JSSC 2022第12期Other180nm

A 91 dB THD N Class-D Piezoelectric Speaker Driver Using Dual V oltageCurrent F

采用双电压电流反馈拓扑的D类压电扬声器驱动器，实现低功耗高线性度。

180nm BCD, 4.4A峰值电流, 122mW静态功耗, THD+N -91dB

D类放大器压电扬声器双反馈LC谐振抑制动态电阻匹配

▸创新点1：双电压/电流反馈拓扑（VFB/CFB）通过动态调节反馈路径，有效抑制LC谐振，无需外接阻尼电阻，降低系统功耗（122 mW）和成本，属于系统级创新

▸创新点2：推挽调制（PP-modulated）输出级设计优化开关时序，减少交叉导通损耗，提升效率（驱动4 µF负载/4.4 A峰值电流），属于电路级创新

▸创新点3：动态匹配反馈电阻技术结合斩波器（choppers）抵消电阻失配，将THD+N提升至-91 dB，显著改善线性度，属于方法创新

▸创新点4：BCD 180-nm工艺集成实现高电流驱动能力（4.4 A）与低静态功耗（122 mW）的协同优化，属于工艺-电路协同创新

Abstract

This article presents a Class-D audio ampliﬁer for capacitive piezoelectric speaker loads. Employing a dual voltage feedback (VFB)/current feedback (CFB) topology, the ampliﬁer is capable of damping LC resonance without using an external damping resistor, therefore reducing system power consumption, cost, and size. Additional power savings are achieved by using a push–pull (PP)-modulated output stage. To mitigate linearity degradation due to the mismatch of the feedback resistors, they are dynam