A Grounded Capacitor Differentiator Using Current Feedback Amplifier

Jiun-Wei Horng,Guang-Ting Huang

doi:10.4236/cs.2013.42031

Abstract

A new non-inverting RC active differentiator network base on a current feedback amplifier and using a grounded capacitor is described. Small time constant can be achieved by adjusting a single grounded resistor. Because the output impedance of the CFA is very low, the output terminal of the proposed circuit can be directly connected to the next stage. Experimental results that confirm theoretical analysis are presented.

Highlights

Active RC differentiator networks are useful for a number of applications in the areas of electronic signal processing or signal conditioning [1,2,3,4,5,6,7,8,9,10]
Several RC differentiator networks based on conventional operational amplifiers (Op Amps) were proposed [1,2,3,4,5]
The Current feedback amplifiers (CFAs) is equivalent to second-generation current conveyor (CCII) with a voltage buffer [11]

Summary

Introduction

Active RC differentiator networks are useful for a number of applications in the areas of electronic signal processing or signal conditioning [1,2,3,4,5,6,7,8,9,10]. Patranabis and Ghosh [6] proposed a generic configuration for realizing integrators and differentiators by using one CCII, one grounded capacitor and some resistors. Liu and Hwang [7] proposed five generic configurations for realizing dual-input differentiators using two CCIIs. the time constants of the differentiators presented in Figure 1 of [6] cannot be independently adjusted by grounded resistor. Dual-input differentiator circuit by using one plus-type CFA, one minus-type CFA, five resistors and one floating capacitor. In 2001, Lee and Liu [9] proposed a differentiator circuit by using one minus-type CFA, five resistors and one floating capacitor. A new differentiator network by using one plus-type CFA, five resistors and one grounded capacitor is presented. The proposed circuit uses only one plus-type CFA that is simpler than the minus-type CFAs in [8,9]

Circuit Description

Non-Ideal Effects

Experimental Results

Conclusion