Basic Analog Circuit Building Blocks Using CCs and Application of CCs in Impedance Synthesis - Current Conveyors: Variants, Applications and Hardware Implementations - page 112

R 1

C 2

CCII

I 1 C 1

CCII x

1

-

V 1

z

y

y

- z

x

R 2

I 2

2

V 2

R 3

Fig. 5.35 The first Ideal floating FDNR using only two CCs proposed by Senani [ 40 ] in 1984

Three distinctly different floating generalized positive immittance converter/
inverter (FGPIC/FGPII) circuits were proposed in [ 47 ] which are shown here in
Fig. 5.36a-c .
A straight forward analysis of these circuits assuming ideal CCII-s shows that
the impedance realized between ports one and two is given by (Z 1 Z 4 Z L /Z 2 Z 3 ). From
the generalized expression, it is obvious that all the three circuits can be used to
realize a variety of floating impedances using different choice of circuit
impedances.
When the circuits of Fig. 5.36a-c are re-analyzed by taking into account the
non-ideal h parameters of the CCII-s, it is found that the resulting Y-parameters of
the circuits of Fig. 5.36a, b are more complex and unsymmetrical than those of
circuit of Fig. 5.36c which after considering only the non-ideal current gains
between ports X and Z of the two CCII-s, namely, h 32A and h 32B of the two CCII-
s are found to be:

Y 1 Y 4 Y L
Y 2 Y 3

Y 11 ¼ h 32 A þ Y 1 1 ð h 32 A Þ ¼ Y 12 ð 5 : 45 Þ

þ

1
h 32 B

Y 1 Y 4 Y L
Y 2 Y 3

1
h 32 B

Y 4
Y 2

Y 21 ¼ Y 1 1 ¼ Y 22 ð 5 : 46 Þ

The above expressions clearly show that, other than the desirable first part,
the equivalent circuit of the realized impedance will contain unwanted parasitic
elements. Nevertheless, the fact that these circuits can be successfully used in the
design of filters has been demonstrated in [ 61 ] even though the CCII

was realized

therein by Huertas op-amp-based CC-implementation (see reference [4] of

'

Chap. 2 ).
For other two CC-based lossy FI simulators, the interested readers may refer to
[ 18 , 84 ].