Motorola AN485 High Power Audio Amplifiers Application Note

About this manual

This document describes a recommended circuit approach for designing high-performance audio amplifiers capable of delivering 35 to 100 watts of rms power into 4 or 8-ohm loads. The suggested circuitry enables the amplifier to operate safely under any load condition, including a continuous short circuit, by utilizing Motorola's 200-W PNP silicon power transistors in a full-complementary direct-coupled configuration.

What's inside

• Introduction
• Circuit Description
• Short-Circuit Protection
• Semiconductor Complement
• Resistor Values and Power Supply Voltages
• Amplifier Output Load and Transistor Power Dissipation Considerations
• Transistor Heat Sink Requirements

Specifications

Frequently asked questions

What power range do these amplifiers cover?

The amplifiers cover a power range from 35 watts to 100 watts rms.

What load impedances are supported?

The design information supports 4 ohm and 8 ohm load impedances.

Does the circuit include short-circuit protection?

Yes, the circuitry enables the amplifier to operate safely under any load condition, including a continuous short.