When used as a comparator, an op-amp is wired in a closed-loop configuration.

More Questions from Basic Op-Amp Circuits

• To operate properly, an oscillator requires an external ac input signal.
• The output voltage of a summing amplifier is proportional to the product of the input voltages.
• The effectiveness of a filter in rejecting signals beyond cutoff frequency is a function of the filter roll-off rating.
• For a Wien-bridge oscillator to produce a sustained sine-wave output, the phase shift around the positive feedback loop must be greater than 0°.
• A two-pole active filter produces a roll-off rate of –20 dB/decade.
• The control element in a basic shunt voltage regulator is a zener diode.
• A Wien-bridge oscillator uses _________.
• In order to sustain oscillations in a feedback oscillator, the gain should be _________ so the Acl _______.
• The reference voltage for the comparator in the given circuit equals ______.
• In the given circuit, VIN1 equals ______.

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