Title
Modelling The Dynamics Of Log-Domain Circuits
Abstract
Log-domain filters are an intriguing form of externally linear, internally nonlinear current-mode circuits, in which a compression stage is first used to convert the input currents to the logarithmic domain, then analogue processing is carried out on the resulting voltages, and finally input-output linearity is restored by mapping the output voltages to current form through an expansion stage. The compressing and expanding operations confer on log-domain filters a number of desirable features, but they may be responsible for the loss of external linearity. In this paper, sufficient conditions for the external linearity of log-domain LC-ladders are established, and the local nature of this external linearity is highlighted. Certain log-domain LC-ladders employing floating capacitors may exhibit externally nonlinear behaviour even for zero input and very small initial conditions. We show how transistor parasitic capacitances are central to the emergence of this behaviour, and must be incorporated in the circuit model. Copyright (c) 2006 John Wiley & Sons, Ltd.
Year
DOI
Venue
2007
10.1002/cta.379
INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS
Keywords
Field
DocType
external linearity, log-domain circuits, nonlinear dynamics
Nonlinear system,Capacitor,Control theory,Linearity,Voltage,Electronic engineering,Logarithm,Electronic circuit,Transistor,Analog signal processing,Mathematics
Journal
Volume
Issue
ISSN
35
1
0098-9886
Citations 
PageRank 
References 
7
0.91
2
Authors
3
Name
Order
Citations
PageRank
Alon Ascoli126937.82
Paul Curran271.59
Orla Feely39025.65