First, Second and Higher Order Filter Design Using Current Conveyors - Current Conveyors: Variants, Applications and Hardware Implementations - page 161

Fig. 6.29 Senani ' s
Universal CM biquad
derived through the
proposed methodology [ 24 ]

CCIb−

I R0

y
x

z

R 0

CCII−
x
y

CCI−

I C0

y

z

z

x

I in

C 0

CCI−

I L0

y

z

x

CCII−

y

y

z

CCII+

C 1

z

x

x

R 1

R 2

Fig. 6.30 Senani sCM

biquad realizable with only
four CCIIs [ 24 ]

' R 1

CCII-

I 02

x

z

y

CCII-

I 01

x
y

z

C 1

I in

CCII-

y

z

x

C 2

R 2

I 03

x

z

y

CCII+

controlled resistors) (ii) easy conversion into a VM biquad and (iii) suitability for
IC implementation. Assuming ideal CCs, a routine circuit analysis yields the
following current transfer functions:

R 1 C 1
Ds

1

s

1
C 1 C 2 R 1 R 2
Ds

s 2
Ds

I 01
I in ¼

I 02
I in ¼

I 03
I in ¼ ðÞ ;

;

ðÞ ðÞ

R 3
C 1 R 1 R 4 þ

1
C 1 C 2 R 1 R 2

s 2

where Ds ðÞ ¼ þ s ð 6 : 43 Þ