Second Generation Miscellaneous Linear/Nonlinear Applications of Various Types of Current Conveyors - Current Conveyors: Variants, Applications and Hardware Implementations - page 510

Fig. 15.17 CCII-based
MDAC proposed by Hwang
et al. (Adapted from [ 19 ] ©
2007 Springer Science
+ Business Media)

C 3

V out

∅ 2

∅ 1

C 1 ∅ 1

x

∅ 2

z

V in

∅ 1 ∅ 1 y

C 2

∅ 2 ∅ 1

V R

15.9 CCII-Based Digital-to-Analog Converter

A FBCCII-based multiplying digital-to-analog converter (MDAC) due to Hwang
et al. [ 19 ] is shown here in Fig. 15.17 . Its operation can be explained as follows.
When the clock pulse

ˆ 1 is HIGH, both the capacitors C 1 and C 2 sample the input
V in and both the capacitors are connected in series and to ground. In the next phase,
when ˆ 2 is HIGH the bottom plate of the capacitor C 2 gets connected to the voltage

V R. The two capacitors are still connected in series but the top plate of the capacitor
C 1 is now connected to Y-terminal of the CCII. The output of the circuit is given by

V out ¼ V R þ 2 V in ð 15 : 64 Þ

The output of the circuit is determined by noting that I z and I x are equal to make the
output voltage settle faster while the feedback capacitor C 3 plays a major role in
reducing high frequency and switching noises. For V R ¼ 0, the input/output behav-

ior of the circuit is shown in Fig. 15.17 , where V in is the sine wave of 1 V p-p at
2 MHz frequency and the square wave signal (with an amplification by a factor of
two) is the output waveform.

15.10 Chaos Generators: Revisited

There have been numerous attempts in making chaotic oscillators using CCs as well
as numerous other building blocks as is evident from a large amount of literature in
this area, for instance see [ 21 , 22 , 23 ] and the references cited therein. Gandhi [ 24 ]
presented a DOCCII based implementation which nearly follows the same meth-
odology as adopted in the CFOA-based circuit proposed by Senani and Gupta
earlier in [ 25 ]. Gandhi s

diode made from two DOCCII is nearly analogist to the two CFOA based imple-
mentation proposed in [ 25 ] while the simulated inductor with the inductive current

s preposition is shown in Fig. 15.18 where the Chua

' '