Current-Mode nth-Order Filter Based on a Minimal Component

Abstract

In this paper, a new active current-mode (CM) minimal component, cascaded current differencing unit (CCDU) and a CM nth-order filter based on the CCDU have been presented. The proposed CCDU simplifies the design of the CM nth-order filter circuit considerably. The proposed nth-order circuit, which adopts only an active component and n grounded capacitors, can simultaneously realize low-pass (LP), band-pass (BP) and high-pass (HP) filter responses. It enjoys the simple configuration and is suitable for integrated circuit (IC) fabrication. PSPICE simulations and experimental tests for CM third-order filter based on this structure have also been conducted and the results have good agreement with the theoretical analysis.