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A high efficiency digital MMIC amplifier for mobile communication switch-mode concepts was designed by utilizing a 0.25 μm GaN HEMT technology with fT of 32 GHz. A comparative investigation of two different driver concepts for a 1.2 mm GaN HEMT PA is shown. The MMICs were on-wafer evaluated for class-D and class-S operation. A drain efficiency of 70% for an(More)
For the development of next-generation AlGaN/GaN based high electron mobility transistors (HEMTs) in industry, reliable software tools for DC and AC simulation are required. Our device simulator Minimos-NT was calibrated against experimental data for this purpose. Subsequently, AC and DC simulations for both scaled devices from the same generation and new(More)
In this paper, an extended version of the continuous class-<i>F</i><sup>-1</sup> mode power amplifier (PA) design approach is presented. A new formulation describing the current waveform in terms of just two additional parameters, while maintaining a constant half-wave rectified sinusoidal voltage waveform, allows multiple solutions of fundamental and(More)
Wide bandgap, high saturation velocity, and high thermal stability are some of the properties of GaN, which make it an excellent material for high-power, high frequency, and high temperature applications. Given the predicted wide-spread use, reliable models are needed for simulationbased optimization. As several application areas require the devices to(More)
A new concept for the low-frequency dispersion aspect of large-signal modeling of microwave III-V field-effect transistors is presented. The approach circumvents the integrability problem between the small-signal transconductance <i>Gm</i>RF and the output conductance <i>G</i><sub>dsRF</sub> by means of an integral formulation and simultaneously yields a(More)
In this paper, we present a fully-scalable compact small-signal equivalent circuit model for AlGaN/GaN HEMTs with a gate length of 100 nm. The compact model yields a parasitic shell topology and is scalable from two up to eight transistor-fingers and is valid for finger lengths from 15 &#x03BC;m to 100 &#x03BC;m. It accurately covers the frequency range(More)
AlGaN/GaN HEMTs have been widely used in RF power circuits such as high power amplifiers [1]. This is mainly due to the capability to handle large power. Besides this main advantage, this technology demonstrates good performances in terms of noise, linearity, and robustness. This paper presents the design, and measurement results of different mixers(More)
This work reports the development and fabrication of large area AlGaN/GaN-on-Si HFETs for the use in highly-efficient fast-switching power converters. High performance is demonstrated by full characterization of static- and dynamic-parameters and a direct comparison to two commercial state-of-the-art silicon power devices. Compared to their silicon(More)
The high power capabilities in combination with the low noise performance of Gallium Nitride (GaN) makes this technology an excellent choice for robust receivers. This paper presents the design and measured results of three different LNAs, which operate in C-, Ku-, and Ka-band. The designs are realized in 0.25 μm and 0.15 μm AlGaN/GaN microstrip technology.(More)