Multivibrator types — triggering requirement: A monostable multivibrator (one-shot) exhibits which operating characteristic?

Introduction / Context:
Monostable, astable, and bistable multivibrators serve different timing and storage roles. The monostable (one-shot) is used to generate a single pulse of defined width when triggered, making it fundamental in timing, debounce, and pulse-stretch applications.

Given Data / Assumptions:

• Standard one-shot using logic, op-amp comparators, or dedicated ICs (e.g., 555 in monostable mode).
• Defined timing components (R and C) set pulse width.
• Clean triggering edge is provided.

Concept / Approach:
A monostable has one stable state. Upon receiving a trigger, it transitions to a quasi-stable state for a duration T set by circuit parameters, then automatically returns to the stable state. It does not free-run. Bistable devices, by contrast, require inputs to change state and remain there until commanded; astables free-run between states with no stable resting state.

Step-by-Step Solution:

Verification / Alternative check:
Scope measurements show a single pulse following each trigger edge; with no triggers, the output remains in its stable level indefinitely.

Why Other Options Are Wrong:

Common Pitfalls:
Confusing retriggerable vs non-retriggerable modes; ignoring input conditioning and debounce for clean triggering; miscalculating pulse width due to component tolerances.

Final Answer:
It requires an external trigger to enter a temporary quasi-stable state before returning to its stable state