Comparator Quiz

An inverting comparator has a reference voltage of VREF​=2V. If the input voltage 1.5V, what will be the output of the comparator?

• Positive saturation voltage

• Negative saturation voltage

• 2 V

• −2 V

An op-amp used as a comparator operates with ±15 V power supplies. What are the possible output voltage levels for this comparator?

• 0 V and 15V

• −15 V and 15V

• −15 V and 0V

• −5 V and 5V

In a non-inverting comparator, VREF=3 V. If VIN=4 V, what will be the output?

• Positive saturation voltage

• Negative saturation voltage

• 4 V

• −3 V

In a comparator circuit without feedback, the output changes:

• Linearly with input voltage

• Asymptotically with input voltage

• Abruptly when the input crosses the reference voltage

• Not at all

In an inverting comparator, if the reference voltage is negative, what happens to the output when the input is more positive than the reference voltage?

• Positive saturation

• Negative saturation

• No output

• Output oscillates

A Schmitt Trigger is essentially:

• A comparator with hysteresis

• A zero-crossing detector

• A window comparator

• A differential amplifier

If an op-amp comparator is powered by ±12V, what is the maximum permissible input voltage range?

• −12V to 12 V

• −10 V to 10V

• −15 Vto 15 V

• Unlimited

Which of the following is an application of an op-amp comparator?

• Analog integrator

• Digital-to-Analog converter

• Voltage level detector

• Current amplifier

An non-inverting op-amp comparator has VREF​=5V and the input VIN=5.5V. The op-amp is powered with ±10V. What is the output voltage?

• 10 V

• −10 V

• 0 V

• 5.5 V

Why is positive feedback often added to comparators?

• To increase the input resistance

• To improve accuracy of the reference voltage

• To introduce hysteresis and prevent oscillations

• To reduce the power consumption