A 3.3 volt electronically tunable active filter usable to beyond 1 GHz

Abstract

A very high frequency low voltage active filter is proposed which is based on the "log filters" introduced by Frey (1993). These filters have been shown to be a special case of exponential state space filters. Log filters are particularly well suited for high frequency applications since they are essentially current mode networks. They are also well suited to low power supply operation, not only because of their current-mode nature, but also because there is no overhead associated with linearization, since the intrinsic nonlinearity is an integral part of the design formulation. In this paper it is shown that log filter topologies are possible which function well at 3.3 volts.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>