A 50MHz–16GHz low distortion SOI voltage controlled attenuator IC with IIP3 > +38dBm and control range of > 25dB

This paper discusses a 50MHz–16GHz wideband, low distortion, voltage controlled attenuator (VCA) on silicon on insulator (SOI) CMOS technology. The VCA design is based on passive FET absorptive attenuator structures but uses stacked FET techniques to dramatically improve the distortion characteristics and signal handling capability. It leverages a surface mount compatible flip chip IC in an over molded laminate package to minimize parasitics. The VCA achieves >25dB attenuation range, IIP3 of > +38dBm and IP1dB > 25dBm up to 16GHz. The laminate and flip chip combination maintains a return loss of better than −8dB over the entire frequency and attenuation range. The insertion loss at 16GHz is 5.0dB at minimum attenuation.