Difficulty: Easy
Correct Answer: Correct
Explanation:
Introduction / Context:The ubiquitous 555 timer is a versatile analog/digital building block. Designers routinely configure it in several modes depending on external resistors, capacitors, and how the threshold/trigger/control pins are wired.
Given Data / Assumptions:
Concept / Approach:Monostable (one-shot): a trigger input causes a single pulse of set width, typically t = 1.1 * R * C. Bistable (latch): by appropriate wiring of the threshold and trigger pins, the 555 acts like an SR latch with set and reset controls. In addition, astable mode provides free-running oscillation, but that does not negate the validity of the other two modes.
Step-by-Step Solution:
Identify monostable: use one timing capacitor and one resistor; apply a negative-going trigger to start a timed pulse.Identify bistable: wire the 555 so that trigger and threshold act as set/reset without an RC timing path.Astable is also common, but the statement asks only about monostable and bistable and is therefore accurate.Conclusion: the statement is correct.Verification / Alternative check:Typical application notes and datasheets include example schematics for monostable, astable, and bistable configurations, confirming the 555’s multi-mode capability.
Why Other Options Are Wrong:Incorrect / only monostable / only astable: These ignore the well-documented versatility of the 555.
Common Pitfalls:Assuming the 555 is only an oscillator. Miswiring control voltage and reset pins can make a monostable behave unreliably.
Final Answer:Correct
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