No abstract

The inductance of low temperature processable particulate filled polymer matrix composite inductors is constrained by the limited magnetic properties of the polymer matrix. The microstructural and electrical properties of inductors made from amorphous nickel-zinc-iron oxide matrix filled with polycrystalline Nickel Zinc Ferrite (NZF) fillers are investigated in this study. NZF has high resistance, and is essential for high Pequency application to reduce eddy current loss. Planar spiral NZF-composite (with 20v% fillers) inductors were fabricated on glass wafer substrate and heated treated at different temperatures. The electrical properties of the inductors were characterized at frequencies in the MHz range. The inductance is found to increase between 10% -20% for composite inductor afrer heated at 300°C for 1 hour. The increase is comparable to those reported previously for polymer fem'te composite inductors, albeit the polymer version has signijicantly higher filler content (90wt%) while the current NZFcomposite filler content is markedly less (IO-20%). This indicates that the increase is associatedwith improvement of the matrix's properties. The changes in matrix microstructures were characterized by X-ray diffraction. The increase in inductance and associated electrical properties are then explained based on the observed microstructural changes. The increase in matrix inductance indicates that the current approach has strong potential in giving a large enhancement in inductance when high jiller content is used.

The design of a two dimensional (2D) quadrantally symmetric FIR filter with peak constrained magnitude response is considered. We further considered the design specification without explicitly specifying the transition band. A novel iterative algorithm without transition band specification is proposed to design FIR filters with various design constraints. The eigenfilter formulation further allows the proposed algorithm to incorporate time domain constraints simultaneously. Various design examples are presented to illustrate the versatility of the proposed 2D filter design method. Although we have not proven the convergence of the proposed algorithm, it is found to converge efficiently in all the simulations.

No abstract

No abstract