and signal indicators.

The bistable multivibrator, or flip-flop, has two stable states and remains in whichever state it is last set. It requires external inputs to switch between states, making it essential for memory storage, data buffering, and sequential logic operations. Bistable multivibrators form the basis of digital memory elements like SR (Set-Reset) and D (Delay) flip-flops.

Multivibrators are constructed using either discrete components or integrated circuits (ICs). Common ICs for multivibrators include the 555 timer, which can function as all three types with appropriate configuration. The design of multivibrators involves careful selection of resistor and capacitor values to achieve desired timing characteristics, such as pulse width or frequency. These circuits are widely used in various electronic systems, from simple timing applications to complex digital signal processing.