Microscale Magnetic Components for DC-DC Converter Applications

Core materials for microinductors and microtransformers were assessed for operation in the MHz frequency range. The performance of electrodeposited nickel-iron, cobalt-iron- copper alloys and the commercial alloy Vitrovac 6025 have been examined through their inclusion within a custom-made solenoid microinductor. Inductance values ranging from 0.3 muH to 120 muH with component power efficiency above 90% have been measured. Although the present inductor, at 500 KHz, achieves 91% power efficiency for 2.4 W/cm³ power density, an optimized component achieved a power efficiency of 94% for 28 W/cm³ power density.