Hitachi Metals has developed a range of antennas made from a novel amorphous material that offers a true alternative to ferrite
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The new amorphous material, ACO-5, has high saturation magnetic flux density, very low hysteresis loss and low eddy current loss. In addition, its stability over temperature, shock resistance and smaller size are superior to ferrite alternatives. The ACO-5 material characteristics include a flux density of 0.60T, a coercive force of 0.32A/m, a rectangular ratio of 0.85, a core loss of 460kW/m3 and a Curie temperature of 210C.

Hitachiïs amorphous antennas are now available and are an excellent choice for applications in RFID and radio wristwatches.

Standard antennas measure either 4 x 20 x 4, 3 x 20 x 4.5 or 4 x 16 x 2.5mm.

Customised antennas are available in different shapes to work at frequencies of 40, 60, 77.5 or 134kHz.