Fully embedded LC diplexer passive circuit into an organic package substrate

In this article, fully embedded and miniaturized diplexer passive circuit device has been developed and characterized for dual‐band/mode CDMA handset applications. The size of the embedded diplexer is significantly reduced by embedding high Q circular spiral inductors and high DK MIM capacitors into a low cost organic package substrate. The embedded inductor and capacitor have quality factors of 61 and 32 at 1 GHz. The fabricated diplexer has insertion losses and isolations of −0.5 and −23 dB at 824–894 MHz and −0.7 and −22 dB at 1850–1990 MHz, respectively. Its size is 3.9 mm × 3.9 mm × 0.77 mm (height). The fabricated diplexer is the smallest one which is fully embedded into a low cost organic package substrate. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2960–2963, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22921