Understanding Monostable Multivibrator States

A monostable multivibrator, also known as a one-shot multivibrator, is a type of unstable electronic circuit that generates a single pulse of a fixed duration when triggered. The key characteristic of a monostable multivibrator is its states. It has one stable state where it rests indefinitely until a trigger signal arrives, and one quasi-stable (or unstable) state where it stays for a predetermined time before returning to its stable state.

Analyzing Monostable Multivibrator Statements

Let's look at the statements provided regarding the states of a monostable multivibrator:

• I. One stable state
• II. One quasi-stable state

Consider statement I: One stable state.

This statement says a monostable multivibrator has one stable state. In the stable state, the circuit remains in a particular output condition indefinitely. It will only change its state when an external trigger pulse is applied. This is a fundamental characteristic of a monostable multivibrator.

Consider statement II: One quasi-stable state.

This statement says a monostable multivibrator has one quasi-stable state. A quasi-stable state is a temporary state. When a trigger pulse is applied to the monostable multivibrator, it leaves its stable state and enters this quasi-stable state. It remains in the quasi-stable state for a duration determined by the circuit components (like resistors and capacitors) and then automatically transitions back to the stable state without needing another trigger. This temporary state is also known as the unstable state.

Based on the definition and operation of a monostable multivibrator, it indeed possesses both one stable state and one quasi-stable state. It rests in the stable state and transitions to the quasi-stable state upon triggering, returning to the stable state after a set time.

Therefore, both statement I and statement II accurately describe the states of a monostable multivibrator.

Hence, the correct option is the one that includes both statements I and II.

Revision Table: Types of Multivibrators and Their States

Additional Information on Monostable Multivibrators

• Triggering: A monostable multivibrator requires an external trigger pulse to transition from its stable state to its quasi-stable state.
• Pulse Generation: The duration of the pulse generated in the quasi-stable state is determined by the values of the timing components (resistors and capacitors) in the circuit.
• Applications: Monostable multivibrators are used in applications requiring timed intervals, pulse shaping, delay generation, and missing pulse detection.