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Fig. 2.9 Modified version
of Senani ' s implementation
of CC proposed by
Papazoglou and Karybakas
[ 15 ]
Y
+
+
X
g m
Z
R 0
I BIAS
+
R 1
V c
R 2
Fig. 2.10 CC realization
proposed by Karybakas
et al. [ 12 ]
Y
+
Z
I B2
G 2
+−
X
+−
R 0
G 1
I B1
non-linear phenomenon (owing to OTA input current and CMRR effects) do not
affect the circuit performance.
2.2.8 Wilson
s OMA-Based Implementations of CCII+/
'
It was demonstrated by Wilson [ 7 ] that wide band precision current conveyor can
be obtained by adopting the so called power supply current sensing technique
whose embodiment is also popularly referred to as an Operational Mirrored Ampli-
fier (OMA). An OMA-based CC implementation using two complementary mod-
ified Wilson current mirrors connected between the DC bias terminals and power
supply rails to realize a CCII+ is shown in Fig. 2.11 . It is well known that the output
current of the op-amp in the internally compensated type op-amps such as LF356/
ʼ
A741 is equal to the difference of the two power supply currents I p and I N as shown
in Fig. 2.11 . Thus, x-terminal input current manifests itself as the difference
between I p and I n each of which are copied by the current mirrors and their
difference is made available at the high output impedance terminal Z thereby
realizing I z ¼
I x . Since the op-amp with a unity negative feedback ensures equality
of the voltages at Y and X terminals leading to V x ¼
V y and the ideally infinite input
impedance of the op-amp makes I y ¼
0, it follows that the circuit realizes a CCII+.
 
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