A 137-GHz Ultra-Wide Bandwidth High-Linearity CMOS Distributed Amplifier for High-Speed Communication

This paper presents a 137-GHz bandwidth highlinearity CMOS distributed amplifier (DA) for ultra-wide bandwidth power amplification applications. Utilizing intrastack coupling and input-output transmission lines (TLs), the proposed DA achieves ultra-wide bandwidth and improved linearity. Folding the input and output TLs enables efficient transformer implementation without the need for additional large areas. Furthermore, the frequency-dependent coupling between the input and output TLs increases bandwidth up to 137 GHz. Each common source (CS) stage is capacitively coupled to the input TLs, allowing for different mode operations and enhancing linearity. The proposed CMOS DA boasts the widest bandwidth of 137-GHz among reported CMOS DAs, along with 16.5/15.2 dBm peak $\mathrm{P}_{\mathrm{s}\mathrm{a}\mathrm{t}}/$PidB and 15.1% peak PAE at 26 GHz. The proposed CMOS DA also achieves 505.9 GHz, $\mathrm{P}_{\mathrm{s}\mathrm{a}\mathrm{t}}\times \mathrm{B}\mathrm{W}\times \mathrm{P}\mathrm{A}\mathrm{E}/\mathrm{P}_{\mathrm{D}\mathrm{C}}$ figure-of-merit (FoM). To the best of our knowledge, our proposed CMOS DA achieves the highest FoM.