A Reduction of Circuit Size of Digital Direct-Driven Speaker Architecture Using Segmented Pulse Shaping Technique
A Reduction of Circuit Size of Digital Direct-Driven Speaker Architecture Using Segmented Pulse Shaping Technique
复制标题
采用分段脉冲整形技术减小数字直接驱动扬声器架构的电路尺寸
DOI：
10.1109/sips.2017.8109971
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Akira Yasuda
中科院分区：
文献类型：
--
作者：
Shingo Noami;Satoshi Saikatsu;Akira Yasuda
我们提出了一种新颖的数字直接驱动扬声器架构，使用分段脉冲整形技术来减小电路尺寸。数字直驱扬声器由多位delta-sigma调制器和噪声整形动态元件匹配电路组成。由于多位输出直接驱动每个驱动电路，因此系统可以在低电压下高效驱动。然而，扬声器或音圈和驱动电路的数量需要与量化级的数量相同。因此，增加量化级别的数量并不是一个简单的过程。分段脉冲整形技术被提出来在不增加输出单元数量的情况下增加量化级别的数量，从而提高信噪比并减少带外噪声。然而，内部信号处理电路的尺寸增大。我们提出的方法使用噪声整形动态元件匹配电路来减小系统的尺寸。与33级调制器和8个扬声器的传统方法相比，在保持传统方法的信噪比的情况下，该方法查找表的数量减少了27.2%，电路尺寸减少了22.7%。
We propose a novel digital direct-driven speaker architecture using a segmented pulse shaping technique to reduce circuit size. The digital direct-driven speaker consists of a multi-bit delta-sigma modulator and a noise-shaping dynamic element matching circuit. Because the multi-bit outputs drive each of the driver circuits directly, the system can be driven at low voltage with high efficiency. However, it is necessary for the number of loudspeakers or voice coils and driver circuits to be same as the number of quantization levels. Therefore, increasing the number of quantization levels is not a straightforward process. The segmented pulse shaping technique has been proposed to increase the number of quantization levels without increasing the number of output units, thereby improving the signal-to-noise ratio and reducing out-of-band noise. However, the internal signal processing circuit size is increased. Our proposed method reduces the size of the system using a noise-shaping dynamic element matching circuit. Comparing the proposed method with the conventional method for a 33-level modulator and eight speakers, and maintaining the signal-to-noise ratio of the conventional method, the number of look-up table is reduced by 27.2% and the circuit size is reduced by 22.7%.