Question

To create a square wave generator using an operational amplifier, the configuration that should be used is:

• A. Integrator
• B. Comparator
• C. Adder
• D. Differentiator

Hint:

Need a square wave? Think comparator — it flips output cleanly between high and low!

Answer 1

The Correct Option is B

A comparator configuration using an op-amp is ideal for generating square waves. In this setup, the op-amp switches its output between the positive and negative supply voltages when the input crosses a reference threshold. This binary-like behavior creates a square waveform at the output.
Often, this is implemented using a Schmitt trigger, which introduces hysteresis to stabilize the transitions and prevent noise from causing false triggering. When combined with a feedback loop and an RC timing network, this forms a classic op-amp-based oscillator capable of generating a continuous square wave.
Why the other options are incorrect:

• (A) Integrators generate ramp or triangular waveforms, not square waves.
• (C) Adders combine multiple signals; they are not used for waveform generation.
• (D) Differentiators respond to changes in signals and generate spikes, not square waves.

Thus, the comparator configuration is the correct and most common approach for producing square waves using an op-amp.