P. Wambacq et al., SYMBOLIC ANALYSIS OF LARGE ANALOG CIRCUITS USING A SENSITIVITY-DRIVENENUMERATION OF COMMON SPANNING-TREES, IEEE transactions on circuits and systems. 2, Analog and digital signal processing, 45(10), 1998, pp. 1342-1350
A new approach for the generation of approximate symbolic network func
tions is presented. This approach is used to analyze large analog inte
grated circuits. It is based on a matroid intersection algorithm that
directly enumerates common spanning trees of a two-graph representatio
n of a given circuit. The approximation algorithm is based on an inspe
ction of the sensitivity of the magnitude of a network function with r
espect to the different coefficients of a network function. These sens
itivities as a function of frequency control the enumeration process.
In this way, the algorithm enumerates a minimum number of the dominant
terms for each coefficient of the network function. The complete algo
rithm runs in O(k mn(3)) time, in which K is the average number of mat
roid intersections that must be generated for the approximation of eac
h coefficient of the network function, n is the number of nodes in the
linearized network and m the number of circuit elements, At the end o
f the paper experimental results are presented. These results indicate
that this new approach is superior to other approaches to generate an
approximate symbolic network function from a given two-graph.