ISSN 10637397, Russian Microelectronics, 2014, Vol. 43, No. 7, pp. 505–510. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © D.P. Frolov, 2013, published in Izvestiya Vysshikh Uchebnykh Zavedenii. Elektronika, 2013, No. 5(103), pp. 45–51.
There are different approaches to constructing
reconfigurable analogdigital array chips (ADACs).
The arrays are constructed using computing units and
floatinggate transistors . There are arrays that are
reconfigured by a laser  or tuned by a layer of con
tact vias , as well as different modifications of elec
tricallyreconfigurable analog arrays .
In the general case, ADAC involves the config
urable structure of analog elements (cells). A funda
mental element of the methods for constructing
reconfigurable structures is the interconnection array,
i.e., the circuit for commutating cells against each
other and with IC terminals. When designing a recon
figurable array structure using the above methods, the
problem of choosing an optimal composition of the
cell and minimizing the number of interconnections
arises. The array must satisfy the following two condi
tions: it must be a basis for constructing most typical
analog devices and possess the characteristics of accu
rately processing analog signals.
In this work, an approach to constructing a univer
sal reconfigurable analog cell (RA cell) for applying in
analogdigital array structures with the use of the mor
phosynthesis method  is proposed.
2. METHOD FOR SYNTHESIZING
THE STRUCTURE OF THE RA CELL
AND ESTIMATING ITS EFFICIENCY
According to the subcircuit idealization concept
, an arbitrary analog device can be implemented
using the composition of analog etalons and basic ana
log functions (BAFs). There are five BAFs (amplifica
tion, comparison, multiplication, frequency filtration,
and restriction) that form the functionally complete
set of analog operations. The elements implementing
the amplification and comparison BAFs are the most
The RA cell that provides the simultaneous imple
mentation of the amplification and comparison is pro
posed. For this purpose, a graph of the ordered morpho
logical set of the main classification features of opera
tional amplifiers (opamps) and comparators is
constructed based on analyzing the classification of the
circuits of the latter (Fig. 1).
The analysis of the morphological graph uniquely
identifies the set of objects (amplification and com
parison circuits) of the following implementable func
tional elements (FEs): FE1 is the differential current
output opamp; FE2 is the differential voltageoutput
opamp; FE3 is the voltage comparator; FE4 is the fully
differential currentoutput opamp; FE5 is the fully
differential voltageoutput opamp; FE6 is the gated
voltage comparator; and FE7 is the fully differential
The identified FE set is necessary and sufficient for
implementing most typical analog devices provided
that additional passive components are used. When
Morphosynthesis Method forDesigning the Reconfigurable Analog
Cell of a Semicustom AnalogDigital VLSIC with an Array Structure
D. P. Frolov
National Research University of Electronic Technology (MIET), Moscow, Russia
Received March 25, 2013
—Approaches to constructing analog reconfigurable cells of integrated circuits with an array struc
ture are discussed. A morphological method for synthesizing an analog reconfigurable cell and the criteria for
estimating its efficiency are proposed. The design and electric circuit of the reconfigurable cell are developed
and the results of circuit simulation are presented.
Morphological graph of the main classification fea
tures of opamps and comparators.