Design and Fabrication of Low-Power, High-Frequency, High-Performance Magnetic Thin Film Transformer

저전력, 고주파, 고효율 자성박막 변압기 설계 및 제작에 대한 연구

  • 윤의중 (호서대 공대 전기공학부) ;
  • 정명희 (안양대 공대 디지털미디어학부)
  • Published : 2001.11.01

Abstract

In this paper, the low power (1.5 W) solenoid-type magnetic thin-film transformers utilizing a $Ni_{81}Fe_{19)$ core material were designed and fabricated for 5 MHz-drive DC-DC converter application. The $20\mum$ thick copper films were used as the coils. The transformers fabricated in this work have the sizes of $3.08 mm\times25.5 mm\; and\; 6.15 mm\times12.75 mm.$ The optimum design of solenoid-type magnetic thin film transformers was performed utilizing the conventional equations, a Maxwell computer simulator (Ansoft HFSS V7.0 for PC), and parameters obtained from the magnetic properties of NiFe magnetic core materials. frequency characteristics of inductance, dc resistance (R), coupling factor (k) and gain of developed transformers were measured using HP4194A impedance and gain-phase analyzer. The fabricated transformers with the size of $6.15 mm\time12.75 mm$ exhibit the inductance of $0.83 \muH$, the dc resistance of $2.3\Omega$$\Omega$, the k of 0.91 and the gain of -1 dB at 5 MHz, which show the comparable results to those reported in the recent literatures. The measured high-frequency characteristics for the fabricated transformers agreed well with those obtained by theoretical calculations .

Keywords

solenoid-type;thin-film transformers;DC-DC converter;$Ni_{81}Fe_{19)$ core;Maxwell simulator;high-frequency

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