Experimental evaluation of large-signal modeling assumptions based on vector analysis of bias-dependent S-parameter data from MESFETs and HEMTs

Abstract

This paper presents, for the first time, a systematic experimental examination of the validity of basic largesignal modeling assumptions by subjecting measured Sparameter data versus bias from MESFETs and HEMTs to various mathematical operations of vector analysis. Several approaches are used to determine the degree to which pairs of device nonlinearities can be accurately modeled by charge-based nonlinear capacitors, voltage-controlled current sources, and higher-order elements arranged in a standard equivalent circuit topology. Implications are discussed for such circuit modeling concepts as terminal charge conservation and its extension to other statefunctions.

Development of extraction and optimization based large-signal models for thinned metamorphic high-electron mobility transistors on germanium

“…The modeling inaccuracies are on the same order of magnitude and one model is not consistently better than the other. The noticed modeling inaccuracies seem to largely originate from known limitations of equivalent circuit based nonlinear models [13], and they cannot be directly related to a possible physical phenomenon occurring in the thinned Ge based mHEMT that has not been taken into account. Therefore, we can conclude that thinned Ge mHEMTs can be modeled by techniques that are valid for "regular" HEMTs, as long as the maximal allowable heat dissipation is not exceeded.…”

An accurate and simplified small signal parameter extraction method for GaN HEMT

“…The AlGaN/GaN high electron mobility transistors (HEMTs) find applications in numerous domains including the design of high power and high efficiency RF power amplifiers (RFPAs) owing to its wide bandgap property. The wide bandgap allows the GaN devices to operate at higher power levels, whereas the high electron mobility makes it suitable for operation at higher speed and higher efficiency . The use of GaN devices in the design of RFPAs is still limited due to unavailability of its generic large signal models.…”

“…The wide bandgap allows the GaN devices to operate at higher power levels, whereas the high electron mobility makes it suitable for operation at higher speed and higher efficiency. [1][2][3][4][5][6] The use of GaN devices in the design of RFPAs is still limited due to unavailability of its generic large signal models. Instead, it is usual to develop appropriate small signal and large signal models for these devices before its utilization in the eventual design.…”

A spline large-signal FET model based on bias-dependent pulsed I-V measurement

“…An alternative approach is a table-based model, which stores extracted model parameters at many bias points directly in a table. Table-based models have demonstrated their abilities to accurately predict device performances, and these models are technology independent [1]- [4]. They also eliminate the need of optimization in the model-extraction process.…”