Low noise wideband monotonically raising gain active equalizer in SiGe BiCMOS for phased arrays

Official URL: http://dx.doi.org/10.1109/MWSCAS48704.2020.9184565

In this brief, a wideband low noise active equalizer is presented that is implemented by utilizing SiGe BiCMOS technology, and packaged by in-house Au-stud bump flip-chip bonding. An amplification and filter stages are integrated to result in a gain profile, which is monotonically increasing over frequency. This is enabled by favouring a high cut-off frequency for the amplifier’s small-sized HBTs higher than the band of interest. Cascading the band select filter with the amplifier, enables the desired 50 Ω matching throughout 70 % of fractional bandwidth (BW). A Rogers 5870 substrate is utilized to flip the chip by in-house Au-stud bumps capability. A conductive epoxy is used for the bump and copper transition. The active equalizer achieves 10.83 dB peak gain with + 2.03 dB/BW of a linear slope between 5-to-13 GHz. Its measured noise figure is 3 dB at peak gain, after de-embedding the PCB transmission lines. The design's output compression point is –3.15 dBm while dissipating 46 mW of power in 1 mm 2 area. To the best of authors’ knowledge, the active equalizer has the highest gain-NF product and gain slope features among similar works.