In an op amp comparator circuit, hysteresis primarily does what to input sensitivity?

In an op amp comparator circuit, hysteresis primarily does what to input sensitivity?

• A. Decreases input sensitivity
• B. Increases input sensitivity
• C. Eliminates output saturation
• D. Has no effect on response time

Answer: (A)

Hysteresis adds positive feedback to a comparator, creating two different switching thresholds depending on the current output state. Because of this, the input must move by a finite amount across a band to flip the output, so tiny or noisy fluctuations around a single threshold won’t cause immediate toggling. This makes the circuit less sensitive to small input changes, i.e., input sensitivity is reduced. The output can still saturate when the input crosses its respective threshold, and once the input crosses the higher or lower threshold, the transition happens quickly, but the primary effect here is the reduced sensitivity to small input variations due to the hysteresis band.

Hysteresis adds positive feedback to a comparator, creating two different switching thresholds depending on the current output state. Because of this, the input must move by a finite amount across a band to flip the output, so tiny or noisy fluctuations around a single threshold won’t cause immediate toggling. This makes the circuit less sensitive to small input changes, i.e., input sensitivity is reduced. The output can still saturate when the input crosses its respective threshold, and once the input crosses the higher or lower threshold, the transition happens quickly, but the primary effect here is the reduced sensitivity to small input variations due to the hysteresis band.