Engineering Commons^™

A High Gain Multi-Stage Operational Amplifier Using Compound Transconductance Element, Chandra Sekhar Acharyulu Durisety

Doctoral Dissertations

The rapid increase in integrated circuit complexity attributed to the advancements in fabrication techniques combined with the increasing demand for consumer applications has created an immense demand for high performance analog systems. These analog systems include high-resolution (≥ 14-bit) and/or high-speed (≥ 1 GHz) ADCs, high- linearity filters and power management circuits. The fundamental limitations in these systems are tied to the constraints imposed by the basic design elements that tend to include amplifiers and reference generators (voltage/current). With continued technology scaling, innovative circuits and design techniques are necessary in achieving high performance analog/mixed-signal systems.

The goal of this research …

Temperature Dependent Analytical Modeling, Simulation And Characterizations Of Hemts In Gallium Nitride Process, Hasina F. Huq

Doctoral Dissertations

Research is being conducted for a high-performance building block for high frequency and high temperature applications that combine lower costs with improved performance and manufacturability. Researchers have focused their attention on new semiconductor materials for use in device technology to address system improvements. Of the contenders, silicon carbide (SiC), gallium nitride (GaN), and diamond are emerging as the front-runners.

GaN-based electronic devices, AlGaN/GaN heterojunction field effect transistors (HFETs), are the leading candidates for achieving ultra-high frequency and high-power amplifiers. Recent advances in device and amplifier performance support this claim. GaN is comparable to the other prominent material options for high-performance …

A Generalized Instantaneous Nonactive Power Theory For Parallel Nonactive Power Compensation, Yan Xu

Doctoral Dissertations

Although the definitions of active power and nonactive power in a three-phase sinusoidal power system have been accepted as a standard, it has been an issue on how to define instantaneous nonactive power in power systems with non-sinusoidal or even non- periodic voltage and/or current.

This dissertation summarizes these nonactive power theories, and a generalized instantaneous nonactive power theory is presented. By changing the parameters in the instantaneous active current and nonactive current definitions, this theory is valid for power systems with different characteristics. Furthermore, other nonactive power theories can be derived from this generalized theory by changing parameters.

This …