为了减小功耗,提高效率,实现电路的集成化、小巧化和贴片化,提出了一种全数字功率放大器设计方案。采用RT9107为功率芯片,再配置优质的二阶低通滤波器,就能构成高性能的双声道全数字功率放大器。该功放器采用I2S总线输入,PWM信号输出方...为了减小功耗,提高效率,实现电路的集成化、小巧化和贴片化,提出了一种全数字功率放大器设计方案。采用RT9107为功率芯片,再配置优质的二阶低通滤波器,就能构成高性能的双声道全数字功率放大器。该功放器采用I2S总线输入,PWM信号输出方式,不但具有元件少,体积小的特点,而且还实现了音频信号的全数字处理。实践表明,此功率放大器的最大输出功率可达2×18 W,总谐波失真度加噪声(THD+N)在3%以下,电路效率可达90%以上,频率响应可达20 Hz^20 k Hz。展开更多
Let S be a closed orientable surface of genus g ≥ 2,and C（S）the curve complex of S.In the paper,we introduce the concepts of 2-path between edges in C（S）,which can be regarded as an analogue to the edge path betw...Let S be a closed orientable surface of genus g ≥ 2,and C（S）the curve complex of S.In the paper,we introduce the concepts of 2-path between edges in C（S）,which can be regarded as an analogue to the edge path between vertices in C（S）.We show that C（S）is 2P-connected,and the 2-diameter of C（S）is infinite.展开更多
文摘为了减小功耗,提高效率,实现电路的集成化、小巧化和贴片化,提出了一种全数字功率放大器设计方案。采用RT9107为功率芯片,再配置优质的二阶低通滤波器,就能构成高性能的双声道全数字功率放大器。该功放器采用I2S总线输入,PWM信号输出方式,不但具有元件少,体积小的特点,而且还实现了音频信号的全数字处理。实践表明,此功率放大器的最大输出功率可达2×18 W,总谐波失真度加噪声(THD+N)在3%以下,电路效率可达90%以上,频率响应可达20 Hz^20 k Hz。
基金Supported by the National Natural Science Foundation of China (Grant No.10931005)
文摘Let S be a closed orientable surface of genus g ≥ 2,and C（S）the curve complex of S.In the paper,we introduce the concepts of 2-path between edges in C（S）,which can be regarded as an analogue to the edge path between vertices in C（S）.We show that C（S）is 2P-connected,and the 2-diameter of C（S）is infinite.
