Minimum Component Truly Mixed Mode First Order Universal Filter Employing EXCCTA

Abstract

A mixed mode first order universal filter (FO-UF) has been proposed in this study. One Extra X Current Conveyor Transconductance Amplifier (EXCCTA), one capacitor and two resistors are used to design the filter. The main attributes of the filter include (i) electronic tunability (ii) ability to work in all four modes of operation (iii) cascadability (iv) availability of low pass (LP), high pass (HP) and all pass (AP) responses simultaneously. By incorporating the filter to design the second order current mode and trans-admittance mode filters, the filter's practicability is investigated. To determine how component spread and frequency-dependent current and voltage transfer gains affect the filter's operation, nonideal analysis is conducted. The layout of the EXCCTA occupies an area of 51.47*23.33µm 2 and it is designed and validated using 180nm GPDK in Cadence software. The FO-UF functions at ±1.25V supply at a frequency of 16.23MHz. Experimental analysis using off the shelf integrated circuits (ICs), the AD844 and CA3080 is also conducted to validate the proposed design.