An Inductive-bounce Enhanced Output-pad for CMOS UltraWideBand RF Applications

Resonant pad designs that tunes out parasitic pad capacitances is a difficult task in broadband wireless RF applications. This paper reports a novel CMOS output pad design using inductive ground bounce which is found to be suitable for UltraWideBand RF applications. As pad parasitic capacitances as small as 0.35pF becomes a significant ground leakage path for the UltraWideBand frequency range of 3.1GHz-10.6GHz, inductive bounces from inductors as small as 1-2 nH can provide substantial impedance against this leakage. Simulations using the 0.18μm TSMC process parameters indicate considerable output pad performance improvement when inductive bounce is used. Also, s- parameter simulations verify the results obtained.