助听器芯片中的采样率变换数字滤波器设计  

Design of a Sampling Rate Conversion Digital Filter in Hearing Aid Chip

作　　者：兰玉燕 肖宛昂[1,2,3] 王昂 毛文宇 LAN Yuyan;XIAO Wan’ang;WANG Ang;MAO Wenyu(Institute of Semiconductors,Chinese Academy of Sciences,Beijing100083,P.R.China;Center of Mater.Sci.and Optoelec.Engineer.&School of Microelec.,Univ.of Chinese Academy of Sci.,Beijing100049,P.R.China;Beijing Key Laboratory of Radio Frequency Integrated Circuit and System,Beijing100083,P.R.China)

机构地区：[1]中国科学院半导体研究所,北京100083 [2]中国科学院大学材料与光电研究中心&微电子学院,北京100083 [3]射频集成电路与系统北京市重点实验室,北京100083

出　　处：《微电子学》2021年第5期672-677,共6页Microelectronics

基　　金：国家自然科学基金联合基金资助项目(U1936106)。

摘　　要：分析了助听器芯片中Σ-ΔADC的降采样滤波器、上采样滤波器的原理及实现技术。优化滤波器结构和滤波器系数,降低了芯片面积。采用可编程配置的滤波器系数,实现通带平坦度与过渡带带宽、采样率之间的动态切换。采用SMIC 130nm 1P8MCMOS工艺进行了MPW流片验证。结果表明,该滤波器可支持16kHz、32kHz采样率,满足不同采样率助听器DSP的需求。级联后滤波器的通带纹波为0.001dB,阻带衰减达80dB,群延时之和最大值为3.877ms,满足助听器信号转换电路的要求。The principle and implementation ofΣ-ΔADC’s down sampling filter and up sampling filter in the hearing aid chip was presented.Through optimizing the structure and multiplexing the filter’s coefficient,the chip area was reduced.The filter coefficients were programmable to realize the dynamic switching between passband flatness and transition bandwidth as well as the different sampling rate.The circuit was fabricated and verified by MPW in SMIC 130nm 1P8M CMOS process.The results showed that the filter supported 16kHz and 32kHz sampling rates,which could meet the needs of DSP for hearing aid with different sampling rates.The passband ripple of the cascaded filter was 0.001dB,the stopband attenuation was 80dB,and the maximum group delay was 3.877ms.It could meet the requirement of signal conversion circuit of hearing aid.

关 键 词：上采样滤波器 降采样滤波器 CIC滤波器 逆sinc滤波器 半带滤波器 

分 类 号：TN713.7[电子电信—电路与系统]