Linear - Amplifiers

Linear - Amplifiers - Audio

Image	Part Number	Description / PDF	Quantity	Rfq
	LA4625-P-E Sanyo Semiconductor/ON Semiconductor	IC AMP AB STEREO 13.5W 14SIPHZ	0
	NCP2830MUTXG Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS D MONO 1.2W 20UQFN	0
	FAN3850AUC19X Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS AB MONO 6WLCSP	0
	LA4537M-TE-L-E Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS AB STER 8MW 10MFPS	0
	LV4910T-TLM-E Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS D STEREO 2W 30TSSOP	0
	LV47022P-H Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS AB QUAD 48W 25HZIP	0
	LA4815M-TLM-H Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS AB MONO 1W 8MFP	0
	LA4663-E Sanyo Semiconductor/ON Semiconductor	IC AUDIO AMP BTL 2CH 14SIP	0
	LA4625-E Sanyo Semiconductor/ON Semiconductor	IC AMP AB STEREO 13.5W 14SIPHZ	0
	LA4425A-E Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS AB MONO 6W 5SIPH	0
	NCP2809BDMR2 Sanyo Semiconductor/ON Semiconductor	IC AMP AB STEREO 135MW 10MICRO	0
	FAN7040M Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS AB MONO 3.5W 20SOIC	0
	LV4910T-MPB-E Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS D STEREO 2W 30TSSOP	0
	LV49152V-TLM-E Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS D STER 15W 44SSOPJ	0
	LV4991TT-TLM-E Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS AB MONO 450MW 8MSOP	0
	LA4440J-E Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS AB STEREO 6W 14SIP	0
	FAN3850AUC16X Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS AB MONO 6WLCSP	0
	LA4537MC-BH Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS AB STER 8MW 10SOIC	0
	LV4912GP-TE-L-E Sanyo Semiconductor/ON Semiconductor	IC AMP CLASS D MONO 2W 24VCT	0
	NCP2820FCT1 Sanyo Semiconductor/ON Semiconductor	IC AMP D MONO 2.65W 9FLIPCHIP	0

Linear - Amplifiers - Audio

1. Overview

Linear audio amplifiers are electronic devices designed to amplify low-level audio signals while maintaining signal integrity and minimizing distortion. They operate in the linear region of transistor characteristics, ensuring high-fidelity sound reproduction. These amplifiers are critical in audio systems for applications ranging from consumer electronics to professional audio equipment, enabling clear sound amplification in devices such as smartphones, home theaters, and musical instruments.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Class AB Amplifiers	Combines efficiency of Class B with low distortion of Class A	Home audio systems, guitar amplifiers
Class D Amplifiers	Switching amplifiers with high power efficiency (typically >90%)	Portable speakers, automotive audio systems
Class G/H Amplifiers	Uses multiple power rails to improve efficiency	Professional audio mixers, high-power amplifiers
Class A Amplifiers	Full-cycle conduction with minimal distortion	High-end audiophile equipment, preamplifiers

3. Structure and Components

Typical linear audio amplifiers consist of: - Input Stage: Differential amplifier for signal reception - Gain Stage: Voltage amplification using transistors or op-amps - Output Stage: Push-pull configuration for power delivery - Power Supply: Symmetrical voltage rails ( Vcc) - Thermal Management: Heat sinks or thermal pads for power dissipation Packaged in DIP, SOIC, or surface-mount (SMT) formats with 8-14 pins.

4. Key Technical Specifications

Parameter	Description	Importance
Gain Bandwidth Product (GBW)	Product of amplifier gain and operational bandwidth	Determines frequency response capability
Total Harmonic Distortion + Noise (THD+N)	Measure of signal distortion and noise	Indicates audio quality (typically <0.1%)
Output Power	Maximum power delivered to load (Watts)	Defines application suitability (e.g., 2x15W for stereo)
Power Supply Rejection Ratio (PSRR)	Ability to reject power supply noise	Impacts noise immunity (typically >60dB)
Quiescent Current	Current consumption at no-load condition	Affects power efficiency and thermal design

5. Application Areas

Consumer Electronics: Smartphones, TVs, headphones
Professional Audio: Mixing consoles, studio monitors
Automotive: In-car entertainment systems
Communication: PA systems, VoIP equipment

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Specifications
TI (Texas Instruments)	TPA3255	2x75W Class D amplifier, 102dB PSRR
STMicroelectronics	TDA7294	100W Hi-Fi amplifier, DMOS output stage
Analog Devices	AD822	Low noise JFET input amplifier
NXP Semiconductors	TDA1541A	192kHz DAC with integrated headphone amplifier

7. Selection Guidelines

Key considerations for selection: 1. Application Requirements: Output power, frequency range, and load impedance 2. Power Supply Constraints: Available voltage/current capacity 3. Thermal Management: Operating temperature range and cooling methods 4. Form Factor: Package size for PCB integration 5. Cost vs. Performance: Balancing THD+N, efficiency, and budget

8. Industry Trends

Future developments include: - Increased integration with digital signal processing (DSP) - Adoption of GaN (Gallium Nitride) technology for higher efficiency - Development of AI-powered noise cancellation algorithms - Miniaturization through 3D packaging techniques - Enhanced Class D amplifier designs with reduced electromagnetic interference (EMI)