Hardware Reference
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I in2
I in3
I in1
CCII
CCII
CCII
z+
y
x
y
x
y
x
y
x
R 3
z−
z−
z−
C 2
V in3
R 4
C 1
R1
CCII
V in1
V in2
I 0
z+
y
x
V out
z+
R 5
R 6
R 7
R 2
V in4
Fig. 12.53 Mixed-mode CCII-based configuration proposed by Abuelma ' atti and Bentrcia [ 134 ]
V in 4
C 1 R 6 þ
V in 2
C 1 R 5
V in 1
C 1 C 2 R 1 R 5
s 2 V in 3
N r s
ðÞ¼
s
þ
þ
ð
12
:
190
Þ
I in 2
C 1
I in 1
C 1 C 2 R 5
s 2 R 3 I in 3
þ
s
and
s 2 C 1 C 2 R 1 R 3 R 5 R 6 þ
D r s
ðÞ¼
sC 2 R 1 R 4 R 5 þ
R 4 R 6
ð
12
:
191
Þ
From equations ( 12.189 ) and ( 12.190 ), various inverting and non-inverting mixed-
mode responses in both VM and CM can be obtained as:
(a) Realization of VM filter responses ( I in 1 ¼
I in 2 ¼
I in 3 ¼
0):
HPF: V in 1 ¼
V in 2 ¼
V in 4 ¼
0, V in 3 ¼
V in ; LPF: V in 3 ¼
V in 2 ¼
V in 4 ¼
0, V in 1 ¼
V in
BPF: V in 1 ¼
V in 2 ¼
V in 3 ¼
0, V in 4 ¼
V in or V in 1 ¼
V in 3 ¼
V in 4 ¼
0, V in 2 ¼
V in
Notch: V in 1 ¼
V in 3 ¼
V in
and V in 2 ¼
V in 4 ¼
0 with R 1 ¼
R 4
and APF:
V in 1 ¼
V in 3 ¼
V in 4 ¼
V in , V in 2 ¼
0 and R 3 ¼
R 4 ;or V in 1 ¼
V in 2 ¼
V in 3 ¼
V in , V in 4 ¼
0
and R 3 ¼
R 6 .
In the above cases, the polarities are referred to the VM outputs, the mixed mode
outputs can be obtained with reverse polarities.
R 4 , R 5 ¼
(b) Realization of CM filter responses ( V in 1 ¼
V in 2 ¼
V in 3 ¼
V in 4 ¼
0):
BPF: I in 1 ¼
I in 3 ¼
0, I in 2 ¼
I in ; LPF: I in 2 ¼
I in 3 ¼
0, I in 1 ¼
I in HPF: I in 1 ¼
I in 2 ¼
0,
I in 3 ¼
I in ; Notch:
I in 2 ¼
0, I in 3 ¼
I in ¼
I in 1 and APF:
I in 2 ¼
I in 3 ¼
I in ¼
I in 1 and
R 1 ¼
R 6 .
By appropriate selection(s) of input(s), the other modes namely, transimpedance
and transconductance filter responses can also be realized.
The filter parameters
R 4 ¼
ˉ 0 and (
ˉ 0 /Q 0 ) can be given by:
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