Description

Audio amplifier chips are used in circuits used to process audio signals.

Operation Classes

Class A devices feature a design in which the output stage passes current at all times, even when the input stage is idle.

Class B devices do not pass current when the output device is idle.

Class AB audio amplifier chips combine Class A and Class B operation.

Class C designs are used for radio frequency (RF) transmission.

Class D designs have output devices that are switched on and off at least twice per cycle.

Class E, Class F, Class G, and Class H audio amplifier chips are also commonly available. 

Package Types

• Single in-line package (SIP)
• Dual in-line package (DIP)
• Ceramic DIP (CDIP)
• Plastic DIP (PDIP)
• Small outline IC (SOIC)
• Shrink small outline package (SSOP)
• Small outline package (SOP)
• Chip scale or chip size package (DSP)
• Mini small outline plastic package (MSOP)
• Small outline transistor (SOT)
• Power small outline package (PSOP)
• Thin shrink small outline L-leaded package (TSSOP)
• Quarter size outline package (QSOP)
• Plastic leaded chip carrier (PLCC) 

Specifications

Audio amplifiers carry performance specifications such as operating temperature, output power, supply voltage, and supply current.

Total harmonic distortion (THD) is also an important consideration. With audio amplifier chips, TDH is a measure of the purity of a signal. This value is defined as the ratio of the sum of the powers of harmonic components to the power of the fundamental.

Bandwidth, another important consideration, refers to the ability of an audio amplifier chip to provide a maximum output voltage swing with increasing frequency.

Features

Features are an important consideration when selecting audio amplifier chips. Some products have an embedded reference voltage or on-chip protection against electrostatic discharge (ESD). Others feature rail-to-rail output or rail-to-rail input.

Single supply devices can operate with only one power supply. Audio amplifier chips with an embedded control circuit shut down the device when the temperature exceeds a predefined limit. Audio amplifier chips with embedded current limiters are also commonly available.

Standards

In Europe, ICs must meet the requirements of the Restriction of Hazardous Substances (RoHS) directive.

CEA-490 - This standard defines test conditions and test measurement procedures for determining various performance characteristics of single-channel and multi-channel power amplifiers, pre-amplifiers, integrated amplifiers, receivers, and tuner/pre-amplifiers that use AC mains power.

References

Image Credits:

1-Source Electronic Components