Applications of Op Amp

Which of the following is the primary function of a comparator circuit in industrial applications?

• Amplification

• Analog to digital conversion

• Comparing two voltages and switching output accordingly

• Filtering noise

Which component is most commonly used as the core of a comparator circuit?

• Transformer

• Operational amplifier

• Inductor

• Diode

A Schmitt trigger is preferred over a simple comparator in industrial environments because:

• It amplifies signals

• It provides hysteresis, reducing false triggering due to noise

• It works only with digital signals

• It requires no power supply

What is the main characteristic of a Schmitt trigger circuit?

• Single threshold voltage

• Two distinct switching threshold voltages (hysteresis)

• Zero output impedance

• Linear transfer characteristic

Precision rectifiers are used in industrial measurement systems because they:

• Work at high voltages only

• Can rectify small signals accurately without diode voltage drop errors

• Are cheaper than standard rectifiers

• Do not require operational amplifiers

Which filter attenuates any frequency outside a specific range (pass band)?

• Low-pass filter

• High-pass filter

• Band-pass filter

• Band-reject filter

A Butterworth filter is also known as a:

• Flat-flat filter

• Ripple filter

• Chebyshev filter

• Notch filter

The critical (cut-off) frequency of a filter is defined as the point where the output drops to:

• 50% of maximum amplitude

• 0.707 of maximum amplitude (3 dB point)

• 0.5 of input voltage

• Zero

Which filter type has two stop bands?

• Band-pass filter

• Low-pass filter

• High-pass filter

• Band-reject filter

For a band-pass filter with a center frequency of 1 kHz and a bandwidth of 200 Hz, the quality factor (Q) is:

• 0.2

• 2

• 5

• 10