Second Generation Controlled Current Conveyors (CCCII) and Their Applications - Current Conveyors: Variants, Applications and Hardware Implementations - page 248

Chapter 9
Second Generation Controlled Current
Conveyors (CCCII) and Their Applications

Abstract An interesting method of realizing electronically-controllable functions
is through the use of the translinear current conveyor which is implemented from a
mixed translinear cell (MTC). This implementation exhibits an input resistance
looking into terminal X which is electronically-controllable and hence, it is referred
to as the Second generation Controlled Current Conveyor (CCCII). The objective of
this chapter is to present significant developments on the hardware implementation
and applications of electronically-controllable analog circuits using CCCIIs as
active elements.

9.1 Introduction

Operational-transconductance-amplifier-capacitor (OTA-C) circuits have been the
popular choice for synthesizing electronically-controllable universal voltage mode
and current-mode biquads, sinusoidal oscillators as well as relaxation oscillators
capable of generating non-sinusoidal signals such as square wave,

triangular

wave etc.
With the advent of the second generation controlled current conveyors (CCCII)
[ 1 - 132 ] which provide electronic control of the X-port input resistance R x through
an external bias current, CCCIIs have attracted lot of attention of researchers and
circuit designers around the world as alternative building blocks to synthesize a
variety of electronically-controllable signal processing and signal generation cir-
cuits. The electronic-controllability in a CCCII emanates from a specific circuit
architecture known as a mixed translinear cell (MTC) which forms the input cell of
a typical CCII architecture. This MTC, apart from the electronic-control, also
empowers the CCCIIs with higher slew rate and larger input signal handling
capability. The above mentioned features have been the primary reasons for
stimulating a lot of research on the use of CCCIIs in the synthesis of a variety of
linear as well as non-linear analog signal processing circuits, for instance, see [ 1 , 2 ]
and the references cited therein.
This chapter focuses on the synthesis of various electronically-controllable
signal processing/signal generation circuits such as simulated impedances,