Basic Analog Circuit Building Blocks Using CCs and Application of CCs in Impedance Synthesis - Current Conveyors: Variants, Applications and Hardware Implementations - page 120

R 2

1

C

1

R 1

L = CR 1 R 2

R P = R 2

1

R 2

R P = R 2

C

1

L = CR 1 R 2

R 1

Fig. 5.45 Nullors model employed for synthesizing CCII based floating impedance configura-
tions [ 56 ]

RL impedance respectively. From these models, the nullor models of floating
impedances can be obtained by ungrounding all the passive elements, nullators
and norators. From these FI models, two additional FI models can be obtained by
swapping nullators by norators and vice versa. Lastly, four additional nullor models
can be evolved by carrying out the operation of port-transposition on the preceding
four models. This operation, however, will change the nature of impedances
simulated in the sense that if the original model represented a floating series RL
the transposed model will represent a floating parallel RL and vice versa.
The actual CCII based circuits emanating from the above described eight

nullor models turn out to be as shown in Fig. 5.46 . It can be verified that the circuits
of Fig. 5.46a, c, f, and g have the Y matrix given by:

1

1
R 2 þ

1
sCR 1 R 2

1

½ ¼ Y ð 5 : 49 Þ

11

Hence, all these circuits realize a floating parallel RL impedance with

L ¼ CR 1 R 2 ; R p ¼ R 2 ð 5 : 50 Þ

On the other hand, the circuit configurations of Fig. 5.46b, d, e and h are charac-
terized by the Y- matrix:

1

1 1

½ ¼ Y ð 5 : 51 Þ

ð R 2 þ sCR 1 R 2 Þ 11