Understanding Ferrite Inductors in Class D Amplifier Design:

Class D audio amplifiers continue to grow in popularity, powering everything from portable Bluetooth speakers to high-performance home audio systems. Their appeal is clear: they’re efficient, compact, and capable of delivering impressive sound.

But behind every great Class D amplifier is one small component that plays a big role — the output inductor.

Our latest application note introduces designers to how ferrite-based inductors fit into the Class D signal path and why they matter. Whether you’re new to Class D technology or simply exploring ways to get better audio performance, this guide offers a friendly, approachable overview of the fundamentals.

Why Focus on the Output Inductor?

In a Class D amplifier, the output inductor helps turn the amplifier’s high-frequency switching signal into clean, listenable audio. While that function sounds simple, choosing the right inductor can influence:

• Sound quality
• Power efficiency
• Thermal performance
• EMI behavior

Our application note walks through these ideas in a clear and accessible way — no heavy equations required.

What You’ll Learn in the Application Note

The document gives readers a practical look at:

• The role of ferrite materials in audio designs
• How inductors help maintain clean, stable audio output
• What matters most when selecting an inductor for a Class D amplifier
• A real-world example using a popular 150 W design

It’s a great starting point for engineers, product designers, and anyone who wants to understand the building blocks behind modern audio systems.

The 1D Series: Designed for Class D Amplifiers

The application note also introduces our 1D Series inductors, created specifically for Class D audio applications. With compact form factors, high reliability, and materials optimized for switching-audio performance, the series gives designers a simple, dependable building block for new and existing projects.

Download the Full Application Note

If you’re looking for a straightforward, helpful introduction to output inductors in Class D amplifiers, this application note is a great place to begin.

Download: Applying Ferrite-Based Inductors in the Design of Class D Amplifiers

Go to Application Notes page.

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