Design of integrated all‐pass filters with linear group delay for analog signal processing applications

Abstract

This article describes the design of integrated linear group delay filters for analog signal processing (ASP) applications and their implementation through constant-resistance lattice and bridged-T networks. Unlike previously published works, our design method uses a recursive procedure as the basis for the synthesis of a suitable transfer function. Thanks to this method, filters with a more linear group delay characteristic and flat magnitude response can be obtained.Two filters are designed in a 0.13-μm BiCMOS technology to demonstrate the method: a balanced lattice with a negative slope and an unbalanced bridged-T of positive slope. KEYWORDS all-pass filter, bridged-T network, lattice network, linear group delay, time-bandwidth product Int J Circ Theor Appl. 2020;48:658-673. wileyonlinelibrary.com/journal/cta