Enhancing Audio Performance: Noise Reduction and Efficiency in Class AB Amplifier Design

This paper presents the design and optimization of a Class AB Audio Amplifier aimed at high-fidelity applications. A simple and compact Hi-Fi audio amplifier was designed with features to improve the audio quality (power supply regulator, digital volume control, low-frequency driver pre-amplifier, VU meter on display). Key performance specifications such as bandwidth, total harmonic distortion (THD), signal-to-noise ratio (SNR), and output power are thoroughly analyzed to ensure superior audio quality. The study addresses various noise sources, including intrinsic component noise, power supply interference, and inter-stage interference. Advanced techniques to minimize noise and enhance the Power Supply Rejection Ratio (PSRR) are discussed, as well as the usage of high-capacity smoothing capacitors and discrete voltage regulators. The layout design is planned to prevent crosstalk and electromagnetic coupling. Furthermore, the power supply design, incorporating efficient transformers and smoothing capacitors, is optimized for reduced energy consumption and improved PSRR.