A Broadband D-Band Dual-Peak Gmax-Core Amplifier With a T-Shaped Embedding Network in CMOS

We present a novel high-gain broadband <inline-formula> <tex-math notation="LaTeX">$G_{\mathrm {max}}$ </tex-math></inline-formula>-core amplifier with a T-shaped passive embedding network consisting of two series capacitors and one shunt inductor. The proposed <inline-formula> <tex-math notation="LaTeX">$G_{\mathrm {max}}$ </tex-math></inline-formula>-core has dual-peak properties. By staggering dual-peak <inline-formula> <tex-math notation="LaTeX">$G_{\mathrm {max}}$ </tex-math></inline-formula>-cores, a broad gain–bandwidth amplifier can be achieved with a small number of stages. In addition, the three elements of the T-shaped network give us a high degree of freedom in design. One can design not only the gain profile of the core but also the input and output impedance as desired with the embedding network. In this article, the proposed <inline-formula> <tex-math notation="LaTeX">$G_{\mathrm {max}}$ </tex-math></inline-formula>-core is theoretically analyzed. A three-stage D-band dual-peak <inline-formula> <tex-math notation="LaTeX">$G_{\mathrm {max}}$ </tex-math></inline-formula>-core amplifier is implemented in a 28-nm FDSOI CMOS process to demonstrate the idea. The fabricated amplifier offers a peak small-signal gain and bandwidth of 14.5 dB and 26 GHz (117–143 GHz), respectively, with the power consumption of 21.6 mW. This work shows a reasonable gain–bandwidth product per power dissipation among state-of-the-art amplifiers operating at similar frequencies.