Two Class-D Audio Amplifiers with 89/90% Efficiency and 0.02/0.03% THD+N Consuming Less than 1mW of Quiescent Power

📋 论文概要

本文提出了两种Class-D音频放大器，实现了89%和90%的高效率，以及0.02%和0.03%的极低总谐波失真加噪声（THD+N），同时静态功耗低于1mW。通过创新的调制方案取代传统PWM中的高精度载波生成，解决了低功耗下实现低失真的难题。

💡 主要创新点

• 提出新型低功耗调制器架构，省去高精度载波发生器，显著降低静态功耗。
• 在保持高效率的同时，通过优化调制策略将THD+N降至0.02%/0.03%，实现了效率与失真的良好平衡。

🏷 关键词

📄 原文摘要

The high efficiency of Class-D amplifiers (CDAs) makes them highly attractive candidates for audio drivers in systems with extremely low-power requirements. However, to achieve low distortion, the audio modulator is usually complex and power hungry. Conventional CDAs based on pulsewidth modulation (PWM) architectures [1,2] require generation of a highly accurate carrier signal, because any nonlinearity present in that wave will impact the distortion of the amplifier. Since the carrier wave is ideally a periodic signal with infinitely many harmonic components, the design of the ramp generator will require highly accurate circuitry, increasing the complexity and power consumption of the overall system. On the other hand, high-performance topologies based on conventional ∆Σ modulators must be modified to avoid instability and to improve efficiency [3], thus resulting in amplifiers unsuitable for battery-powered applications. Other

👥 作者与机构

Miguel A. Rojas-González, Edgar Sánchez-Sinencio

Texas A&M University, College Station, TX