Analog Filter Design Revisited: Circuit Configurations Using Newer Varieties of CCs - Current Conveyors: Variants, Applications and Hardware Implementations - page 416

I in

z+

y

R 3 z+

y

I 02

z−

2

I 01 C 2

1

C 1

z+

x

z+

x

R 1

R 4

I 03

y

z+

3

x z+

R 2

Fig. 12.47 New SIMO-type universal CM biquad proposed by Senani et al. [ 126 ]

s 2 C 1 R 1 C 2 R 2 þ Ds ðÞ¼ sC 2 R 2 þ 1 ð 12 : 168 Þ

The various filter parameters of the realized filter can be given by:

r

1
C 1 C 2 R 1 R 2

1
C 1 R 1 ;

R 3
R 4

ω 0 ¼ BW ¼ H 0 ¼ ð 12 : 169 Þ

;

Thus, it is seen that all the three filter parameters are tunable through separate
grounded resistors. The workability of all filter responses in Fig. 12.47 was con-
firmed by PSPICE simulations for f 0 ¼

1MHz,Q 0 ¼ 0.707 and H 0 ¼ 10. The

component values used were R 1 ¼ R 2 ¼

ʩ

,R 3 ¼

ʩ

,R 4 ¼

ʩ

7k 10 k 1k ,

C 1 ¼ 0.0159 nF and C 2 ¼ 0.0319 nF.

Abdalla-Bhaskar-Senani biquad A configuration for realising a CM universal
filter and dual-mode quadrature single resistor controlled oscillator was proposed
by Abdalla et al. in [ 127 ] which employs three dual output CCs (DOCCII) with five
grounded passive elements is shown in Fig. 12.48 . The circuit is capable to realize
all the five basic filter functions without requiring any component matching
alongwith tunability of filter parameters through grounded resistors.
With appropriate modification, the structure can also be converted into a quad-
rature oscillator which can give two VM outputs and as well as two CM outputs in
quadrature. The two modes of opration for Fig. 12.48 are:

(i) CM SIMO-type filter : The various filter functions realized by the configuration
are given as: