Resistors and terminations

Updated July 4, 2011

Click here to go to our main page on lumped elements

Click here to go to our main page on skin depth

If you can't understand why these resistors might not work so well at 40 GHz, perhaps it's time to choose a new career... BTW, we get spammed with photos of stuff like this all the time, someone in China must think that Microwaves101 is in the business of masnufacturing obsolete consumer electronics...

So far we have four pages on the topics or reistors and terminations, but we've only scratched the surface!

Here is a clickable index to our material on resistors:

Resistors for microwave frequencies (this page)

Thick film resistors (separate page)

Thick-film fabrication process

Thick-fim chip resistors

Power rating

Thin film resistors (separate page)

Temperature stabilization

Trimming and tolerancing (separate page)

Waveguide terminations (coming soon)

Resistor mathematics (separate page)

Ohm's law

Sheet resistance

Resistor derating

Resistance temperature coefficient

Mesa resistors (separate page, new for April 2008)

Resistors for microwave frequencies

What's so special about microwave resistors? Axial-leaded resistors, the ones with the color-coded rings that you might be familiar with from misspent youth of busting stuff to "see how it works", are not going to work at microwave frequencies. This is because you have to consider that anything with dimensions longer than perhaps a sixteenth wavelength acts as distributed element. It is desirable for a resistor to behave like a lumped element in most microwave applications.

The problem that resistors have at microwave frequencies is that in order to be considered a lumped element, they must be physically small, but they must also be sized in order to dissipate power.