Depletion-Mode GaN HEMT Q-Spoil Switches for MRI Coils IEEE TRANSACTIONS ON MEDICAL IMAGING Lu, J. Y., Grafendorfer, T., Zhang, T., Vasanawala, S., Robb, F., Pauly, J. M., Scott, G. C. 2016; 35 (12): 2558-2567

Abstract

Q-spoiling is the process of decoupling an MRI receive coil to protect the equipment and patient. Conventionally, Q-spoiling is performed using a PIN diode switch that draws significant current. In this work, a Q-spoiling technique using a depletion-mode Gallium Nitride HEMT device was developed for coil detuning at both 1.5 T and 3 T MRI. The circuits with conventional PIN diode Q-spoiling and the GaN HEMT device were implemented on surface coils. SNR was measured and compared for all surfaces coils. At both 1.5 T and 3 T, comparable SNR was achieved for all coils with the proposed technique and conventional Q-spoiling. The GaN HEMT device has significantly reduced the required power for Q-spoiling. The GaN HEMT device also provides useful safety features by detuning the coil when unpowered.

View details for DOI 10.1109/TMI.2016.2586053

View details for Web of Science ID 000391547700005

View details for PubMedID 27362895