Parasitics

New for February 2017

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Scabies are parasites.  Here's one up close and personal.

What are parasitics?  Parasitic elements, also called "parasitics" are the difference between ideal passive components, and real-life hardware. Lumped elements such as capacitors and inductors all have parasitic elements associated with them.  Why do we call them "parasitics" instead of "parasites?"  It's almost the same word, but "parasites" is associated with creepy-crawly things like that sarcoptes scabiei n the video above.

Capacitors have parasitic series inductance and resistance. The inductor/capacitor combination causes a self-resonance that manufacturers often specify. Here's a discussion of the effects of equivalent series resistance (ESR) of capacitors.

Inductors have parasitic series resistance and parallel capacitance.  The inductor/capacitor combination causes a self-resonance that manufacturers often specify.

Resistors have parasitic series inductance, and capacitance to ground, so they behave like lossy transmission lines. Typically, you want a resistor to have no more than 1/16 of a wavelength in phase length.

Transmission lines have parasitic losses which reduce their quality factor.

 

 

Author : Unknown Editor