Design and Implementation of Low Resource Consumption Low Pass Filter Based on Parallel CIC
Zhiyu Zheng, Kuojun Yang, Wuhuang Huang, Ruiyuan Ming, Hehe Liu, Pengfei Zhang, Jingjing Luo, Yuanhang Wang · 2025
Modern signal testing instruments are continuously evolving towards higher bandwidths and sampling rates to meet the diverse demands across various fields. However, in most application scenarios, the effective components of the test signal do not require such high bandwidths. When the instrument captures signals across the entire bandwidth range, additional noise is inevitably introduced, which affects the accuracy of the measurements. Therefore, the bandwidth-limiting function of the instrument becomes crucial. This paper proposes a method to achieve digital bandwidth-limiting low-pass filtering using a parallel CIC filter: by adjusting the delay of the CIC filter for filtering and designing a parallel CIC structure. This parallel CIC structure can realize 20 MHz low-pass filtering at a 10 GSPS sampling rate without consuming multipliers, using only a small amount of LUT resources. This method can achieve highperformance low-pass filtering with tight resource constraints.