Optimization Technique for High-Gain CMOS Power Amplifier for 5G Applications

In this study, a differential power amplifier (PA) with a high gain of over 30 dB by configuring a three-stage common source unit amplifier was designed. To ensure the stability of the high-gain differential PA, the analysis to apply the capacitive neutralization method to the differential common source PA was conducted. From the analysis, the required neutralized capacitance was quantitatively calculated from the estimated parasitic components of a power cell used in the PA. To verify the feasibility of the proposed optimization technique, a Ka-band PA was designed with a 65 nm RFCMOS process. The measurement results showed a gain of 30.7 dB. The saturated output power was measured as 16.1 dBm, maximum power-added efficiency (PAE) was 29.7%, and P1dB was 13.1 dBm.

Design and Hardware Implementation of an IGBT-Based Half-Bridge Cell for Modular Voltage Source Inverters

This article presents the design and hardware implementation of an IGBT-based half-bridge voltage source inverter (VSI) to be used as a basic cell to assemble VSIs of different topologies in modular ways. Herein, we have presented the design methodology and utilized techniques for reducing stray inductances and EMI radiation on the printed circuit board, as well as the way to calculate and select the main electronic components. For the design of the circuit board, local regulations for grid interconnection and international standards were considered in order to obtain a safe and reliable electronic power cell. The developed hardware was subjected to different tests using AC electric motors as loads to validate its design. Two VSIs topologies were evaluated: a single-phase two-level full-bridge inverter and a three-phase two-level inverter. The experimental results validated the theory and demonstrated the excellent performance, reliability, and high efficiency of the developed half-bridge power cell for modular VSIs.

Intrinsic Piezo-Nanogenerator Integrated Flexible Self-Charging Supercapacitor Power Cell: Overview and Outlook

Coupling of energy harvesting unit with the energy storage one has already gained considerable attention in the development of self-powered portable gadgets. Nanogenerators (NGs) and flexible supercapacitors (SCs), both are considered as leading energy devices in their respective domains. Integration with each other opens up the new possibility of self-charging supercapacitors. Among, the NGs piezo-electric NGs are preferred over triboelectric NGs for integration with SC to avoid additional circuit complexity. Here, device architecture, the working principle, and imperative parameters regarding piezo-electric NG-based self-powered SCs are sequentially discussed. Finally, a conclusion is drawn from some recent works, and remarks are provided for cultivating its overall performance.