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Abstract #0725

Enhancement Mode GaN (EGaN) FETs for On-Coil MRI Transmit Amplifiers

Michael Twieg1, Matthew J. Riffe2, Natalia Gudino2, Mark A. Griswold, 13

1Dept. of Electrical Engineering and Computer Science, Case Western Reserve University, Cleveland, OH, United States; 2Dept. of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States; 3Dept. of Radiology, Case Western Reserve University, Cleveland, OH, United States

We present the first use of enhancement-mode Gallium Nitride (eGaN) FETs, a novel emerging transistor technology, in on-coil transmit amplifiers for MRI. This work demonstrates the operation of a complete miniature on-coil amplifier module using the current mode class D (CMCD) topology as well as AM modulation via envelope elimination and restoration (EER). We show that the small size and low cost of eGaN FETs offer significant advantages over traditional Silicon (Si) FET technology for small and high efficiency RF amplifiers.

Keywords

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