摘要
为了减小D类放大器,尤其是大功率D类音频放大器的总谐波失真加噪声(THD+N),提出了二阶双反馈闭环结构,有效改善了失真、电源抑制和信噪比等主要性能;通过引入前馈结构,改善了输入信号动态范围。基于CSMC 0.5μm BCD工艺,采用该结构实现的双声道2×10 WD类音频功率放大器采用全差分结构和全桥输出,THD+N低至0.05%,PSRR可达82 dB@1 kHz,效率高于90%。
To improve total harmonics distortion plus noise（THD＋N） of Class D amplifier,especially high power Class D amplifier,a 2nd-order closed loop structure with dual feedback loops was proposed,which helps to achieve sound crucial performances,including distortion,power supply rejection ratio（PSRR） and signal-to-noise ratio（SNR）.Feed-forward structure was also introduced to improve input dynamic range.A differential stereo Class D audio power amplifier based on the proposed architecture was implemented in CSMC＇s 0.5 μm BCD process.With a typical power output of 2×10 W when fully bridged,the circuit had a THD＋N down to 0.05%,a PSRR up to 82 dB @ 1 kHz,and an efficiency above 90%.
出处
《微电子学》
CAS
CSCD
北大核心
2010年第3期406-410,429,共6页
Microelectronics
基金
国家科技重大专项(2009ZX02304-003-01)
