2007 IEEE Design and Diagnostics of Electronic Circuits and Systems (2007)
Apr. 11, 2007 to Apr. 13, 2007
V. Dumbrava , Kaunas University of Technology, Department of Signal Processing, Studentu str. 50-340, LT-51368, Kaunas, Lithuania
L. Svilainis , Kaunas University of Technology, Department of Signal Processing, Studentu str. 50-340, LT-51368, Kaunas, Lithuania. email@example.com
The analysis and the measurement technique of the RF transformer model is presented. Transformer is used to improve the SNR of the input stages and for DC biasing through the winding inductance. The frequency range 0.1 MHz to 10 MHz utilized by the conventional ultrasound is assumed. Model is incorporating the winding resistances and the core loss resistance. The winding resistances experimental measurements and the modelling results comparison are presented. It has been indicated that winding resistances variance of ?20 % is causing only 0.02 dB variation in the preamplifier noise figure if source impedance is low. The core loss resistance measurement and experimental investigation results are outlined. It is shown that ?20% variance of this resistance can cause preamplifier noise figure variations reaching 0.03 dB for high output impedance transducer.
V. Dumbrava and L. Svilainis, "RF Transformer Model Parameters Measurement," 2007 IEEE Design and Diagnostics of Electronic Circuits and Systems(DDECS), Krakow, Poland, 2007, pp. 1-5.