A 28W -108.9dB/-102.2dB THD/THD+N Hybrid ΔΣ-PWM Class-D Audio Amplifier with 91% Peak Efficiency and Reduced EMI Emission around two-stage feedforward OTAs which together draw 1.8mA from a 1.8V supply. This combination of multilevel quantization together with a high fS results in a loop gain of >76dB (26dB higher than [6]) in the audio band irrespective of process spread, thus ensuring high linearity.

📋 论文概要

该论文提出了一种混合ΔΣ-PWM D类音频放大器，实现了28W输出功率、-108.9dB THD和-102.2dB THD+N，峰值效率达91%，并降低了EMI发射。通过全差分H桥输出级和优化的栅极驱动设计，解决了高效率与低失真之间的权衡问题。

💡 主要创新点

• 采用混合ΔΣ-PWM调制架构，结合了ΔΣ调制的高线性度和PWM的高效率优势。
• 使用N-LDMOS器件和自举电路实现高效栅极驱动，同时通过片上稳压器确保器件安全运行。
• 通过优化输出级和调制策略，显著降低了EMI发射，同时保持高保真度。

🏷 关键词

📄 原文摘要

Lucien Breems2, Marco Berkhout3, Qinwen Fan1, Kofi A.A. Makinwa1 The fully differential H-bridge output stage is shown in Fig. 23.4.1. It consists of four identical N-LDMOS devices (MH and ML) with an RON of ~100m$, which results in >90% peak power efficiency. Schottky diodes (DS) and off-chip bootstrap capacitors (CBS) are used to derive the boosted supply voltages (~14V with respect to VSW) of the MH gate drivers. As the maximum VGS of MH and ML is 5V, on-chip voltage regulators are used to create local 5V supplies relative to the sources of MH and ML, and power the respective gate drivers [7]. Level shifters transmit the control signals from the low-voltage digital domain (DVDD = 1.8V) to the HV domains. AD modulation is used to drive the two halves of the H-bridge, as the resulting outputs are then 180 degrees phase apart, producing significantly lower common-mode (CM) EMI than BD modulation [6]. In general, CM EMI is

👥 作者与机构

Shoubhik Karmakar1, Huajun Zhang1, Robert Van Veldhoven2,