High-Order Current-Mode Filters Based on Current Differencing Buffered Amplifiers

In this paper, a current-mode linear transformation (CMLT) filter based on current differencing buffered amplifier (CDBA) is presented. The systematic method is developed to realize CMLT CDBA-based filters efficiently. Based on the proposed design procedures, we can synthesize high-order current-mode filters with CDBAs, grounded resistors and capacitors. A third-order Chebychev lowpass filter is demonstrated. The proposed circuit has been designed with TSMC 0.35 um 2P4M CMOS processes. Simulation results that confirm the theoretical analysis are obtained. Furthermore, the proposed circuits can be extended to high-order filters.