Distributed amplifiers with non-uniform filtering structures

This paper presents a new design concept to better control both passband and stop-band characteristics of distributed amplifiers (DAs) by using non-uniform filtering structures instead of conventional constant-k sections. Two circuit prototypes with Butterworth and Chebyshev filtering were designed using network synthesis method, and implemented in a 0.18 mu m digital CMOS technology. The Butterworth prototype achieved 11.7dB gain, 9GHz bandwidth, and -5.dB/GHz roll-off. The Chebyshev one achieved 10dB gain, 8.5GHz bandwidth and -8dB/GHz roll-off.