Hardware Reference
In-Depth Information
CCII
3
CCII
2
CCII
1
Z
3
-
Z
3
-
Y
3
X
3
Y
2
X
2
Z
2
-
Z
2
-
Z
1
+
Z
1
-
Y
1
X
1
i
in
i
01
B
A
i
03
i
02
C
2
C
1
R
1
R
2
R
3
Fig. 12.48 The configuration for realizing CM universal biquad and dual-mode Quadrature
oscillator proposed by Abdalla et al. [
127
]
R
1
C
2
Ds
1
s
2
1
C
1
C
2
R
2
R
1
s
þ
1
C
1
C
2
R
2
R
1
Ds
i
01
i
in
¼
i
02
i
in
¼
i
03
i
in
¼
ð
12
:
170
Þ
ðÞ
;
ðÞ
;
Ds
ðÞ
n
C
2
R
1
o
þ
1
C
1
C
2
R
2
R
1
s
2
1
s
s
2
Ds
ð
i
02
þ
i
03
Þ
¼
ð
i
01
þ
Þ
i
in
¼
i
03
ð
12
:
171
Þ
ðÞ
;
i
in
Ds
ðÞ
where
1
C
2
R
3
þ
1
C
1
C
2
R
2
R
1
s
2
Ds
ðÞ¼
þ
s
ð
12
:
172
Þ
(ii)
CM/VM quadrature single resistance controlled oscillator (SRCO):
0 and getting
another Z
1
+ output terminal from CCII
1
and connecting the same to node (C). Thus,
the output voltages in VM are considered to be the voltage at node (B) equal to v
01
and voltage at node (A) equal to V
02
whereas the output currents in CM are
considered to be (i
01
) and (i
02
). A routine circuit analysis of this structure yields
the following characteristic equation (CE) (for both CM and VM quadrature
SRCOs)
The circuit shown in Fig.
12.48
can be modified by making
¼
1
C
2
1
R
3
1
R
1
1
C
1
C
2
R
2
R
1
¼
s
2
CE
þ
s
þ
0
ð
12
:
173
Þ
:
From the above CE, the condition of oscillation and frequency of oscillation are
found to be:
s
1
C
1
R
1
C
2
R
2
1
2
CO
R
1
R
3
and FO
ð
12
:
174
Þ
:
:
ˀ
Therefore, it is seen that both CO and FO are independently controllable by two
different resistors the former by R
1
and the latter by R
2
.
Search WWH ::
Custom Search