Second Generation Controlled Current Conveyors (CCCII) and Their Applications - Current Conveyors: Variants, Applications and Hardware Implementations - page 272

I b2

I b1
Z+

I b3

Z−

Y Y

Y Z+

Z−

I 0LP

C 2

Z+

C 1

Z−

I in R 0 I 0BP

X Z+ X X Z−

Z−

I 0HP

Fig. 9.29 Current-controlled CM universal biquad proposed by Senani et al. (Adapted from [ 26 ]
©

2004 IEICE)

In the above expressions T 1 ¼ R x1 C 1 ;T 2 ¼ R x2 C 2 and K

R x3 /R x4 Thus, an attrac-
tive feature of this circuit is that no component-matching or realization constraints
have been encountered in case of notch and all pass filter realizations. Using bipolar
transistors PR100N and NP100N to realize a standard translinear CCCII with
multiple outputs, with DC bias voltages taken as 3 V, it has been possible to
design the circuit to realize various filters with f 0 of the order of 1 MHz and the
tunability of f 0 and Q 0 has been possible by changing the various DC bias currents
appropriately, typically in the range 10-300

¼

A.
A current-mode universal active filter with one input and multiple outputs was
proposed by Senani et al. [ 26 ] which is shown in Fig. 9.29 .
The three responses realized by this circuit are given by:

μ

H OBP ˉ Q 0 s
Ds

0

H OHP s 2
Ds

I 0 LP
I in ¼

H OLP ˉ I 0 BP

I in ¼

and I OHP

I in ¼

ð 9 : 35 Þ

ðÞ ;

Ds ðÞ ðÞ

where

R 0
R x 3

H OHP ¼ H OBP ¼ H OLP ¼ ð 9 : 36 Þ

and

1
R x 1 C 1 s

1
R x 1 R x 2 C 1 C 2

s 2

Ds ðÞ ¼ þ þ ð 9 : 37 Þ

V T

Using R xi ¼

2 I bi ; i

¼ 1 3, the parameters of the realized filters are found to be:

r

I b 1 I b 2
C 1 C 2

r

I b 2 C 1
I b 1 C 2

2
V T

; ˉ 0

2 I b 1
V T C 1 ;

ˉ 0 ¼

Q 0 ¼

Q 0 ¼ ;