Large input with symmetrical clipping at both peaks: What is the approximate output waveform shape of an amplifier when a large AC input causes equal clipping on both positive and negative peaks?

Introduction / Context:
When an amplifier is overdriven, its output voltage cannot exceed the supply headroom and device limits. The tops and bottoms of the waveform flatten—this is clipping. Understanding the limiting waveform helps predict harmonic content and power dissipation in power electronics and audio systems.

Given Data / Assumptions:

• AC input amplitude is large enough to drive the stage into saturation and cutoff on alternate half-cycles.
• Clipping is symmetrical (both peaks clipped by roughly the same amount).
• The stage is otherwise linear in its central region.

Concept / Approach:

With equal positive and negative clipping, the output transitions quickly between two plateau levels set by the rails and spends little time in the linear mid-region. As the drive increases further, the flat segments dominate. The limiting shape approaches a square wave whose amplitude equals the saturation headroom limits of the stage.

Step-by-Step Solution:

Verification / Alternative check:

Fourier analysis: severe symmetrical clipping produces strong odd harmonics, which is characteristic of square waves, confirming the qualitative prediction.

Why Other Options Are Wrong:

• Sine wave: only when not clipped.
• Triangular wave: arises from slew-rate limiting, not rail clipping.
• Other listed shapes do not match symmetrical hard-limiting behavior.

Common Pitfalls:

• Confusing slew-rate limiting (triangle) with clipping (flat tops).
• Assuming asymmetrical biasing; the prompt states both peaks clip.

Final Answer:

Square wave.