Analog Filter Design Revisited: Circuit Configurations Using Newer Varieties of CCs - Current Conveyors: Variants, Applications and Hardware Implementations - page 428

Horng ' s nth order transfer function realization using analytical synthesis
approach Horng in [ 138 ] presented two circuit configurations to realize general
high-order voltage and current transfer functions using CCIIs which are based on an
analytical synthesis method. General nth-order VM transfer function needs (2n + 1)
CCIIs, (2n + 2) grounded resistors and n number of grounded capacitors. This
method can also be applied to the synthesis of CM transfer functions. To implement
general nth-order CM transfer function, (2n + 2) CCIIs, (2n + 2) grounded resistors
and n grounded capacitors are required. To confirm the validity of synthesis
methods, VM 3rd order APF, LPF and HPF and CM notch, LPF and HPF functions
have been derived.
The proposed analytical synthesis method is based on the analytical decompo-
sition of a single general nth-order VM function into n first-order integrator
functions and one summer function produced following the applications of manip-
ulations of algebraic operations. The active elements used for the synthesis of
general high-order VM/CM transfer function configurations are the multi-output
CCIIs. For the details of the various steps of the proposed methodology and the
resulting circuit implementations, the reader is referred to [ 138 ].
Concluding Remarks
In Chap. 6 we have presented a number of filter configurations using the basic
CCs. By contrast, in this chapter we focused on numerous other filter config-
urations using different variants of CCs which however, are not available
commercially as off-the-shelf ICs. From the spectrum of circuits presented in
this chapter, it is, however, clear that the configurations using the considered
variants of CCs do offer a number of advantageous features over those
structures which are realized with conventional CCs.
In view of the above, therefore, these structures although not
implementable in discrete designs (except at the cost of employing more
number of commercially available IC CCs) but still are potential candidates
for integrating analog filters along with digital circuits as part of a complete
system on the chip. In addition, the material presented in this chapter together
with that to be presented in Chaps. 13 , 14 and 15 , may also be a good
motivation for IC designers to come up with stand-alone ICs of the modified
CCs considered here and in the quoted chapters.
References
1. Hassan TM, Mahmoud SA (2010) New CMOS DVCC realization and applications to
instrumentation amplifier and active-RC filters. Int J Electron Commun (AEU) 64:47-55
2. Yuce E (2009) Voltage-mode multifunction filters employing a single DVCC and grounded
capacitors. IEEE Trans Instrum Meas 58:2216-2221
3. Minaei S, Yuce E (2010) Novel voltage-mode all-pass filter based on using DVCCs. Circ Syst
Sig Process 29:391-402