Schmitt trigger characteristics: A Schmitt trigger employs positive feedback to create two distinct switching thresholds (hysteresis), thereby cleaning up noisy or slowly changing input signals. Judge the accuracy of this statement.

Introduction / Context:
Schmitt triggers are ubiquitous in digital interfaces where inputs may rise or fall slowly, or where noise could cause spurious toggling. By adding hysteresis, these devices enforce clean transitions and reduce chatter at threshold.

Given Data / Assumptions:

• Input may be noisy or have a slow slew rate.
• Schmitt trigger topology includes positive feedback.
• Two thresholds exist: one for rising input, one for falling input.

Concept / Approach:
Positive feedback shifts the effective switching threshold depending on the current output state. This produces hysteresis: V_T+ (rising) and V_T− (falling), with V_T+ > V_T−. The gap between these thresholds filters input noise within that band and ensures the output changes state only once per valid crossing.

Step-by-Step Solution:
Model the trigger as a comparator/inverter with resistive feedback.Derive that the input threshold depends on output level through feedback division.Observe distinct rising vs falling trip points.Conclude that hysteresis stems from the intentional positive feedback.

Verification / Alternative check:
Datasheets for logic families with Schmitt inputs (e.g., 74HC14) specify separate V_T+ and V_T−, confirming hysteresis behavior.

Why Other Options Are Wrong:
“Incorrect” disregards the defining feature. The behavior holds for both inverting and noninverting forms and across low-voltage logic, not only above arbitrary voltages.

Common Pitfalls:
Assuming hysteresis means memory beyond thresholds; in fact, it is immediate state-dependent thresholding. Overlooking that hysteresis width affects noise immunity and timing.

Final Answer:
Correct