Frequency Response of Electronically Tunable Current-Mode Third Order High Pass and Low Pass Filter for Q = 10

Dr D D Mulajkar

doi:10.47191/ijcsrr/v4-i10-23

Abstract

The circuits using current-mode (CM) building blocks have received considerable attention in many filtering and signal processing applications. Compared to their voltage-mode(VM) counterparts, the current-mode building blocks are attractive because of their wider bandwidth, higher slew rate, and lower power consumptions. In IC technology, it is desirable to operate circuits at low voltages which can be achieved by using CM building blocks. As a large number of op-amp based circuits with elegant realization procedures are already available, it is worthwhile to convert them into the circuits based on current-mode building blocks. In this paper, a realization of a current mode third order high pass and low pass filter is described. The proposed circuit employs operational amplifier as the basic building unit. The filter circuit realizes quadratic work function. It provides electronically tuning capability of the filter characteristics. The proposed circuit works ideal for Center frequency fo= 10 k and Circuit merit factor Q > 1. The gain roll-off this configuration is 18dB/octave. The circuit is suitable for monolithic integration and high frequency operation. The filters developed were successful in obtaining passive sensitivities less than unity in magnitude and active sensitivities are half in magnitude, which is a noteworthy achievement. The circuit is suitable for high frequency operation and monolithic integration.

Highlights

At present, there is a growing interest in designing capacitor-less, resistor-less current mode active only filters using only active elements such as Operational amplifier [OA], Operational trans conductance amplifiers [OTAs]
Current mode filters have many advantages compared with their voltage mode counterparts
Many circuits for realizing voltage mode filters have been proposed by researchers

Summary

INTRODUCTION

There is a growing interest in designing capacitor-less, resistor-less current mode active only filters using only active elements such as Operational amplifier [OA], Operational trans conductance amplifiers [OTAs]. Many circuits for realizing voltage mode filters have been proposed by researchers. The realization of current mode transfer function is topic of considerable interest for researchers. Extensive work has been done employing active devices such as OAs and OTAs [2, 3]. Due to their many advantages there is growing interest in designing and implementing current mode active filters using second generation current conveyors [CCIIs]. Current mode active filters are designed with second generation duel output current conveyors [DO-CCII] [10]. This paper focuses on third order current mode active-R filter with quadratic transfer function.

CIRCUIT CONFIGURATION AND ANALYTICAL TREATMENT

AND DISCUSSION

CONCLUSION