Hello,

In dealing with the distinction between discrete components and embedded
passive components, we have a simple concept. If you can separate the
component from the supporting substrate and hold it in the palm of your
hand, then it's a discrete component. However, if it's intergal to the
substrate (can not be separated), then it's a planar surface or embedded
component. Examples of the latter are resistors created by gaps in
resistive-conductive traces or capacitors created by overlapping
parallel conductors (one layer to another with a dielectric in between).

Ultimately, the question will become what's the difference between real
and virtual components that add neither size nor weight to the substrate
but work just a well as the real components in performing the same
functions. It sounds like science fiction but some HDI designs have
embedded passives that come close to meeting the "no size nor weight"
definition of a virtual component.

Dan Brandler
Ohmega Technologies

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